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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
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package javax.faces.component;


import java.io.IOException;
import java.io.InputStream;

import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import java.util.MissingResourceException;
import java.util.PropertyResourceBundle;
import java.util.ResourceBundle;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.el.ELContext;
import javax.el.ELException;
import javax.el.ValueExpression;
import javax.faces.FacesException;
import javax.faces.FacesWrapper;
import javax.faces.application.Resource;
import javax.faces.component.visit.VisitCallback;
import javax.faces.component.visit.VisitContext;
import javax.faces.component.visit.VisitHint;
import javax.faces.component.visit.VisitResult;
import javax.faces.context.FacesContext;
import javax.faces.el.ValueBinding;
import javax.faces.event.AbortProcessingException;
import javax.faces.event.PostRestoreStateEvent;
import javax.faces.event.ComponentSystemEvent;
import javax.faces.event.ComponentSystemEventListener;
import javax.faces.event.FacesEvent;
import javax.faces.event.SystemEvent;
import javax.faces.event.SystemEventListener;
import javax.faces.event.FacesListener;
import javax.faces.event.SystemEventListenerHolder;
import javax.faces.render.Renderer;

/**
 * 
UIComponent is
 * the base class for all user interface components in JavaServer Faces.
 * The set of {@link UIComponent} instances associated with a particular request
 * and response are organized into a component tree under a {@link
 * UIViewRoot} that represents the entire content of the request or
 * response.

 *
 * 
For the convenience of component developers,
 * {@link UIComponentBase} provides the default
 * behavior that is specified for a {@link UIComponent}, and is the base class
 * for all of the concrete {@link UIComponent} "base" implementations.
 * Component writers are encouraged to subclass
 * {@link UIComponentBase}, instead of directly
 * implementing this abstract class, to reduce the impact of any future changes
 * to the method signatures.

 *
 * 
If the {@link
 * javax.faces.event.ListenerFor} annotation is attached to the class
 * definition of a Component, that class must also
 * implement {@link javax.faces.event.ComponentSystemEventListener}.
 * 


 */

public abstract class UIComponent implements PartialStateHolder, TransientStateHolder, SystemEventListenerHolder,
        ComponentSystemEventListener {

    private static Logger LOGGER = Logger.getLogger("javax.faces.component",
            "javax.faces.LogStrings");

    /**
     * 
The ServletContext init
     * parameter consulted by
     * the UIComponent to tell whether or not the
     * {@link #CURRENT_COMPONENT} and {@link #CURRENT_COMPOSITE_COMPONENT}
     * attribute keys should be honored as specified.

     *
     * 
If this parameter is not specified, or is set to false, the contract
     * specified by the {@link #CURRENT_COMPONENT} and
     * {@link #CURRENT_COMPOSITE_COMPONENT} method is not honored. If this
     * parameter is set to true, the contract is honored.

     */
    public static final String HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME =
            "javax.faces.HONOR_CURRENT_COMPONENT_ATTRIBUTES";
    
    /**
     * 
The key to which the
     * UIComponent currently being processed will be
     * associated with within the {@link FacesContext} attributes
     * map. The use of this constant is
     * deprecated.  Please see {@link
     * #HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME} to enable its
     * use.

     *
     * @see javax.faces.context.FacesContext#getAttributes()
     *
     * @since 2.0
     *
     * @deprecated
     */
    public static final String CURRENT_COMPONENT = "javax.faces.component.CURRENT_COMPONENT";

    /**
     * 
The key to which the
     * composite UIComponent currently being
     * processed will be associated with within the {@link FacesContext}
     * attributes map. The use of this
     * constant is deprecated.  Please see {@link
     * #HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME} to enable its
     * use.

     *
     * @see javax.faces.context.FacesContext#getAttributes()
     *
     * @since 2.0
     *
     * @deprecated
     */
    public static final String CURRENT_COMPOSITE_COMPONENT = "javax.faces.component.CURRENT_COMPOSITE_COMPONENT";

    /**
     * 
The value of this constant is used as the key in the
     * component attribute map, the value for which is a
     * java.beans.BeanInfo implementation describing the composite
     * component.  This BeanInfo is known as the 
     * composite component BeanInfo.

     *
     * @since 2.0
     */
    public static final String BEANINFO_KEY = "javax.faces.component.BEANINFO_KEY";


    /**
     * 
The value of this constant is used as the key
     * in the composite component BeanDescriptor for the 
     * Map<PropertyDescriptor> that contains meta-information
     * for the declared facets for this composite component.
     * This map must contain an entry under the key {@link #COMPOSITE_FACET_NAME}, even
     * if no facets were explicitly declared.  See {@link #COMPOSITE_FACET_NAME}.

     *
     * @since 2.0
     */
    public static final String FACETS_KEY = "javax.faces.component.FACETS_KEY";
    
    /**
     * 
The value of this constant is used as the key
     * in the component attributes Map for the 
     * {@link javax.faces.view.Location} in the view at which this component 
     * instance resides.

     *
     * @since 2.0
     */
    public static final String VIEW_LOCATION_KEY = "javax.faces.component.VIEW_LOCATION_KEY";
    
    /**
     * 
The value of this constant is used as the key
     * in the composite component BeanDescriptor for a 
     * ValueExpression that evaluates to the 
     * component-type of the composite component root
     * UIComponent for this composite component, if
     * one was declared by the composite component author.

     *
     * @since 2.0
     */
    public static final String COMPOSITE_COMPONENT_TYPE_KEY = "javax.faces.component.COMPOSITE_COMPONENT_TYPE";
    
    /**
     * 
The value of this constant is used as the key
     * in the Map returned as described in {@link #FACETS_KEY}
     * for the 
     * PropertyDescriptor describing the composite component facet.
     * The value of this constant is also used as the key in the Map
     * returned from {@link #getFacets}.  In this case, it refers to the actual
     * facet that is the {@link javax.faces.component.UIPanel} that is the parent of the all
     * of the components in the <composite:implementation>
     * section of the composite component VDL file.

     *
     * @since 2.0
     */
    public static final String COMPOSITE_FACET_NAME = "javax.faces.component.COMPOSITE_FACET_NAME";

    /**
     * 
This constant enables one to quickly discover
     * the names of the declared composite component attributes that have been
     * given default values by the composite component author.  The information
     * is exposed as a Collection<String> returned from the
     * getValue() method on the composite component
     * BeanDescriptor, when this constant is passed as the argument.

     *
     * @since 2.1
     */
    public static final String ATTRS_WITH_DECLARED_DEFAULT_VALUES =
            "javax.faces.component.ATTR_NAMES_WITH_DEFAULT_VALUES";

    enum PropertyKeysPrivate {
        attributesThatAreSet
    }

    /**
     * Properties that are tracked by state saving.
     */
    enum PropertyKeys {
        rendered,
        attributes,
        bindings,
        rendererType,
        systemEventListeners,
        behaviors,
        passThroughAttributes
    }

    /**
     * List of attributes that have been set on the component (this
     * may be from setValueExpression, the attributes map, or setters
     * from the concrete HTML components.  This allows
     * for faster rendering of attributes as this list is authoritative
     * on what has been set.
     */
    List attributesThatAreSet;
    ComponentStateHelper stateHelper = null;
    UIComponent compositeParent;


    // -------------------------------------------------------------- Attributes


    /**
     * 
Return a mutable 
     * Map representing the attributes
     * (and properties, see below) associated wth this {@link UIComponent},
     * keyed by attribute name (which must be a String).  The returned
     * implementation must support all of the standard and optional
     * Map methods, plus support the following additional
     * requirements:

     * 
    
     * 
  • The Map implementation must implement
     *     the java.io.Serializable interface.
    • 
     * 
  • Any attempt to add a null key or value must
     *     throw a NullPointerException.
    • 
     * 
  • Any attempt to add a key that is not a String must throw
     *     a ClassCastException.
    • 
     * 
  • If the attribute name specified as a key matches a property
     *     of this {@link UIComponent}'s implementation class, the following
     *     methods will have special behavior:
     *     
      
     *     
    • containsKey - Return false.
      • 
     *     
    • get() - If the property is readable, call
     *         the getter method and return the returned value (wrapping
     *         primitive values in their corresponding wrapper classes);
     *         otherwise throw IllegalArgumentException.
      • 
     *     
    • put() - If the property is writeable, call
     *         the setter method to set the corresponding value (unwrapping
     *         primitive values in their corresponding wrapper classes).
     *         If the property is not writeable, or an attempt is made to
     *         set a property of primitive type to null,
     *         throw IllegalArgumentException.
      • 
     *     
    • remove - Throw
     *         IllegalArgumentException.
      • 
     *     
    • 
     * 

     * 
     */
    public abstract Map getAttributes();
    
    /**
     * 
This is a convenience method that 
     * simply calls {@link #getPassThroughAttributes(boolean)}, passing {@code true}
     * as the argument.  This method must never return {@code null}.

     * 
     * @since 2.2
     */

    public final Map getPassThroughAttributes(){
        
        return getPassThroughAttributes(true);
    }
    
    
    /**
     * 
This method has the same specification as 
     * {@link #getPassThroughAttributes() } except that it is allowed to return 
     * {@code null} if and only if the argument {@code create} is {@code false}
     * and no pass through attribute data structure exists for this instance.  
     * The returned {@code Map} implementation must support all of the standard and optional 
     * {@code Map} methods, plus support the following additional requirements.
     * The map must be stored in using {@link #getStateHelper}.

     * 
     * 

     * 
     * 
The {@code Map} implementation must implement {@code java.io.Serializable}.

