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The JGoodies Binding library connects object properties to Swing user interface components. And it helps you represent the state and behavior of a presentation independently of the GUI components used in the interface.

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/*
 * Copyright (c) 2002-2013 JGoodies Software GmbH. All Rights Reserved.
 *
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package com.jgoodies.binding;

import static com.jgoodies.common.base.Preconditions.checkArgument;
import static com.jgoodies.common.base.Preconditions.checkNotNull;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyVetoException;
import java.util.HashMap;
import java.util.Map;

import javax.swing.JComponent;

import com.jgoodies.binding.adapter.Bindings;
import com.jgoodies.binding.beans.BeanAdapter;
import com.jgoodies.binding.beans.BeanUtils;
import com.jgoodies.binding.beans.Model;
import com.jgoodies.binding.beans.PropertyAccessException;
import com.jgoodies.binding.beans.PropertyNotBindableException;
import com.jgoodies.binding.beans.PropertyNotFoundException;
import com.jgoodies.binding.beans.PropertyUnboundException;
import com.jgoodies.binding.internal.IPresentationModel;
import com.jgoodies.binding.value.AbstractValueModel;
import com.jgoodies.binding.value.AbstractWrappedValueModel;
import com.jgoodies.binding.value.BufferedValueModel;
import com.jgoodies.binding.value.ComponentValueModel;
import com.jgoodies.binding.value.DefaultComponentValueModel;
import com.jgoodies.binding.value.Trigger;
import com.jgoodies.binding.value.ValueHolder;
import com.jgoodies.binding.value.ValueModel;
import com.jgoodies.common.base.Objects;

/**
 * The standard base class to implement the Presentation Model pattern,
 * that represents the state and behavior of a presentation independently
 * of the GUI components used in the interface. This
 * pattern
 * is described in Martin Fowler's upcoming
 * addition
 * to his "Patterns of Enterprise Application Architecture". More details
 * around this implementation of the Presentation Model pattern and a 3-tier
 * Swing client architecture with a presentation model layer can be found in
 * the JGoodies
 * Binding presentation. This architecture is supported
 * by the JGoodies Binding library.

* * This class minimizes the effort required to bind, edit, * buffer, and observe the bound properties of an exchangeable bean. * Therefore it provides five groups of features that are described below:

    *
  1. adapt bean properties, *
  2. change the adapted bean, *
  3. buffer values, *
  4. observe the buffering state, and *
  5. track changes in adapted bean properties. *

* * Typically this class will be extended to add custom models, Actions, * presentation logic, model operations and other higher-level behavior. * However, in simple cases you can use this class as-is. * Several methods are intended to be used as-is and a typical subclass * should not modify them. For example #isChanged, #isBuffering, * #getBean, #setBean, #getBeanChannel, #getModel, #getBufferedModel, * #getTriggerChannel, #setTriggerChannel, #triggerCommit and #triggerFlush.

* * Adapting Bean Properties
* The method {@link #getModel(String)} vends ValueModels that adapt * a bound bean property of an exchangeable bean. These ValueModels will be * requested from an underlying BeanAdapter. * To get such a model you specify the name of the bean property. * All properties adapted must be read-write and must comply with * the Java Bean coding conventions. * In case you need to adapt a read-only or write-only property, * or if the bean uses custom names for the reader and writer, * use {@link #getModel(String, String, String)}. * Also note that you must not mix calls to these methods for the same * property name. For details see the JavaDoc class comment in * {@link com.jgoodies.binding.beans.BeanAdapter}.

* * Changing the Adapted Bean
* The adapted bean is not stored in this PresentationModel. * Instead it is held by a ValueModel, the bean channel * - just as in the PropertyAdapter and BeanAdapter. * This indirection enables you to manage the adapted bean outside * of this PresentationModel, and it enables you to share bean channels * between multiple PresentationModels, PropertyAdapters, and BeanAdapters. * The bean channel is used by all adapting models created * by the factory methods {@code #getModel}. * You can get and set the current bean by means of {@code #getBean} * and {@code #setBean}. Or you can set a new value to the bean channel.

* * PresentationModel fires three PropertyChangeEvents if the bean changes: * beforeBean, bean and afterBean. This is useful * when sharing a bean channel and you must perform an operation before * or after other listeners handle a bean change. Since you cannot rely * on the order listeners will be notified, only the beforeBean * and afterBean events are guaranteed to be fired before and * after the bean change is fired. * Note that {@code #getBean()} returns the new bean before * any of these three PropertyChangeEvents is fired. Therefore listeners * that handle these events must use the event's old and new value * to determine the old and new bean. * The order of events fired during a bean change is:

    *
  1. the bean channel fires a value change, *
  2. this model fires a beforeBean change, *
  3. this model fires the bean change, *
  4. this model fires an afterBean change. *
* * Buffering Values
* At the core of this feature are the methods {@link #getBufferedModel(String)} * that vend BufferedValueModels that wrap an adapted bean property. * The buffer can be committed or flushed using {@code #triggerCommit} * and {@code #triggerFlush} respectively.

* * The trigger channel is provided as a bound Java bean property * triggerChannel that must be a non-{@code null} * {@code ValueModel} with values of type {@code Boolean}. * Attempts to read or write other value types may be rejected * with runtime exceptions. * By default the trigger channel is initialized as an instance of * {@code Trigger}. As an alternative it can be set in the constructor.

* * Observing the Buffering State
* This class also provides support for observing the buffering state * of the BufferedValueModels created with this model. The buffering state * is useful for UI actions and operations that are enabled or disabled * if there are pending changes, for example on OK or APPLY button. * API users can request the buffering state via {@code #isBuffering} * and can observe the bound property buffering.

* * Tracking Changes in the Adapted Bean
* PresentationModel provides support for observing bean property changes * and it tracks all changes to report the overall changed state. * The latter is useful to detect whether the bean has changed at all, * for example to mark the bean as dirty, so it will be updated in a database. * API users can request the changed state via {@code #isChanged} * and can observe the bound property changed. * If you want to track changes of other ValueModels, bean properties, * or of submodels, register them using {@code #observeChanged}. * To reset the changed state invoke {@code #resetChanged}. * In case you track the changed state of submodels you should override * {@code #resetChanged} to reset the changed state in these submodels.

* * The changed state changes once only (from false to true). If you need * instant notifications about changes in the properties of the target bean, * you can register PropertyChangeListeners with this model. This is useful * if you change the bean and don't want to move your listeners from one bean * to the other. And it's useful if you want to observe multiple bean * properties at the same time. These listeners are managed by the method set * {@code #addBeanPropertyChangeListener} and * {@code #removeBeanPropertyChangeListener}. * Listeners registered via these methods will be removed * from the old bean before the bean changes and will be re-added after * the new bean has been set. Therefore these listeners will be notified * about changes only if the current bean changes a property. They won't be * notified if the bean changes - and in turn the property value. If you want * to observes property changes caused by bean changes too, register with * the adapting ValueModel as returned by {@code #getModel(String)}.

* * Instance Creation
* PresentationModel can be instantiated using four different constructors: * you can specify the target bean directly, or you can provide a * bean channel to access the bean indirectly. * In the latter case you specify a {@code ValueModel} * that holds the bean that in turn holds the adapted property. * In both cases the target bean is accessed indirectly through * the bean channel. In both cases you can specify a custom trigger channel, * or you can use a default trigger channel.

* * Note: This PresentationModel provides bound bean properties * and you can register and unregister PropertyChangeListers as usual using * {@code #addPropertyChangeListener} and * {@code #removePropertyChangeListener}. Do not mix up * the model listeners with the listeners registered with the bean.

* * Warning: PresentationModels register a * PropertyChangeListener with the target bean. Hence, a bean has a reference * to all PresentationModels that hold it as target bean. To avoid memory leaks * it is recommended to remove this listener if the bean lives much longer * than the PresentationModel, enabling the garbage collector to remove * the PresentationModel. * Setting a PresentationModel's target bean to null removes this listener, * which in turn clears the reference from the bean to the PresentationModel. * To do so, you can call {@code setBean(null)} or set the * bean channel's value to null. * As an alternative you can use event listener lists in your beans * that implement references with {@code WeakReference}. * Setting the bean to null has side effects, which is fine in most cases. * However, you can release all listeners by calling {@code #release}.

* * TODO: Further improve the class comment.

* * TODO: Consider adding a feature to ensure that update notifications * are performed in the event dispatch thread. In case the adapted bean * is changed in a thread other than the event dispatch thread, such * a feature would help complying with Swing's single thread rule. * The feature could be implemented by an extended PropertyChangeSupport.