     * 
     * 
Any attempt to add a {@code null} key or value must throw a {@code NullPointerException}.

     * 
     * 
Any attempt to add a key that is not a {@code String} must
     * throw an {@code IllegalArgumentException}.

     * 
     * 
For backward compatibility with components that extend directly from
     * this class, a default implementation is provided that returns the empty
     * map.

     * 
     * 

     *
     * @param create if true, a new {@code Map}
     * instance will be created if it does not exist already.  If
     * false, and there is no existing
     * Map instance, one will not be created and
     * null will be returned.
     * @return A {@code Map} instance, or {@code null}.
     * 
     * @since 2.2
     */
    
    public Map getPassThroughAttributes(boolean create) {
        return Collections.emptyMap();
    }
    
    // ---------------------------------------------------------------- Bindings


    /**
     *
     * 
Call through to {@link #getValueExpression} and examine the
     * result.  If the result is an instance of the wrapper class
     * mandated in {@link #setValueBinding}, extract the
     * ValueBinding instance and return it.  Otherwise,
     * wrap the result in an implementation of
     * ValueBinding, and return it.

     *
     * @param name Name of the attribute or property for which to retrieve a
     *  {@link ValueBinding}
     *
     * @throws NullPointerException if name
     *  is null
     *
     * @deprecated This has been replaced by {@link #getValueExpression}.
     */
    public abstract ValueBinding getValueBinding(String name);


    /**
     * 
Wrap the argument binding in an implementation of
     * {@link ValueExpression} and call through to {@link
     * #setValueExpression}.

     *
     * @param name Name of the attribute or property for which to set a
     *  {@link ValueBinding}
     * @param binding The {@link ValueBinding} to set, or null
     *  to remove any currently set {@link ValueBinding}
     *
     * @throws IllegalArgumentException if name is one of
     *  id or parent
     * @throws NullPointerException if name
     *  is null
     *
     * @deprecated This has been replaced by {@link #setValueExpression}.
     */
    public abstract void setValueBinding(String name, ValueBinding binding);

    // The set of ValueExpressions for this component, keyed by property
    // name This collection is lazily instantiated
    // The set of ValueExpressions for this component, keyed by property
    // name This collection is lazily instantiated
    @Deprecated
    protected Map bindings = null;

    /**
     * 
Return the {@link ValueExpression} used to calculate the value for the
     * specified attribute or property name, if any.

     *
     * 
This method must be overridden and implemented for components that
     * comply with JSF 1.2 and later.

     *
     * @since 1.2
     *
     * @param name Name of the attribute or property for which to retrieve a
     *  {@link ValueExpression}
     *
     * @throws NullPointerException if name
     *  is null
     *
     */
    public ValueExpression getValueExpression(String name) {

        if (name == null) {
            throw new NullPointerException();
        }

        Map map = (Map)
              getStateHelper().get(UIComponentBase.PropertyKeys.bindings);
        return ((map != null) ? map.get(name) : null);

    }

    /**
     * 
Set the {@link ValueExpression} used to calculate the value
     * for the specified attribute or property name, if any.

     *
     * 
The implementation must call {@link
     * ValueExpression#isLiteralText} on the argument
     * expression.  If isLiteralText() returns
     * true, invoke {@link ValueExpression#getValue} on the
     * argument expression and pass the result as the value
     * parameter in a call to this.{@link
     * #getAttributes()}.put(name, value) where name
     * is the argument name.  If an exception is thrown as
     * a result of calling {@link ValueExpression#getValue}, wrap it in
     * a {@link javax.faces.FacesException} and re-throw it.  If
     * isLiteralText() returns false, simply
     * store the un-evaluated expression argument in the
     * collection of ValueExpressions under the key given
     * by the argument name.

     *
     * 
This method must be overridden and implemented for components that
     * comply with JSF 1.2 and later.

     *
     * @since 1.2
     *
     * @param name Name of the attribute or property for which to set a
     *  {@link ValueExpression}
     * @param binding The {@link ValueExpression} to set, or null
     *  to remove any currently set {@link ValueExpression}
     *
     * @throws IllegalArgumentException if name is one of
     *  id or parent
     * @throws NullPointerException if name
     *  is null
     *
     */
    public void setValueExpression(String name, ValueExpression binding) {

        if (name == null) {
            throw new NullPointerException();
        } else if ("id".equals(name) || "parent".equals(name)) {
            throw new IllegalArgumentException();
        }

        if (binding != null) {
            if (!binding.isLiteralText()) {
                //if (bindings == null) {
                //    //noinspection CollectionWithoutInitialCapacity
                //    bindings = new HashMap();
                //}
                // add this binding name to the 'attributesThatAreSet' list
                //List sProperties = (List)
                //      getStateHelper().get(PropertyKeysPrivate.attributesThatAreSet);

                 List sProperties =
                      (List) getStateHelper().get(PropertyKeysPrivate.attributesThatAreSet);
                if (sProperties == null) {
                    getStateHelper().add(PropertyKeysPrivate.attributesThatAreSet, name);
                } else if (!sProperties.contains(name)) {
                    getStateHelper().add(PropertyKeysPrivate.attributesThatAreSet, name);
                }
                getStateHelper().put(UIComponentBase.PropertyKeys.bindings,
                                     name,
                                     binding);
                //bindings.put(name, binding);
            } else {
                ELContext context =
                    FacesContext.getCurrentInstance().getELContext();
                try {
                    getAttributes().put(name, binding.getValue(context));
                } catch (ELException ele) {
                    throw new FacesException(ele);
                }
            }
        } else {
            //if (bindings != null) {
                // remove this binding name from the 'attributesThatAreSet' list
//                List sProperties = getAttributesThatAreSet(false);
//                if (sProperties != null) {
//                    sProperties.remove(name);
//                }
                getStateHelper().remove(PropertyKeysPrivate.attributesThatAreSet,
                                        name);
                getStateHelper().remove(UIComponentBase.PropertyKeys.bindings, name);
                //bindings.remove(name);
               // if (bindings.isEmpty()) {
               //     bindings = null;
               // }
            }
       // }

    }

    // -------------------------------------------------------------- Properties

    boolean initialState;

    /**
     * 
An implementation of {@link
     * PartialStateHolder#markInitialState}, this method is called by
     * the runtime to indicate that the instance should start tracking
     * changes to its state.

     * @since 2.0
     */
    public void markInitialState() {
        initialState = true;
    }


    /**
     * 
An implementation of {@link
     * PartialStateHolder#initialStateMarked}, this method is called by
     * the runtime to test if the {@link
     * PartialStateHolder#markInitialState} method was called.

     * @since 2.0
     */
    public boolean initialStateMarked() {
        return initialState;
    }


    /**
     * 
An implementation of {@link
     * PartialStateHolder#clearInitialState}, this method is called by
     * the runtime to tell the instance to stop tracking state
     * changes.

     * @since 2.0
     */
    public void clearInitialState() {
        initialState = false;
    }


    /**
     * 
Return the {@link StateHelper}
     * instance used to help this component implement {@link
     * PartialStateHolder}.

     * @since 2.0
     */
    protected StateHelper getStateHelper() {
        return getStateHelper(true);
    }


    /**
     * 
Like {@link #getStateHelper()}, but
     * only create a state helper instance if the argument
     * creat is true.

     * @param create if true, a new {@link StateHelper}
     * instance will be created if it does not exist already.  If
     * false, and there is no existing
     * StateHelper instance, one will not be created and
     * null will be returned.
     * @since 2.0
     */
    protected StateHelper getStateHelper(boolean create) {

        if (create && stateHelper == null) {
            stateHelper = new ComponentStateHelper(this);
        }
        return stateHelper;

    }

    /**
     * 
Return the {@link
     * TransientStateHelper} instance for this UIComponent
     * instance.  The default implementation simply calls through to
     * {@link #getTransientStateHelper(boolean)} passing true
     * as the argument.

     *
     * @since 2.1
     */
    
    public final TransientStateHelper getTransientStateHelper()
    {
        return getTransientStateHelper(true);
    }
    
    /**
     * 
Return the {@link
     * TransientStateHelper} instance for this UIComponent
     * instance.

     *
     * @param create if true create, if necessary, any
     * internal data structures.  If false, do not create
     * any instances.  In this case, it is possible for this method to
     * return null.
     *
     * @since 2.1
     */
    
    public TransientStateHelper getTransientStateHelper(boolean create) {
        
        if (create && stateHelper == null) {
            stateHelper = new ComponentStateHelper(this);
        }
        return stateHelper;
        
    }

    /**
     * 
For components that need to support
     * the concept of transient state, this method will restore any
     * state saved on a prior call to {@link #saveTransientState}.

     *
     * @since 2.1
     */
    
    public void restoreTransientState(FacesContext context, Object state)
    {
        boolean forceCreate = (state != null);
        TransientStateHelper helper = getTransientStateHelper(forceCreate);

        if (helper != null) {
            helper.restoreTransientState(context, state);
        }
    }

    /**
     * 
For components that need to support
     * the concept of transient state, this method will save any state
     * that is known to be transient in nature.

     *
     * @since 2.1
     */
    
    public Object saveTransientState(FacesContext context)
    {
        TransientStateHelper helper = getTransientStateHelper(false);

        return (helper == null) ? null : helper.saveTransientState(context);
    }

    private boolean isInView;


    /**
     * 
Return true if this
     * component is within the view hierarchy otherwise
     * false
     *
     * @since 2.0
     */
    public boolean isInView() {
        return isInView;
    }


    /**
     * 
Updates the status as to whether or
     * not this component is currently within the view hierarchy.
     * This method must never be called by developers; a {@link
     * UIComponent}'s internal implementation will call it as components
     * are added to or removed from a parent's child List
     * or facet Map.

     *
     * @param isInView flag indicating whether or not this component is within
     *  the view hierachy
     *
     * @since 2.0
     */
    public void setInView(boolean isInView) {
        this.isInView = isInView;
    }


    /**
     * 
Enable EL to access the clientId
     * of a component.  This is particularly useful in combination with the 
     * component and cc implicit
     * objects.  A default implementation is provided that simply calls
     * {@link FacesContext#getCurrentInstance} and then calls through to
     * {@link #getClientId(FacesContext)}.

     * 
     * @since 2.0
     */
    
    public String getClientId() {
        FacesContext context = FacesContext.getCurrentInstance();
        return getClientId(context);
    }


    /**
     * 
Return a client-side identifier for this component, generating
     * one if necessary.  The associated {@link Renderer}, if any,
     * will be asked to convert the clientId to a form suitable for
     * transmission to the client.

     *
     * 
The return from this method must be the same value throughout
     * the lifetime of the instance, unless the id property
     * of the component is changed, or the component is placed in
     * a {@link NamingContainer} whose client ID changes (for example,
     * {@link UIData}).  However, even in these cases, consecutive
     * calls to this method must always return the same value.  The
     * implementation must follow these steps in determining the
     * clientId:

     *
     * 
Find the closest ancestor to this component in the view
     * hierarchy that implements NamingContainer.  Call
     * getContainerClientId() on it and save the result as
     * the parentId local variable.  Call {@link #getId} on
     * this component and save the result as the
     * myId local variable.  If myId is
     * null, call
     * context.getViewRoot().createUniqueId() and assign
     * the result to myId.  If parentId is
     * non-null, let myId equal parentId
     * + {@link UINamingContainer#getSeparatorChar} + myId.  Call
     * {@link Renderer#convertClientId}, passing myId, and
     * return the result.

     *
     * @param context The {@link FacesContext} for the current request
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract String getClientId(FacesContext context);

    /**
     * 
Allow components that implement {@link NamingContainer} to
     * selectively disable prepending their clientId to their
     * descendent's clientIds by breaking the prepending logic into a
     * seperately callable method.  See {@link #getClientId} for usage.

     *
     * 
By default, this method will call through to {@link
     * #getClientId} and return the result.
     *
     * @since 1.2
     *
     *  @throws NullPointerException if context is
     *  null
     */
    public String getContainerClientId(FacesContext context) {
        if (context == null) {
            throw new NullPointerException();
        }
        return this.getClientId(context);
    }

    /**
     * 
Return the identifier of the component family to which this
     * component belongs.  This identifier, in conjunction with the value
     * of the rendererType property, may be used to select
     * the appropriate {@link Renderer} for this component instance.

     */
    public abstract String getFamily();


    /**
     * 
Return the component identifier of this {@link UIComponent}.

     */
    public abstract String getId();


    /**
     * 
Set the component identifier of this {@link UIComponent} (if any).
     * Component identifiers must obey the following syntax restrictions:

     * 
    
     * 
  • Must not be a zero-length String.
    • 
     * 
  • First character must be a letter or an underscore ('_').
    • 
     * 
  • Subsequent characters must be a letter, a digit,
     *     an underscore ('_'), or a dash ('-').
    • 
     * 
  • 
     * 

     *
     * 
Component identifiers must also obey the following semantic
     * restrictions (note that this restriction is NOT
     * enforced by the setId() implementation):

     * 
    
     * 
  • The specified identifier must be unique among all the components
     *     (including facets) that are descendents of the nearest ancestor
     *     {@link UIComponent} that is a {@link NamingContainer}, or within
     *     the scope of the entire component tree if there is no such
     *     ancestor that is a {@link NamingContainer}.
    • 
     * 

     *
     * @param id The new component identifier, or null to indicate
     *  that this {@link UIComponent} does not have a component identifier
     *
     * @throws IllegalArgumentException if id is not
     *  syntactically valid
     */
    public abstract void setId(String id);


    /**
     * 
Return the parent {@link UIComponent} of this
     * UIComponent, if any.  A component must allow child
     * components to be added to and removed from the list of children
     * of this component, even though the child component returns null
     * from getParent( ).

     */
    public abstract UIComponent getParent();


    /**
     * 
Set the parent
     * UIComponent of this UIComponent.  If
     * parent.isInView() returns true, calling
     * this method will first cause a {@link
     * javax.faces.event.PreRemoveFromViewEvent} to be published, for
     * this node, and then the children of this node.  Then, once the
     * re-parenting has occurred, a {@link
     * javax.faces.event.PostAddToViewEvent} will be published as well,
     * first for this node, and then for the node's children, but only if any of the
     * following conditions are true.


     * 


     *     
    

     *       
  • {@link
     *       javax.faces.context.FacesContext#getCurrentPhaseId} returns
     *       {@link javax.faces.event.PhaseId#RESTORE_VIEW} and partial
     *       state saving is enabled.
    • 

     *       
  • {@link javax.faces.context.FacesContext#isPostback}
     *       returns false and {@link
     *       javax.faces.context.FacesContext#getCurrentPhaseId} returns
     *       something other than {@link
     *       javax.faces.event.PhaseId#RESTORE_VIEW}
    • 

     *    


     * 



     * 
 This method must never
     * be called by developers; a {@link UIComponent}'s internal
     * implementation will call it as components are added to or removed
     * from a parent's child List or facet
     * Map.

     *
     * @param parent The new parent, or null for the root node
     *  of a component tree
     */
    public abstract void setParent(UIComponent parent);


    /**
     * 
Return true if this component (and its children)
     * should be rendered during the Render Response phase
     * of the request processing lifecycle.

     */
    public abstract boolean isRendered();


    /**
     * 
Set the rendered property of this
     * {@link UIComponent}.

     *
     * @param rendered If true render this component;
     *  otherwise, do not render this component
     */
    public abstract void setRendered(boolean rendered);


    /**
     * 
Return the {@link Renderer} type for this {@link UIComponent}
     * (if any).

     */
    public abstract String getRendererType();


    /**
     * 
Set the {@link Renderer} type for this {@link UIComponent},
     * or null for components that render themselves.

     *
     * @param rendererType Logical identifier of the type of
     *  {@link Renderer} to use, or null for components
     *  that render themselves
     */
    public abstract void setRendererType(String rendererType);


    /**
     * 
Return a flag indicating whether this component is responsible
     * for rendering its child components.  The default implementation
     * in {@link UIComponentBase#getRendersChildren} tries to find the
     * renderer for this component.  If it does, it calls {@link
     * Renderer#getRendersChildren} and returns the result.  If it
     * doesn't, it returns false.  As of version 1.2 of the JavaServer
     * Faces Specification, component authors are encouraged to return
     * true from this method and rely on {@link
     * UIComponentBase#encodeChildren}.

     */
    public abstract boolean getRendersChildren();
    

    
    private Map resourceBundleMap = null;
    
    /**
     * 
Return a
     * Map<String,String> of the
     * ResourceBundle for this component.  A component may
     * have a ResourceBundle associated with it.  This
     * bundle may contain localized properties relating to instances of
     * this component.  The default implementation first looks for a
     * ResourceBundle with a base name equal to the fully
     * qualified class name of the current UIComponent this
     * and Locale equal to the Locale of the
     * current UIViewRoot.  If no such bundle is found, and
     * the component is a composite component, let resourceName
     * be the resourceName of the {@link Resource} for this
     * composite component, replacing the file extension with
     * ".properties".  Let libraryName be the
     * libraryName of the the {@link Resource} for this
     * composite component.  Call {@link
     * javax.faces.application.ResourceHandler#createResource(java.lang.String,java.lang.String)},
     * passing the derived resourceName and
     * libraryName.  Note that this will automatically allow
     * for the localization of the ResourceBundle due to
     * the localization facility implemented in
     * createResource, which is specified in section
     * JSF.2.6.1.3 of the spec prose document.  If the resultant {@link
     * Resource} exists and can be found, the InputStream
     * for the resource is used to create a ResourceBundle.
     * If either of the two previous steps for obtaining the
     * ResourceBundle for this component is successful, the
     * ResourceBundle is wrapped in a
     * Map<String,String> and returned.  Otherwise
     * Collections.EMPTY_MAP is returned.