* * TODO: I plan to improve the support for adapting beans that do not fire * PropertyChangeEvents. This affects the classes PropertyAdapter, BeanAdapter, * and PresentationModel. Basically the PropertyAdapter and the BeanAdapter's * internal SimplePropertyAdapter's shall be able to optionally self-fire * a PropertyChangeEvent in case the bean does not. There are several * downsides with self-firing events compared to bound bean properties. * See Issue * 49 for more information about the downsides.

* * The observeChanges constructor parameter shall be replaced by a more * fine-grained choice to not observe (former observeChanges=false), * to observe bound properties (former observeChanges=true), and a new * setting for self-firing PropertyChangeEvents if a value is set. * The latter case may be further split up to specify how the * self-fired PropertyChangeEvent is created: *

    *
  1. oldValue=null, newValue=null *
  2. oldValue=null, newValue=the value set *
  3. oldValue=value read before the set, newValue=the value set *
  4. oldValue=value read before the set, newValue=value read after the set *
* * @author Karsten Lentzsch * @version $Revision: 1.26 $ * * @see com.jgoodies.binding.beans.BeanAdapter * @see com.jgoodies.binding.value.ValueModel * @see com.jgoodies.binding.beans.PropertyAdapter * @see com.jgoodies.binding.value.Trigger * * @param the type of the bean managed by this PresentationModel */ public class PresentationModel extends Model implements IPresentationModel { // Property Names ********************************************************* /** * The property name used in the PropertyChangeEvent that is fired * before the bean property fires its PropertyChangeEvent. * Useful to perform an operation before listeners that handle the * bean change are notified. See also the class comment. */ public static final String PROPERTY_BEFORE_BEAN = "beforeBean"; /** * The name of the read-write bound property that holds the target bean. * * @see #getBean() * @see #setBean(Object) */ public static final String PROPERTY_BEAN = "bean"; /** * The property name used in the PropertyChangeEvent that is fired * after the bean property fires its PropertyChangeEvent. * Useful to perform an operation after listeners that handle the * bean change are notified. See also the class comment. */ public static final String PROPERTY_AFTER_BEAN = "afterBean"; /** * The name of the read-write bound bean property for the * trigger channel that is shared by all PropertyAdapters * that are created via {@code #getBufferedModel}. * * @see #getTriggerChannel() * @see #setTriggerChannel(ValueModel) * @see #getBufferedModel(String) */ public static final String PROPERTY_TRIGGERCHANNEL = "triggerChannel"; /** * The name of the read-only bound bean property that indicates * whether one of the buffered models is buffering. * * @see #isBuffering() * @see #getBufferedModel(String) */ public static final String PROPERTY_BUFFERING = "buffering"; /** * The name of the read-only bound bean property that * indicates whether one of the observed models has changed. * * @see #isChanged() * @see #resetChanged() * @see #observeChanged(ValueModel) * @see #observeChanged(Object, String) */ public static final String PROPERTY_CHANGED = "changed"; // Fields ***************************************************************** /** * Refers to the BeanAdapter that provides all underlying behavior * to vend adapting ValueModels, track bean changes, and to register * with bound bean properties. */ private final BeanAdapter beanAdapter; /** * Holds a three-state trigger channel that can be used to trigger * commit and reset events in instances of BufferedValueModel. * The trigger value is changed to true in {@code #triggerCommit} * and is changed to false in {@code #triggerFlush}.

* * The trigger channel is initialized as a {@code Trigger} * but may be replaced by any other ValueModel that accepts booleans. * * @see #getTriggerChannel() * @see #setTriggerChannel(ValueModel) * @see #getBufferedModel(String) */ private ValueModel triggerChannel; /** * Maps property names to instances of the inner class WrappedBuffer. * These hold a BufferedValueModel associated with the property name, * as well as an optional getter and setter name. These accessor names * are used to check that multiple calls to {@code #getBufferedModel} * use the same getter and setter for a given property name.

* * The indirectly stored BufferedValueModel are checked whenever * the buffering state is updated. And these model's trigger channel * is updated when the PresentationModel gets a new trigger channel. * * @see #getBufferedModel(String) * @see #getBufferedModel(String, String, String) * @see #isBuffering() * @see #setTriggerChannel(ValueModel) */ private final Map wrappedBuffers; /** * Listens to value changes and validates this model. * The validation result is available in the validationResultHolder.

* * Also listens to changes of the buffering property in * {@code BufferedValueModel}s and updates the buffering state * - if necessary. */ private final PropertyChangeListener bufferingUpdateHandler; /** * Indicates whether a registered buffered model has a pending change, * in other words whether any of the values has been edited or not. */ private boolean buffering = false; /** * Listens to property changes and updates the changed property. */ private final PropertyChangeListener changedUpdateHandler; /** * Indicates whether a registered model has changed. */ private boolean changed = false; /** * Maps property names to instances of ComponentValueModel. * Used to ensure that multiple calls to #getComponentModel * return the same instance. * * @see #getComponentModel(String) */ private final Map componentModels; /** * Maps property names to instances of ComponentValueModel. * Used to ensure that multiple calls to #getBufferedComponentModel * return the same instance. * * @see #getBufferedComponentModel(String) */ private final Map bufferedComponentModels; // Instance Creation ****************************************************** /** * Constructs a PresentationModel where the initial bean is {@code null}.

* * Installs a default bean channel that checks the identity not equity * to ensure that listeners are unregistered properly if the old and * new bean are equal but not the same.

* * Installs a Trigger as initial trigger channel. * * @since 2.6.1 */ public PresentationModel() { this((B) null); } /** * Constructs a PresentationModel that adapts properties of the given bean.

* * Installs a default bean channel that checks the identity not equity * to ensure that listeners are unregistered properly if the old and * new bean are equal but not the same.

* * Installs a Trigger as initial trigger channel. * * @param bean the bean that holds the properties to adapt * @throws PropertyUnboundException if the {@code bean} does not * provide a pair of methods to register a PropertyChangeListener */ public PresentationModel(B bean) { this(new ValueHolder(bean, true)); } /** * Constructs a PresentationModel on the given bean using the given * trigger channel. The bean provides the properties to adapt.

* * Installs a default bean channel that checks the identity not equity * to ensure that listeners are unregistered properly if the old and * new bean are equal but not the same.

* * The trigger channel is shared by all buffered models that are created * using {@code #getBufferedModel}. * It can be replaced by any other Boolean ValueModel later. * Note that PresentationModel observes trigger value changes, * not value state. Therefore you must ensure that customer triggers * report value changes when asked to commit or flush. See the * Trigger implementation for an example. * * @param bean the bean that holds the properties to adapt * @param triggerChannel the ValueModel that triggers commit and flush events */ public PresentationModel( B bean, ValueModel triggerChannel) { this(new ValueHolder(bean, true), triggerChannel); } /** * Constructs a PresentationModel on the given bean channel. This channel * holds a bean that in turn holds the properties to adapt.

* * It is strongly recommended that the bean channel checks the identity * not equity. This ensures that listeners are unregistered properly if * the old and new bean are equal but not the same.

* * The trigger channel is initialized as a {@code Trigger}. * It may be replaced by any other Boolean ValueModel later. * Note that PresentationModel observes trigger value changes, * not value state. Therefore you must ensure that customer triggers * report value changes when asked to commit or flush. See the * Trigger implementation for an example. * * @param beanChannel the ValueModel that holds the bean * * @throws PropertyUnboundException if the {@code bean} does not * provide a pair of methods to register a PropertyChangeListener */ public PresentationModel(ValueModel beanChannel) { this(beanChannel, new Trigger()); } /** * Constructs a PresentationModel on the given bean channel using the given * trigger channel. The bean channel holds a bean that in turn holds * the properties to adapt.

* * It is strongly recommended that the bean channel checks the identity * not equity. This ensures that listeners are unregistered properly if * the old and new bean are equal but not the same.

* * The trigger channel is shared by all buffered * models that are created using {@code #buffer}. * It can be replaced by any other Boolean ValueModel later. * Note that PresentationModel observes trigger value changes, * not value state. Therefore you must ensure that customer triggers * report value changes when asked to commit or flush. See the * Trigger implementation for an example. * * @param beanChannel the ValueModel that holds the bean * @param triggerChannel the ValueModel that triggers commit and flush events */ public PresentationModel( ValueModel beanChannel, ValueModel triggerChannel) { this.beanAdapter = createBeanAdapter(beanChannel); this.triggerChannel = triggerChannel; this.wrappedBuffers = new HashMap(); this.componentModels = new HashMap(); this.bufferedComponentModels = new HashMap(); this.bufferingUpdateHandler = new BufferingStateHandler(); this.changed = false; this.changedUpdateHandler = new UpdateHandler(); beanAdapter.addPropertyChangeListener(new BeanChangeHandler()); // By default we observe changes in the bean. observeChanged(beanAdapter, BeanAdapter.PROPERTY_CHANGED); } /** * Creates and returns a BeanAdapter for the given bean channel. * For compatibility with the 1.0.x, 1.1.x, and 1.2.x series, * this default implementation creates a BeanAdapter that always observes * the bean. Subclasses may override to observe only observable beans.