     *
     * @since 2.0
     */
    public Map getResourceBundleMap() {
        
        if (null == resourceBundleMap) {
            // See if there is a ResourceBundle under the FQCN for this class
            String className = this.getClass().getName();
            Locale currentLocale = null;
            FacesContext context = null;
            UIViewRoot root = null;
            ResourceBundle resourceBundle = null;
            
            // Step 1: look for a ResourceBundle under the FQCN of this instance
            if (null != (context = FacesContext.getCurrentInstance())) {
                if (null != (root = context.getViewRoot())) {
                    currentLocale = root.getLocale();
                }
            }
            if (null == currentLocale) {
                currentLocale = Locale.getDefault();
            }
            try {
                resourceBundle = 
                        ResourceBundle.getBundle(className, currentLocale);
            } catch (MissingResourceException e) {
                // It is not an error if there is no ResourceBundle
            }
            
            // Step 2: if this is a composite component, look for a 
            // ResourceBundle as a Resource
            if (null == resourceBundle) {
                if (this.getAttributes().containsKey(Resource.COMPONENT_RESOURCE_KEY)) {
                    Resource ccResource = (Resource)
                            this.getAttributes().get(Resource.COMPONENT_RESOURCE_KEY);
                    if (null != ccResource) {
                        if (null != (ccResource = 
                                findComponentResourceBundleLocaleMatch(context, 
                                ccResource.getResourceName(), 
                                ccResource.getLibraryName()))) {
                            InputStream propertiesInputStream = null;
                            try {
                                propertiesInputStream = ccResource.getInputStream();
                                resourceBundle = new PropertyResourceBundle(propertiesInputStream);
                            } catch (IOException ex) {
                                Logger.getLogger(UIComponent.class.getName()).log(Level.SEVERE, null, ex);
                            } finally{
                            	if(null != propertiesInputStream){
                                    try{
                                        propertiesInputStream.close();
                                    } catch(IOException ioe){
                                        if (LOGGER.isLoggable(Level.SEVERE)) {
                                            LOGGER.log(Level.SEVERE, null, ioe);
                                        }
                                    }
                            	}
                            }
                        }
                    }
                }
            }
            
            // Step 3: if the previous steps yielded a ResourceBundle, wrap it
            // with a Map
            
            if (null != resourceBundle) {
                final ResourceBundle bundle = resourceBundle;
                resourceBundleMap = 
                        new Map() {
                            // this is an immutable Map

                            public String toString() {
                                StringBuffer sb = new StringBuffer();
                                Iterator> entries =
                                        this.entrySet().iterator();
                                Map.Entry cur;
                                while (entries.hasNext()) {
                                    cur = entries.next();
                                    sb.append(cur.getKey()).append(": ").append(cur.getValue()).append('\n');
                                }

                                return sb.toString();
                            }

                            // Do not need to implement for immutable Map
                            public void clear() {
                                throw new UnsupportedOperationException();
                            }


                            public boolean containsKey(Object key) {
                                boolean result = false;
                                if (null != key) {
                                    result = (null != bundle.getObject(key.toString()));
                                }
                                return result;
                            }


                            public boolean containsValue(Object value) {
                                Enumeration keys = bundle.getKeys();
                                boolean result = false;
                                while (keys.hasMoreElements()) {
                                    Object curObj = bundle.getObject(keys.nextElement());
                                    if ((curObj == value) ||
                                            ((null != curObj) && curObj.equals(value))) {
                                        result = true;
                                        break;
                                    }
                                }
                                return result;
                            }


                            public Set> entrySet() {
                                HashMap mappings = new HashMap();
                                Enumeration keys = bundle.getKeys();
                                while (keys.hasMoreElements()) {
                                    String key = keys.nextElement();
                                    Object value = bundle.getObject(key);
                                    mappings.put(key, value);
                                }
                                return mappings.entrySet();
                            }


                            @Override
                            public boolean equals(Object obj) {
                                return !((obj == null) || !(obj instanceof Map))
                                         && entrySet().equals(((Map) obj).entrySet());

                            }


                            public Object get(Object key) {
                                if (null == key) {
                                    return null;
                                }
                                try {
                                    return bundle.getObject(key.toString());
                                } catch (MissingResourceException e) {
                                    return "???" + key + "???";
                                }
                            }


                            public int hashCode() {
                                return bundle.hashCode();
                            }


                            public boolean isEmpty() {
                                Enumeration keys = bundle.getKeys();
                                return !keys.hasMoreElements();
                            }


                            public Set keySet() {
                                Set keySet = new HashSet();
                                Enumeration keys = bundle.getKeys();
                                while (keys.hasMoreElements()) {
                                    keySet.add(keys.nextElement());
                                }
                                return keySet;
                            }


                            // Do not need to implement for immutable Map
                            public Object put(Object k, Object v) {
                                throw new UnsupportedOperationException();
                            }


                            // Do not need to implement for immutable Map
                            public void putAll(Map t) {
                                throw new UnsupportedOperationException();
                            }


                            // Do not need to implement for immutable Map
                            public Object remove(Object k) {
                                throw new UnsupportedOperationException();
                            }


                            public int size() {
                                int result = 0;
                                Enumeration keys = bundle.getKeys();
                                while (keys.hasMoreElements()) {
                                    keys.nextElement();
                                    result++;
                                }
                                return result;
                            }


                            public java.util.Collection values() {
                                ArrayList result = new ArrayList();
                                Enumeration keys = bundle.getKeys();
                                while (keys.hasMoreElements()) {
                                    result.add(
                                            bundle.getObject(keys.nextElement()));
                                }
                                return result;
                            }
                        };

            }

            if (null == resourceBundleMap) {
                resourceBundleMap = Collections.EMPTY_MAP;
            }

        }
        
        return resourceBundleMap;
    }

    // PENDING(rlubke): I'm sure there's a more efficient
    // way to handle this.
    private Resource findComponentResourceBundleLocaleMatch(FacesContext context, 
            String resourceName, String libraryName) {
        Resource result = null;
        ResourceBundle resourceBundle = null;
        int i;
        if (-1 != (i = resourceName.lastIndexOf("."))) {
            resourceName = resourceName.substring(0, i) +
                    ".properties";
            if (null != context) {
                result = context.getApplication().getResourceHandler().
                        createResource(resourceName, libraryName);
                InputStream propertiesInputStream = null;
                try {
                    propertiesInputStream = result.getInputStream();
                    resourceBundle = new PropertyResourceBundle(propertiesInputStream);
                } catch (IOException ex) {
                    Logger.getLogger(UIComponent.class.getName()).log(Level.SEVERE, null, ex);
                } finally{
                    if(null != propertiesInputStream){
                        try{
                            propertiesInputStream.close();
                        } catch(IOException ioe){
                            if (LOGGER.isLoggable(Level.SEVERE)) {
                                LOGGER.log(Level.SEVERE, null, ioe);
                            }
                        }
                    }
                }
            }
        }
        result = (null != resourceBundle) ? result : null;
        
        return result;
    }
    
    
    // This is necessary for JSF components that extend from UIComponent
    // directly rather than extending from UIComponentBase.  Such components
    // may need to have implementations provided for methods that originated
    // from a spec version more recent than the version with which the component
    // complies.  Currently this private property is only consulted in the
    // getValueExpression() method.
//    private boolean isUIComponentBase;
//    private boolean isUIComponentBaseIsSet = false;
//
//    private boolean isUIComponentBase() {
//        if (!isUIComponentBaseIsSet) {
//            isUIComponentBase = (this instanceof UIComponentBase);
//        }
//
//        return isUIComponentBase;
//    }


    // ------------------------------------------------- Tree Management Methods


    /**
     * 
Return a mutable
     * List representing the child {@link UIComponent}s
     * associated with this component.  The returned implementation must
     * support all of the standard and optional List
     * methods, plus support the following additional requirements:

     * 
     
  • The List implementation must implement the
     * java.io.Serializable interface.
    •  
  • Any attempt
     * to add a null must throw a NullPointerException
    • 
     * 
  • Any attempt to add an object that does not implement {@link
     * UIComponent} must throw a ClassCastException.
    •  
  • Whenever a
     * new child component is added, the parent property of
     * the child must be set to this component instance.  If the
     * parent property of the child was already non-null,
     * the child must first be removed from its previous parent (where
     * it may have been either a child or a facet).
    •  
  • Whenever an
     * existing child component is removed, the parent
     * property of the child must be set to null.
    • 

     * 
  • After the child component has
     *     been added to the view, {@link
     *     javax.faces.application.Application#publishEvent} must be
     *     called, passing {@link
     *     javax.faces.event.PostAddToViewEvent}.class as
     *     the first argument and the newly added component as the
     *     second argument if any the following cases are true.
    
     *
     *     
      

     *       
    • {@link
     *       javax.faces.context.FacesContext#getCurrentPhaseId} returns
     *       {@link javax.faces.event.PhaseId#RESTORE_VIEW} and partial
     *       state saving is enabled.
      • 

     *       
    • {@link javax.faces.context.FacesContext#isPostback}
     *       returns false and {@link
     *       javax.faces.context.FacesContext#getCurrentPhaseId} returns
     *       something other than {@link
     *       javax.faces.event.PhaseId#RESTORE_VIEW}
      • 

     *    
    

     * 
    • 

     * 

     */
    public abstract List getChildren();


    /**
     * 
Return the number of child {@link UIComponent}s that are
     * associated with this {@link UIComponent}.  If there are no
     * children, this method must return 0.  The method must not cause
     * the creation of a child component list.

     */
    public abstract int getChildCount();


    /**
     * 
Search for and
     * return the {@link UIComponent} with an id that
     * matches the specified search expression (if any), according to
     * the algorithm described below.


     * 
WARNING: The found
     * UIComponent instance, if any, is returned
     * without regard for its tree traversal context.
     * Retrieving an EL-bound attribute from the component is not safe.
     * EL expressions can contain implicit objects, such as
     * #{component}, which assume they are being evaluated
     * within the scope of a tree traversal context.  Evaluating
     * expressions with these kinds of implicit objects outside of a
     * tree traversal context produces undefined results.  See {@link
     * #invokeOnComponent} for a method that does
     * correctly account for the tree traversal context when operating
     * on the found UIComponent instance.  {@link #invokeOnComponent}
     * is also useful to find components given a simple clientId.
     *
     * 
Component identifiers are required to be unique within the scope of
     * the closest ancestor {@link NamingContainer} that encloses this
     * component (which might be this component itself).  If there are no
     * {@link NamingContainer} components in the ancestry of this component,
     * the root component in the tree is treated as if it were a
     * {@link NamingContainer}, whether or not its class actually implements
     * the {@link NamingContainer} interface.