* * Here's an example code for a custom implementation: *

     *  boolean observe =
     *        (beanChannel == null)
     *     || (beanChannel.getValue() == null)
     *     || BeanUtils.supportsBoundProperties((beanChannel.getValue().getClass());
     *  return new BeanAdapter(beanChannel, observe);
     *  

* * A future implementation shall return a BeanAdapter-like interface, * not a BeanAdapter. * * @param beanChannel the ValueModel that holds the bean * @return the created bean adapter * @since 1.3 */ protected BeanAdapter createBeanAdapter(ValueModel beanChannel) { return new BeanAdapter(beanChannel, true); } // Managing the Target Bean ********************************************** /** * Returns the ValueModel that holds the bean that in turn holds * the adapted properties. This bean channel is shared by the * PropertyAdapters created by the factory methods * {@code #getModel} and {@code #getBufferedModel}. * * @return the ValueModel that holds the bean that in turn * holds the adapted properties * * @see #getBean() * @see #setBean(Object) */ public ValueModel getBeanChannel() { return beanAdapter.getBeanChannel(); } /** * Returns the bean that holds the adapted properties. This bean * is the bean channel's content. * * @return the bean that holds the adapted properties * * @see #setBean(Object) * @see #getBeanChannel() */ public B getBean() { return (B) getBeanChannel().getValue(); } /** * Sets a new bean as content of the bean channel. * All adapted properties will reflect this change. * * @param newBean the new bean * * @see #getBean() * @see #getBeanChannel() */ public void setBean(B newBean) { getBeanChannel().setValue(newBean); } /** * The underlying BeanAdapter is about to change the bean. * Allows to perform operations before the bean change happens. * For example you can remove listeners that shall not be notified * if adapted properties change just because of the bean change. * Or you can reset values, set fields to {@code null} etc.

* * The default behavior fires a PropertyChangeEvent for property * {@code #PROPERTY_BEFORE_BEAN}. * Note: Subclasses that override this method * must invoke super or perform the same behavior.

* * This method is invoked by the BeanChangeHandler listening to the * beforeBean non-readable property of the BeanAdapter. * * @param oldBean the bean before the change * @param newBean the bean that will be adapted after the change * * @see #afterBeanChange(Object, Object) * @see #PROPERTY_BEFORE_BEAN * @see #PROPERTY_BEAN * @see #PROPERTY_AFTER_BEAN * @see BeanAdapter */ protected void beforeBeanChange(B oldBean, B newBean) { firePropertyChange(PROPERTY_BEFORE_BEAN, oldBean, newBean, true); } /** * The underlying BeanAdapter has changed the target bean. * Allows to perform operations after the bean changed. * For example you can re-add listeners that were removed in * {@code #beforeBeanChange}. Or you can reset values, * reset custom changed state, set fields to {@code null} etc.

* * The default behavior resets the change tracker's changed state * and fires a PropertyChangeEvent for the property * {@code #PROPERTY_AFTER_BEAN}. * Note: Subclasses that override this method * must invoke super or perform the same behavior.

* * This method is invoked by the BeanChangeHandler listening to the * afterBean non-readable property of the BeanAdapter. * * @param oldBean the bean that was adapted before the change * @param newBean the bean that is already the new target bean * * @see #beforeBeanChange(Object, Object) * @see #PROPERTY_BEFORE_BEAN * @see #PROPERTY_BEAN * @see #PROPERTY_AFTER_BEAN * @see BeanAdapter */ protected void afterBeanChange(B oldBean, B newBean) { setChanged(false); firePropertyChange(PROPERTY_AFTER_BEAN, oldBean, newBean, true); } /** * Allows to perform operations after the bean changed. * * @param oldBean the bean that was adapted before the change * @param newBean the bean that is already the new target bean */ protected void onBeanChanging(B oldBean, B newBean) { // Does nothing; subclasses may override. } /** * Allows to perform operations before the bean changes. * * @param oldBean the bean before the change * @param newBean the bean that will be adapted after the change */ protected void onBeanChanged(B oldBean, B newBean) { // Does nothing; subclasses may override. } // Accessing Property Values ********************************************** /** * Returns the value of specified bean property, {@code null} * if the current bean is {@code null}.

* * This operation is supported only for readable bean properties. * * @param propertyName the name of the property to be read * @return the value of the adapted bean property, null if the bean is null * * @throws NullPointerException if the property name is null * @throws UnsupportedOperationException if the property is write-only * @throws PropertyNotFoundException if the property could not be found * @throws PropertyAccessException if the value could not be read * * @since 1.1 */ public Object getValue(String propertyName) { return beanAdapter.getValue(propertyName); } /** * Sets the given new value for the specified bean property. Does nothing * if this adapter's bean is {@code null}. If the setter associated * with the propertyName throws a PropertyVetoException, it is silently * ignored.

* * Notifies the associated value change listeners if the bean reports * a property change. Note that a bean may suppress PropertyChangeEvents * if the old and new value are the same, or if the old and new value * are equal.

* * This operation is supported only for writable bean properties. * * @param propertyName the name of the property to set * @param newValue the value to set * * @throws NullPointerException if the property name is null * @throws UnsupportedOperationException if the property is read-only * @throws PropertyNotFoundException if the property could not be found * @throws PropertyAccessException if the new value could not be set * * @since 1.1 */ public void setValue(String propertyName, Object newValue) { beanAdapter.setValue(propertyName, newValue); } /** * Sets a new value for the specified bean property. Does nothing if the * bean is {@code null}. If the setter associated with the propertyName * throws a PropertyVetoException, this methods throws the same exception.

* * Notifies the associated value change listeners if the bean reports * a property change. Note that a bean may suppress PropertyChangeEvents * if the old and new value are the same, or if the old and new value * are equal.

* * This operation is supported only for writable bean properties. * * @param propertyName the name of the property to set * @param newValue the value to set * * @throws NullPointerException if the property name is null * @throws UnsupportedOperationException if the property is read-only * @throws PropertyNotFoundException if the property could not be found * @throws PropertyAccessException if the new value could not be set * @throws PropertyVetoException if the bean setter * throws a PropertyVetoException * * @since 1.1 */ public void setVetoableValue(String propertyName, Object newValue) throws PropertyVetoException { beanAdapter.setVetoableValue(propertyName, newValue); } /** * Returns the value of specified buffered bean property. * It is a shorthand for writing *

getBufferedModel(propertyName).getValue()
* As a side-effect, this method may create a buffered model. * * @param propertyName the name of the property to be read * @return the value of the adapted bean property, null if the bean is null * * @throws NullPointerException if the property name is null * @throws UnsupportedOperationException if the property is write-only * @throws PropertyNotFoundException if the property could not be found * @throws PropertyAccessException if the value could not be read * * @since 1.1 */ public Object getBufferedValue(String propertyName) { return getBufferedModel(propertyName).getValue(); } /** * Buffers the given value for the specified bean property. * It is a shorthand for writing *
getBufferedModel(propertyName).setValue(newValue)
* As a side-effect, this method may create a buffered model. * * @param propertyName the name of the property to set * @param newValue the value to set * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws PropertyAccessException if the new value could not be set * * @since 1.1 */ public void setBufferedValue(String propertyName, Object newValue) { getBufferedModel(propertyName).setValue(newValue); } // Factory Methods for Bound Models *************************************** /** * Looks up and lazily creates a ValueModel that adapts * the bound property with the specified name. Uses the * Bean introspection to look up the getter and setter names.

* * Subsequent calls to this method with the same property name * return the same ValueModel.

* * To prevent potential runtime errors it eagerly looks up * the associated PropertyDescriptor if the target bean is not null.

* * For each property name all calls to this method * and to {@code #getModel(String, String, String)} must use * the same getter and setter names. Attempts to violate this constraint * will be rejected with an IllegalArgumentException. Especially once * you've called this method you must not call * {@code #getModel(String, String, String)} with a non-null * getter or setter name. And vice versa, once you've called the latter * method with a non-null getter or setter name, you must not call * this method.