     *
     * 
A search expression consists of either an identifier
     * (which is matched exactly against the id property of
     * a {@link UIComponent}, or a series of such identifiers linked by
     * the {@link UINamingContainer#getSeparatorChar} character value.
     * The search algorithm should operates as follows, though alternate
     * alogrithms may be used as long as the end result is the same:


     * 
    
     * 
  • Identify the {@link UIComponent} that will be the base for searching,
     *     by stopping as soon as one of the following conditions is met:
     *     
      
     *     
    • If the search expression begins with the the separator character
     *         (called an "absolute" search expression),
     *         the base will be the root {@link UIComponent} of the component
     *         tree.  The leading separator character will be stripped off,
     *         and the remainder of the search expression will be treated as
     *         a "relative" search expression as described below.
      • 
     *     
    • Otherwise, if this {@link UIComponent} is a
     *         {@link NamingContainer} it will serve as the basis.
      • 
     *     
    • Otherwise, search up the parents of this component.  If
     *         a {@link NamingContainer} is encountered, it will be the base.
     *         
      • 
     *     
    • Otherwise (if no {@link NamingContainer} is encountered)
     *         the root {@link UIComponent} will be the base.
      • 
     *     
    • 
     * 
  • The search expression (possibly modified in the previous step) is now
     *     a "relative" search expression that will be used to locate the
     *     component (if any) that has an id that matches, within
     *     the scope of the base component.  The match is performed as follows:
     *     
      
     *     
    • If the search expression is a simple identifier, this value is
     *         compared to the id property, and then recursively
     *         through the facets and children of the base {@link UIComponent}
     *         (except that if a descendant {@link NamingContainer} is found,
     *         its own facets and children are not searched).
      • 
     *     
    • If the search expression includes more than one identifier
     *         separated by the separator character, the first identifier is
     *         used to locate a {@link NamingContainer} by the rules in the
     *         previous bullet point.  Then, the findComponent()
     *         method of this {@link NamingContainer} will be called, passing
     *         the remainder of the search expression.
      • 
     *     
    • 
     * 

     *
     * @param expr Search expression identifying the {@link UIComponent}
     *  to be returned
     *
     * @return the found {@link UIComponent}, or null
     *  if the component was not found.
     *
     * @throws IllegalArgumentException if an intermediate identifier
     *  in a search expression identifies a {@link UIComponent} that is
     *  not a {@link NamingContainer}
     * @throws NullPointerException if expr
     *  is null
     */
    public abstract UIComponent findComponent(String expr);

    /**
     * 
Starting at this
     * component in the View hierarchy, search for a component with a
     * clientId equal to the argument clientId
     * and, if found, call the {@link
     * ContextCallback#invokeContextCallback} method on the argument
     * callback, passing the current {@link FacesContext}
     * and the found component as arguments. This method is similar to
     * {@link #findComponent} but it does not support the leading {@link
     * UINamingContainer#getSeparatorChar} syntax for searching from the
     * root of the View.

     *
     * 
The default implementation will first check if
     * this.getClientId() is equal to the argument
     * clientId.  If so, first call {@link #pushComponentToEL},
     * then call the {@link
     * ContextCallback#invokeContextCallback} method on the argument
     * callback, passing through the FacesContext argument
     * and passing this as the component argument.  Then call {@link #popComponentFromEL}.
     * If an Exception is thrown by the callback, wrap it
     * in a {@link FacesException} and re-throw it.  Otherwise, return
     * true.

     *
     * 
Otherwise, for each component returned by {@link
     * #getFacetsAndChildren}, call invokeOnComponent()
     * passing the arguments to this method, in order.  The first time
     * invokeOnComponent() returns true, abort traversing
     * the rest of the Iterator and return
     * true.

     *
     * 
When calling {@link ContextCallback#invokeContextCallback}
     * the implementation of this method must guarantee that the state
     * of the component passed to the callback correctly reflects the
     * component's position in the View hierarchy with respect to any
     * state found in the argument clientId.  For example,
     * an iterating component such as {@link UIData} will need to set
     * its row index to correctly reflect the argument
     * clientId before finding the appropriate child
     * component backed by the correct row.  When the callback returns,
     * either normally or by throwing an Exception the
     * implementation of this method must restore the state of the view
     * to the way it was before invoking the callback.

     *
     * 
If none of the elements from {@link
     * #getFacetsAndChildren} returned true from
     * invokeOnComponent(), return false.

     *
     * 
Simple usage example to find a component by
     * clientId.


* 

private UIComponent found = null;

private void doFind(FacesContext context, String clientId) {
  context.getViewRoot().invokeOnComponent(context, clientId,
      new ContextCallback() {
         public void invokeContextCallback(FacesContext context,
                                       UIComponent component) {
           found = component;
         }
      });
}
* 


     *
     *
     * @since 1.2
     *
     * @param context the {@link FacesContext} for the current request
     *
     * @param clientId the client identifier of the component to be passed
     * to the argument callback.
     *
     * @param callback an implementation of the Callback interface.
     *
     * @throws NullPointerException if any of the arguments are null
     *
     * @throws FacesException if the argument Callback throws an
     * Exception, it is wrapped in a FacesException and re-thrown.
     *
     * @return true if the a component with the given
     * clientId is found, the callback method was
     * successfully invoked passing that component as an argument, and
     * no Exception was thrown.  Returns false if no
     * component with the given clientId is found.
     *
     */

    public boolean invokeOnComponent(FacesContext context, String clientId,
            ContextCallback callback) throws FacesException {
        if (null == context || null == clientId || null == callback) {
            throw new NullPointerException();
        }

        boolean found = false;
        if (clientId.equals(this.getClientId(context))) {
            try {
                this.pushComponentToEL(context, this);
                callback.invokeContextCallback(context, this);
                return true;
            } catch (Exception e) {
                throw new FacesException(e);
            } finally {
                this.popComponentFromEL(context);
            }
        } else {
            Iterator itr = this.getFacetsAndChildren();

            while (itr.hasNext() && !found) {
                found = itr.next().invokeOnComponent(context, clientId,
                        callback);
            }
        }
        return found;
    }

    // ------------------------------------------------ Facet Management Methods


    /**
     * 
Return a mutable Map representing the facet
     * {@link UIComponent}s associated with this {@link UIComponent},
     * keyed by facet name (which must be a String).  The returned
     * implementation must support all of the standard and optional
     * Map methods, plus support the following additional
     * requirements:


     * 
    
     * 
  • The Map implementation must implement
     *     the java.io.Serializable interface.
    • 
     * 
  • Any attempt to add a null key or value must
     *     throw a NullPointerException.
    • 
     * 
  • Any attempt to add a key that is not a String must throw
     *     a ClassCastException.
    • 
     * 
  • Any attempt to add a value that is not a {@link UIComponent}
     *     must throw a ClassCastException.
    • 
     * 
  • Whenever a new facet {@link UIComponent} is added:
     *     
      
     *     
    • The parent property of the component must be set to
     *         this component instance.
      • 
     *     
    • If the parent property of the component was already
     *     non-null, the component must first be removed from its previous
     *     parent (where it may have been either a child or a facet).
      • 
     *     
    • 

     * 
  • Whenever an existing facet {@link UIComponent} is removed:
     *     
      
     *     
    • The parent property of the facet must be
     *         set to null.
      • 
     *     
    • 
     * 

     */
    public abstract Map getFacets();

    /**
     * 
Return the number of facet {@link UIComponent}s that are
     * associated with this {@link UIComponent}.  If there are no
     * facets, this method must return 0.  The method must not cause
     * the creation of a facet component map.

     *
     * 
For backwards compatability with classes that extend UIComponent
     * directly, a default implementation is provided that simply calls
     * {@link #getFacets} and then calls the size() method on the
     * returned Map.  A more optimized version of this method is
     * provided in {@link UIComponentBase#getFacetCount}.
     *
     * @since 1.2
     */
    public int getFacetCount() {
        return (getFacets().size());
    }



    /**
     * 
Convenience method to return the named facet, if it exists, or
     * null otherwise.  If the requested facet does not
     * exist, the facets Map must not be created.

     *
     * @param name Name of the desired facet
     */
    public abstract UIComponent getFacet(String name);


    /**
     * 
Return an Iterator over the facet followed by child
     * {@link UIComponent}s of this {@link UIComponent}.
     * Facets are returned in an undefined order, followed by
     * all the children in the order they are stored in the child list. If this
     * component has no facets or children, an empty Iterator
     * is returned.

     *
     * 
The returned Iterator must not support the
     * remove() operation.

     */
    public abstract Iterator getFacetsAndChildren();


    // -------------------------------------------- Lifecycle Processing Methods


    /**
     * 
Broadcast the specified {@link FacesEvent} to all registered
     * event listeners who have expressed an interest in events of this
     * type.  Listeners are called in the order in which they were
     * added.
  
     * 
If the event is an instance of 
     * {@link javax.faces.event.BehaviorEvent} and the current 
     * component is the source of the event
     * call {@link javax.faces.event.BehaviorEvent#getBehavior} to get the
     * {@link javax.faces.component.behavior.Behavior} for the event. 

     * Call {@link
     * javax.faces.component.behavior.Behavior#broadcast(javax.faces.event.BehaviorEvent)}
     * on the Behavior instance.

     *
     * @param event The {@link FacesEvent} to be broadcast
     *
     * @throws AbortProcessingException Signal the JavaServer Faces
     *  implementation that no further processing on the current event
     *  should be performed
     * @throws IllegalArgumentException if the implementation class
     *  of this {@link FacesEvent} is not supported by this component
     * @throws NullPointerException if event is
     * null
     */
    public abstract void broadcast(FacesEvent event)
        throws AbortProcessingException;


    /**
     * 
Decode any new state of this {@link UIComponent} from the
     * request contained in the specified {@link FacesContext}, and store
     * this state as needed.

     * 
During decoding, events may be enqueued for later processing
     * (by event listeners who have registered an interest),  by calling
     * queueEvent().

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void decode(FacesContext context);
    
    /**
     * 
Perform a tree visit starting at
     * this node in the tree.

     *
     * 

     *
     * 
UIComponent.visitTree() implementations do not invoke the
     * {@link VisitCallback} directly, but instead call {@link
     * VisitContext#invokeVisitCallback} to invoke the callback.  This
     * allows {@code VisitContext} implementations to provide optimized
     * tree traversals, for example by only calling the {@code
     * VisitCallback} for a subset of components.

     *
     * 
UIComponent.visitTree() implementations must call
     * UIComponent.pushComponentToEL() before performing the
     * visit and UIComponent.popComponentFromEL() after the
     * visit.

     *
     * @param context the VisitContext for this visit
     * @param callback the VisitCallback instance
     * whose visit method will be called
     * for each node visited.
     * @return component implementations may return true 
     *   to indicate that the tree visit is complete (eg. all components
     *   that need to be visited have been visited).  This results in
     *   the tree visit being short-circuited such that no more components
     *   are visited.
     *
     * 

     *
     * @see VisitContext#invokeVisitCallback VisitContext.invokeVisitCallback()
     *
     * @since 2.0
     */
    public boolean visitTree(VisitContext context, 
                             VisitCallback callback) {

        // First check to see whether we are visitable.  If not
        // short-circuit out of this subtree, though allow the
        // visit to proceed through to other subtrees.
        if (!isVisitable(context))
            return false;

        // Push ourselves to EL before visiting
        FacesContext facesContext = context.getFacesContext();
        pushComponentToEL(facesContext, null);

        try {
            // Visit ourselves.  Note that we delegate to the 
            // VisitContext to actually perform the visit.
            VisitResult result = context.invokeVisitCallback(this, callback);

            // If the visit is complete, short-circuit out and end the visit
            if (result == VisitResult.COMPLETE)
              return true;

            // Visit children if necessary
            if (result == VisitResult.ACCEPT) {
                Iterator kids = this.getFacetsAndChildren();

                while(kids.hasNext()) {
                    boolean done = kids.next().visitTree(context, callback);

                    // If any kid visit returns true, we are done.
                    if (done)
                        return true;
                }
            }
        }
        finally {
            // Pop ourselves off the EL stack
            popComponentFromEL(facesContext);
        }

        // Return false to allow the visit to continue
        return false;
    }

    /**
     * 
Return true if this
     * component should be visited, false otherwise.
     * Called by {@link UIComponent#visitTree UIComponent.visitTree()}
     * to determine whether this component satisfies the hints returned
     * by {@link javax.faces.component.visit.VisitContext#getHints}.


     * 


     * 
If this method returns false, the tree visited is
     * short-circuited such that neither the component nor any of its
     * descendents will be visited>
 

     * 
Custom {@code visitTree()} implementations may call this
     * method to determine whether the component is visitable before
     * performing any visit-related processing.

     *
     * 

     *
     * @since 2.0
     */
    protected boolean isVisitable(VisitContext context) {

        // VisitHints currently defines two hints that affect 
        // visitability: VIIST_RENDERED and VISIT_TRANSIENT.
        // Check for both of these and if set, verify that 
        // we comply.
        Set hints = context.getHints();

        if ((hints.contains(VisitHint.SKIP_UNRENDERED) && 
                !this.isRendered())                    ||
            (hints.contains(VisitHint.SKIP_TRANSIENT)  && 
                this.isTransient())) {
            return false;
        }

        return true;
    }

    /**
     * 
If our
     * rendered property is true, render the
     * beginning of the current state of this {@link UIComponent} to the
     * response contained in the specified {@link FacesContext}. 
     * Call {@link #pushComponentToEL(javax.faces.context.FacesContext,javax.faces.component.UIComponent)}.
     * Call {@link javax.faces.application.Application#publishEvent}, passing
     * {@link javax.faces.event.PreRenderComponentEvent}.class as the
     * first argument and the component instance to be rendered as the
     * second argument.


     * 
If a {@link Renderer} is associated with this {@link
     * UIComponent}, the actual encoding will be delegated to
     * {@link Renderer#encodeBegin(FacesContext, UIComponent)}.
     * 

     *
     * 
If our rendered property is
     * false, call {@link #pushComponentToEL(javax.faces.context.FacesContext,javax.faces.component.UIComponent)}
     * and return immediately.

     *
     * @param context {@link FacesContext} for the response we are creating
     *
     * @throws IOException if an input/output error occurs while rendering
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void encodeBegin(FacesContext context) throws IOException;


    /**
     * 
If our rendered property is true,
     * render the child {@link UIComponent}s of this {@link UIComponent}.
     * This method will only be called
     * if the rendersChildren property is true.

     *
     * 
If a {@link Renderer} is associated with this {@link UIComponent},
     * the actual encoding will be delegated to
     * {@link Renderer#encodeChildren(FacesContext, UIComponent)}.
     * If no {@link Renderer} is associated
     * with this {@link UIComponent}, iterate over each of the children of this
     * component and call 
     * {@link #encodeAll(javax.faces.context.FacesContext)}.

     *
     * @param context {@link FacesContext} for the response we are creating
     *
     * @throws IOException if an input/output error occurs while rendering
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void encodeChildren(FacesContext context) throws IOException;


    /**
     * 
If our
     * rendered property is true, render the
     * ending of the current state of this {@link UIComponent}.

     *
     * 
If a {@link Renderer} is associated with this {@link UIComponent},
     * the actual encoding will be delegated to
     * {@link Renderer#encodeEnd(FacesContext, UIComponent)}.

     *
     * 
Call {@link
     * UIComponent#popComponentFromEL}. before returning regardless of the value
     *  of the rendered property.

     *
     * @param context {@link FacesContext} for the response we are creating
     *
     * @throws IOException if an input/output error occurs while rendering
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void encodeEnd(FacesContext context) throws IOException;

    /**
     * 
If this component
     * returns true from {@link #isRendered}, take the
     * following action.

     *
     * 
Render this component and all its children that return
     * true from isRendered(), regardless of
     * the value of the {@link #getRendersChildren} flag.


     * @since 1.2
     *
     * @throws IOException if an input/output error occurs while rendering
     * @throws NullPointerException if context
     *  is null
     */
    public void encodeAll(FacesContext context) throws IOException {

        if (context == null) {
            throw new NullPointerException();
        }

        if (!isRendered()) {
            return;
        }

        encodeBegin(context);
        if (getRendersChildren()) {
            encodeChildren(context);
        } else if (this.getChildCount() > 0) {
            for (UIComponent kid : getChildren()) {
                kid.encodeAll(context);
            }
        }

        encodeEnd(context);

    }

    
    private static ArrayDeque _getComponentELStack(String keyName, Map contextAttributes)
    {
      ArrayDeque elStack = (ArrayDeque)contextAttributes.get(keyName);
      
      if (elStack == null)
      {
        elStack = new ArrayDeque();
        contextAttributes.put(keyName, elStack);
      }
      
      return elStack;
    }
    
    //private UIComponent previouslyPushed = null;
    //private UIComponent previouslyPushedCompositeComponent = null;
    //private boolean pushed;
    //private int depth;

    /**
     * 
Push the current
     * UIComponent this to the {@link FacesContext}
     * attribute map using the key {@link #CURRENT_COMPONENT} saving the previous
     * UIComponent associated with {@link #CURRENT_COMPONENT} for a
     * subsequent call to {@link #popComponentFromEL}.

     *
     * This method and popComponentFromEL() form the basis for
     * the contract that enables the EL Expression "#{component}" to
     * resolve to the "current" component that is being processed in the
     * lifecycle.  The requirements for when pushComponentToEL() and
     * popComponentFromEL() must be called are specified as
     * needed in the javadoc for this class.

     *
     * 
After
     * pushComponentToEL() returns, a call to {@link
     * #getCurrentComponent} must return this
     * UIComponent instance until
     * popComponentFromEL() is called, after which point
     * the previous UIComponent instance will be returned
     * from getCurrentComponent()

     *
     * @param context the {@link FacesContext} for the current request
     * @param component the component to push to the EL.  If
     *  component is null the UIComponent
     *  instance that this call was invoked upon will be pushed to the EL.
     *
     * @throws NullPointerException if context is null
     *
     * @see javax.faces.context.FacesContext#getAttributes()
     *
     * @since 2.0
     */
    public final void pushComponentToEL(FacesContext context, UIComponent component) {

        if (context == null) {
            throw new NullPointerException();
        }

        if (null == component) {
            component = this;
        }

        Map contextAttributes = context.getAttributes();
        ArrayDeque componentELStack = _getComponentELStack(_CURRENT_COMPONENT_STACK_KEY,
                                                               contextAttributes);
        componentELStack.push(component);
        component._isPushedAsCurrentRefCount++;
        
        // we only do this because of the spec
        boolean setCurrentComponent = false;
        String val = context.getExternalContext().getInitParameter(UIComponent.HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME);
        setCurrentComponent = Boolean.valueOf(val);
        if (setCurrentComponent) {
            contextAttributes.put(UIComponent.CURRENT_COMPONENT, component);
        }
        
        // if the pushed component is a composite component, we need to update that
        // stack as well
        if (UIComponent.isCompositeComponent(component))
        {
          _getComponentELStack(_CURRENT_COMPOSITE_COMPONENT_STACK_KEY,
                               contextAttributes).push(component);

          // we only do this because of the spec
          if (setCurrentComponent) {
              contextAttributes.put(UIComponent.CURRENT_COMPOSITE_COMPONENT, component);
          }
        }
    }

  // track whether we have been pushed as current in order to handle mismatched pushes and
  // pops of EL context stack.  We use a counter to handle cases where the same component
  // is pushed on multiple times
  private int _isPushedAsCurrentRefCount = 0;
  
  // key used to look up current component stack if FacesContext attributes
  private static final String _CURRENT_COMPONENT_STACK_KEY = 
                                                    "javax.faces.component.CURRENT_COMPONENT_STACK";
  
  // key used to look up current composite component stack if FacesContext attributes
  private static final String _CURRENT_COMPOSITE_COMPONENT_STACK_KEY = 
                                          "javax.faces.component.CURRENT_COMPOSITE_COMPONENT_STACK";
  

    /**
     * 
Pop the current
     * UIComponent from the {@link FacesContext} attributes map
     * so that the previous UIComponent, if any, becomes the current
     * component.

     *
     * @param context the {@link FacesContext} for the current request
     * 
     * @throws NullPointerException if context is null
     *
     * @see javax.faces.context.FacesContext#getAttributes()
     *
     * @since 2.0
     */
    public final void popComponentFromEL(FacesContext context)
    {
      if (context == null)
      {
        throw new NullPointerException();
      }

      // detect cases where the stack has become unbalanced.  Due to how UIComponentBase
      // implemented pushing and pooping of components from the ELContext, components that
      // overrode just one of encodeBegin or encodeEnd, or only called super in one case
      // will become unbalanced.  Detect and correct for those cases here.
 
      // detect case where push was never called.  In that case, pop should be a no-op
      if (_isPushedAsCurrentRefCount < 1) {
          return;
      }
           
      Map contextAttributes = context.getAttributes();
      
      ArrayDeque componentELStack = _getComponentELStack(_CURRENT_COMPONENT_STACK_KEY,
                                                             contextAttributes);
      
      // check for the other unbalanced case, a component was pushed but never popped.  Keep
      // popping those components until we get to our component
      for (UIComponent topComponent = componentELStack.peek();
           topComponent != this;
           topComponent = componentELStack.peek())
      {
          topComponent.popComponentFromEL(context);
      }
      
      // pop ourselves off of the stack
      componentELStack.pop();
      _isPushedAsCurrentRefCount--;

        boolean setCurrentComponent = false;
        String val = context.getExternalContext().getInitParameter(UIComponent.HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME);
        setCurrentComponent = Boolean.valueOf(val);

      
      // update the current component with the new top of stack.  We only do this because of the spec
        if (setCurrentComponent) {
            contextAttributes.put(UIComponent.CURRENT_COMPONENT, componentELStack.peek());
        }
      
      // if we're a composite component, we also have to pop ourselves off of the
      // composite stack
      if (UIComponent.isCompositeComponent(this))
      {
        ArrayDeque compositeELStack=_getComponentELStack(_CURRENT_COMPOSITE_COMPONENT_STACK_KEY,
                                                             contextAttributes);
        if (!compositeELStack.isEmpty()) {
            compositeELStack.pop();
        }        

        // update the current composite component with the new top of stack.
          // We only do this because of the spec
        if (setCurrentComponent) {
              contextAttributes.put(UIComponent.CURRENT_COMPOSITE_COMPONENT, compositeELStack.peek());
        }
      }
    }
    
    // It is safe to cache this because components never go from being
    // composite to non-composite.
    private transient Boolean isCompositeComponent = null;


    /**
     * 
Return true if
     * component is a composite component, otherwise
     * false.

     *
     * @param component the {@link UIComponent} to test
     *
     * @throws NullPointerException if component is null
     * @since 2.0
     */
    public static boolean isCompositeComponent(UIComponent component) {

        if (component == null) {
            throw new NullPointerException();
        }
        boolean result = false;
        if (null != component.isCompositeComponent) {
            result = component.isCompositeComponent.booleanValue();
        } else {
            result = component.isCompositeComponent =
                    (component.getAttributes().containsKey(
                               Resource.COMPONENT_RESOURCE_KEY));
        }
        return result;

    }


    /**
     * 

     * Finds the nearest composite component parent of the specified component.
     * 

     *
     * @param component the component from which to start the search from
     *
     * @return if component is null, return
     *  null, otherwise search the component's parent hierachy
     *  for the nearest parent composite component.  If no parent composite
     *  component is found, return null
     *
     * @since 2.0
     */
    public static UIComponent getCompositeComponentParent(UIComponent component) {

        if (component == null) {
            return null;
        } else {
            if (component.compositeParent != null) {
                return component.compositeParent;
            }
            UIComponent parent = component.getParent();
            while (parent != null) {
                if (UIComponent.isCompositeComponent(parent)) {
                    if (component.isInView()) {
                        component.compositeParent = parent;
                    }
                    return parent;
                }
                parent = parent.getParent();
            }
            return null;
        }
        
    }


    /**
     * 
Return the UIComponent
     * instance that is currently processing.  This is equivalent to
     * evaluating the EL expression "#{component}" and
     * doing a getValue operation on the resultant
     * ValueExpression.

     *
     * 
This method must return
     * null if there is no currently processing
     * UIComponent

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     *
     * @since 2.0
     */
    public static UIComponent getCurrentComponent(FacesContext context) {
        Map contextAttributes = context.getAttributes();
        ArrayDeque componentELStack = _getComponentELStack(_CURRENT_COMPONENT_STACK_KEY,
                                                               contextAttributes);

      return componentELStack.peek();
    }


    /**
     * 
Return the closest ancestor
     * component, relative to the component returned from {@link
     * #getCurrentComponent}, that is a composite component, or
     * null if no such component exists.

     *
     * @param context {@link FacesContext} for the request we are processing
     * 
     * @throws NullPointerException if context
     *  is null
     *
     * @since 2.0
     */
    public static UIComponent getCurrentCompositeComponent(FacesContext context) {
      // return (UIComponent)context.getAttributes().get(UIComponent.CURRENT_COMPOSITE_COMPONENT);
        Map contextAttributes = context.getAttributes();
        ArrayDeque compositeELStack = _getComponentELStack(_CURRENT_COMPOSITE_COMPONENT_STACK_KEY,
                                                             contextAttributes);
        return compositeELStack.peek();
    }
    
    // -------------------------------------------------- Event Listener Methods


    /**
     * 
Add the specified {@link FacesListener} to the set of listeners
     * registered to receive event notifications from this {@link UIComponent}.
     * It is expected that {@link UIComponent} classes acting as event sources
     * will have corresponding typesafe APIs for registering listeners of the
     * required type, and the implementation of those registration methods
     * will delegate to this method.  For example:

     * 
     * public class FooEvent extends FacesEvent { ... }
     *
     * public interface FooListener extends FacesListener {
     *   public void processFoo(FooEvent event);
     * }
     *
     * public class FooComponent extends UIComponentBase {
     *   ...
     *   public void addFooListener(FooListener listener) {
     *     addFacesListener(listener);
     *   }
     *   public void removeFooListener(FooListener listener) {
     *     removeFacesListener(listener);
     *   }
     *   ...
     * }
     * 

     *
     * @param listener The {@link FacesListener} to be registered
     *
     * @throws NullPointerException if listener
     *  is null
     */
    protected abstract void addFacesListener(FacesListener listener);


    /**
     * 
Return an array of registered {@link FacesListener}s that are
     * instances of the specified class.  If there are no such registered
     * listeners, a zero-length array is returned.  The returned
     * array can be safely be cast to an array strongly typed to
     * an element type of clazz.

     *
     * @param clazz Class that must be implemented by a {@link FacesListener}
     *  for it to be returned
     *
     * @throws IllegalArgumentException if class is not,
     *  and does not implement, {@link FacesListener}
     * @throws NullPointerException if clazz
     *  is null
     */
    protected abstract FacesListener[] getFacesListeners(Class clazz);


    /**
     * 
Remove the specified {@link FacesListener} from the set of listeners
     * registered to receive event notifications from this {@link UIComponent}.
     *
     * @param listener The {@link FacesListener} to be deregistered
     *
     * @throws NullPointerException if listener
     *  is null
     */
    protected abstract void removeFacesListener(FacesListener listener);


    /**
     * 
Queue an event for broadcast at the end of the current request
     * processing lifecycle phase.  The default implementation in
     * {@link UIComponentBase} must delegate this call to the
     * queueEvent() method of the parent {@link UIComponent}.

     *
     * @param event {@link FacesEvent} to be queued
     *
     * @throws IllegalStateException if this component is not a
     *  descendant of a {@link UIViewRoot}
     * @throws NullPointerException if event
     *  is null
     */
    public abstract void queueEvent(FacesEvent event);


    /**
     * 
This implementation throws
     * UnsupportedOperationException and is provided
     * for the sole purpose of not breaking existing applications that extend
     * this class.  {@link UIComponentBase} provides the implementation of
     * this method.

     *
     * @since 2.1
     */
    public void subscribeToEvent(Class eventClass,
                                          ComponentSystemEventListener componentListener) {
        throw new UnsupportedOperationException();
    }

    /**
     * 
This implementation throws
     * UnsupportedOperationException and is provided
     * for the sole purpose of not breaking existing applications that extend
     * this class.  {@link UIComponentBase} provides the implementation of
     * this method.

     *
     * @since 2.1
     */
    public void unsubscribeFromEvent(Class eventClass,
                                              ComponentSystemEventListener componentListener) {
        throw new UnsupportedOperationException();
    }

    /**
     * 
This implementation throws
     * UnsupportedOperationException and is provided
     * for the sole purpose of not breaking existing applications that extend
     * this class.  {@link UIComponentBase} provides the implementation of
     * this method.

     *
     * @since 2.1
     */
    public List getListenersForEventClass(Class eventClass) {
        throw new UnsupportedOperationException();
    }



    /**
     * 
Starting with "this", return the closest 
     * component in the ancestry that is a NamingContainer
     * or null if none can be found.

     *
     * @since 2.0
     */
    public UIComponent getNamingContainer() {
        UIComponent namingContainer = this;
        while (namingContainer != null) {
            if (namingContainer instanceof NamingContainer) {
                return namingContainer;
            }
            namingContainer = namingContainer.getParent();
        }
        return null;
    }

    // ------------------------------------------------ Lifecycle Phase Handlers


    /**
     * 
Perform the
     * component tree processing required by the Restore View
     * phase of the request processing lifecycle for all facets of this
     * component, all children of this component, and this component
     * itself, as follows.
 
     
  • Call the restoreState()
     * method of this component.
    •  
     *
     * 
  • Call
     * {@link UIComponent#pushComponentToEL}.  
    • 

     * 
  • Call the processRestoreState() method of all
     * facets and children of this {@link UIComponent} in the order
     * determined by a call to getFacetsAndChildren().
     * After returning from the
     * processRestoreState() method on a child or facet,
     * call {@link UIComponent#popComponentFromEL}
    • 

     * 

     *
     * 
This method may not be called if the state saving method is
     * set to server.

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void processRestoreState(FacesContext context,
                                             Object state);


    /**
     * 
Perform the
     * component tree processing required by the Apply Request
     * Values phase of the request processing lifecycle for all
     * facets of this component, all children of this component, and
     * this component itself, as follows.


     * 
    
     * 
  • If the rendered property of this {@link UIComponent}
     *     is false, skip further processing.
    • 
     * 
  • Call {@link #pushComponentToEL}.
    • 
     * 
  • Call the processDecodes() method of all facets
     *     and children of this {@link UIComponent}, in the order determined
     *     by a call to getFacetsAndChildren().
    • 

     * 
  • Call the decode() method of this component.
    • 

     * 
  • Call {@link #popComponentFromEL} from inside of a
     * finally block, just before returning.
    • 



     * 
  • If a RuntimeException is thrown during
     *     decode processing, call {@link FacesContext#renderResponse}
     *     and re-throw the exception.
    • 
     * 

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void processDecodes(FacesContext context);

    /**
     * 
The default implementation performs
     * the following action.  If the argument event is an
     * instance of {@link PostRestoreStateEvent}, call
     * this.{@link #getValueExpression} passing the literal
     * string “binding”, without the quotes, as the
     * argument.  If the result is non-null, set the value
     * of the ValueExpression to be this.

     */ 

    public void processEvent(ComponentSystemEvent event) throws AbortProcessingException {
        if (event instanceof PostRestoreStateEvent) {
	    assert(this == event.getComponent());
            // if this component has a component value reference expression,
            // make sure to populate the ValueExpression for it.
            ValueExpression valueExpression;
            if (null != (valueExpression = this.getValueExpression("binding"))) {
                valueExpression.setValue(FacesContext.getCurrentInstance().getELContext(), 
                        this);
            }
            isCompositeComponent = null;

        }
    }
    
    


    /**
     * 
Perform the component
     * tree processing required by the Process Validations
     * phase of the request processing lifecycle for all facets of this
     * component, all children of this component, and this component
     * itself, as follows.


     * 
    
     * 
  • If the rendered property of this {@link UIComponent}
     *     is false, skip further processing.
    • 
     * 
  • Call {@link #pushComponentToEL}.
    • 
     * 
  • Call the processValidators() method of all facets
     *     and children of this {@link UIComponent}, in the order determined
     *     by a call to getFacetsAndChildren().
    • 

     * 
  • After returning from
     * calling getFacetsAndChildren() call {@link
     * UIComponent#popComponentFromEL}.
    •  

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void processValidators(FacesContext context);


    /**
     * 
Perform the
     * component tree processing required by the Update Model
     * Values phase of the request processing lifecycle for all
     * facets of this component, all children of this component, and
     * this component itself, as follows.
 

     * 
     

     * 
  • If the rendered property of this {@link
     * UIComponent} is false, skip further processing.
    • 

     * 
  • Call {@link
     * #pushComponentToEL}.
    • 

     * 
  • Call the processUpdates() method of all facets
     * and children of this {@link UIComponent}, in the order determined
     * by a call to getFacetsAndChildren().  After returning from the
     * processUpdates() method on a child or facet, call
     * {@link UIComponent#popComponentFromEL}
    • 
 
    * 

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract void processUpdates(FacesContext context);


    /**
     * 
Perform the
     * component tree processing required by the state saving portion of
     * the Render Response phase of the request processing
     * lifecycle for all facets of this component, all children of this
     * component, and this component itself, as follows.


     * 
    
     *
     * 
  • consult the transient property of this
     * component.  If true, just return null.
    • 

     * 
  • Call {@link
     * #pushComponentToEL}.
    • 

     * 
  • Call the processSaveState() method of all facets
     * and children of this {@link UIComponent} in the order determined
     * by a call to getFacetsAndChildren(), skipping
     * children and facets that are transient.  Ensure that {@link
     * #popComponentFromEL} is called correctly after each child or
     * facet.
    • 
     *
     * 
  • Call the saveState() method of this component.
    • 
     *
     * 
  • Encapsulate the child state and your state into a
     * Serializable Object and return it.
    •  
     *
     * 

     *
     * 
This method may not be called if the state saving method is
     * set to server.

     *
     * @param context {@link FacesContext} for the request we are processing
     *
     * @throws NullPointerException if context
     *  is null
     */
    public abstract Object processSaveState(FacesContext context);


    // ----------------------------------------------------- Convenience Methods


    /**
     * 
Convenience method to return the {@link FacesContext} instance
     * for the current request.

     */
    protected abstract FacesContext getFacesContext();


    /**
     * 
Convenience method to return the {@link Renderer} instance
     * associated with this component, if any; otherwise, return
     * null.

     *
     * @param context {@link FacesContext} for the current request
     */
    protected abstract Renderer getRenderer(FacesContext context);


    // --------------------------------------------------------- Package Private


    static final class ComponentSystemEventListenerAdapter
       implements ComponentSystemEventListener, SystemEventListener, StateHolder, FacesWrapper {

        ComponentSystemEventListener wrapped;
        Class instanceClass;


        // -------------------------------------------------------- Constructors


        ComponentSystemEventListenerAdapter() {

            // necessary for state saving

        }


        ComponentSystemEventListenerAdapter(ComponentSystemEventListener wrapped,
                                            UIComponent component) {

            this.wrapped = wrapped;
            this.instanceClass = component.getClass();

        }


        // ------------------------------------ Methods from SystemEventListener


        public void processEvent(SystemEvent event) throws AbortProcessingException {

            wrapped.processEvent((ComponentSystemEvent) event);

        }

        // ------------------------------------ Methods from SystemEventListener


        public void processEvent(ComponentSystemEvent event) throws AbortProcessingException {

            wrapped.processEvent(event);

        }
        public boolean isListenerForSource(Object component) {

            if (wrapped instanceof SystemEventListener) {
                return ((SystemEventListener) wrapped).isListenerForSource(component);
            } else {
                return instanceClass.isAssignableFrom(component.getClass());
            }

        }


        // -------------------------------------------- Methods from StateHolder

        public Object saveState(FacesContext context) {

            if (context == null) {
                throw new NullPointerException();
            }
            return new Object[] {
                  ((wrapped instanceof UIComponent) ? null : new StateHolderSaver(context, wrapped)),
                  instanceClass
            };

        }


        public void restoreState(FacesContext context, Object state) {

            if (context == null) {
                throw new NullPointerException();
            }
            if (state == null) {
                return;
            }
            Object[] s = (Object[]) state;
            Object listener = s[0];
            wrapped = (ComponentSystemEventListener) ((listener == null)
                                                      ? UIComponent .getCurrentComponent(context)
                                                      : ((StateHolderSaver) listener).restore(context));
            instanceClass = (Class) s[1];
            
        }


        public boolean isTransient() {

            if (wrapped instanceof StateHolder) {
                return ((StateHolder) wrapped).isTransient();
            }
            return false;

        }


        public void setTransient(boolean newTransientValue) {

            // no-op

        }


        // ------------------------------------------- Methods from FacesWrapper


        public ComponentSystemEventListener getWrapped() {

            return wrapped;

        }


        // ------------------------------------------------------ Public Methods


        @Override
        public int hashCode() {

            return (wrapped.hashCode() ^ instanceClass.hashCode());

        }

        @Override
        public boolean equals(Object obj) {

            if (!(obj instanceof ComponentSystemEventListenerAdapter)) {
                return false;
            }
            ComponentSystemEventListenerAdapter in =
                  (ComponentSystemEventListenerAdapter) obj;
            return (wrapped.equals(in.wrapped)
                    && instanceClass.equals(in.instanceClass));
            
        }
    } // END ComponentSystemEventListenerAdapter

}
    

    

    
            
    
            







    
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