* * This method uses a return type of AbstractValueModel, not a ValueModel. * This makes the AbstractValueModel convenience type converters available, * which can significantly shrink the source code necessary to read and * write values from/to these models. * * @param propertyName the name of the property to adapt * @return a ValueModel that adapts the property with the specified name * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws IllegalArgumentException * if {@code #getModel(String, String, String)} has been * called before with the same property name and a non-null getter * or setter name * * @see AbstractValueModel * @see BeanAdapter * @see #getModel(String, String, String) * @see #getBufferedModel(String) */ public AbstractValueModel getModel(String propertyName) { return beanAdapter.getValueModel(propertyName); } /** * Looks up and lazily creates a ValueModel that adapts the bound property * with the given name. Unlike {@code #getModel(String)} * this method bypasses the Bean Introspection and uses the given getter * and setter names to setup the access to the adapted Bean property.

* * Subsequent calls to this method with the same parameters * will return the same ValueModel.

* * To prevent potential runtime errors this method eagerly looks up * the associated PropertyDescriptor if the target bean is not null.

* * For each property name all calls to this method * and to {@code #getModel(String)} must use the same * getter and setter names. Attempts to violate this constraint * will be rejected with an IllegalArgumentException. Especially * once you've called this method with a non-null getter or setter name, * you must not call {@code #getModel(String)}. And vice versa, * once you've called the latter method you must not call this method * with a non-null getter or setter name.

* * This method uses a return type of AbstractValueModel, not a ValueModel. * This makes the AbstractValueModel convenience type converters available, * which can significantly shrink the source code necessary to read and * write values from/to these models. * * @param propertyName the name of the property to adapt * @param getterName the name of the method that reads the value * @param setterName the name of the method that sets the value * @return a ValueModel that adapts the property with the specified name * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws IllegalArgumentException if this method has been called before * with the same property name and different getter or setter names * * @see AbstractValueModel * @see BeanAdapter * @see #getModel(String, String, String) * @see #getBufferedModel(String) */ public AbstractValueModel getModel(String propertyName, String getterName, String setterName) { return beanAdapter.getValueModel(propertyName, getterName, setterName); } /** * Looks up and lazily creates a ComponentValueModel that adapts * the bound property with the specified name. Uses the standard * Bean introspection to look up the getter and setter names.

* * Subsequent calls to this method with the same property name * return the same ComponentValueModel.

* * To prevent potential runtime errors it eagerly looks up * the associated PropertyDescriptor if the target bean is not null.

* * For each property name all calls to this method * and to {@code #getModel(String, String, String)} must use * the same getter and setter names. Attempts to violate this constraint * will be rejected with an IllegalArgumentException. Especially once * you've called this method you must not call * {@code #getModel(String, String, String)} with a non-null * getter or setter name. And vice versa, once you've called the latter * method with a non-null getter or setter name, you must not call * this method.

* * This returned ComponentValueModel provides convenience type converter * method from AbstractValueModel and allows to modify GUI state such as * enabled, visible, and editable in this presentation model. * This can significantly shrink the source code necessary to handle * GUI state changes. * * @param propertyName the name of the property to adapt * @return a ValueModel that adapts the property with the specified name * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws IllegalArgumentException * if {@code #getModel(String, String, String)} has been * called before with the same property name and a non-null getter * or setter name * * @see ComponentValueModel * @see AbstractValueModel * @see BeanAdapter * @see #getModel(String, String, String) * @see #getBufferedModel(String) * @see Bindings#addComponentPropertyHandler(JComponent, ValueModel) * * @since 1.1 */ @Override public AbstractWrappedValueModel getComponentModel(String propertyName) { AbstractWrappedValueModel componentModel = componentModels.get(propertyName); if (componentModel == null) { AbstractValueModel model = getModel(propertyName); componentModel = new DefaultComponentValueModel(model); componentModels.put(propertyName, componentModel); } return componentModel; } // Factory Methods for Buffered Models ************************************ /** * Looks up or creates a buffered adapter to the read-write property * with the given name on this PresentationModel's bean channel. Creates a * BufferedValueModel that wraps a ValueModel that adapts the bean property * with the specified name. The buffered model uses this PresentationModel's * trigger channel to listen for commit and flush events.

* * The created BufferedValueModel is stored in a Map. Hence * subsequent calls to this method with the same property name * return the same BufferedValueModel.

* * To prevent potential runtime errors this method eagerly looks up * the associated PropertyDescriptor if the target bean is not null.

* * For each property name all calls to this method * and to {@code #getBufferedModel(String, String, String)} must use * the same getter and setter names. Attempts to violate this constraint * will be rejected with an IllegalArgumentException. Especially once * you've called this method you must not call * {@code #getBufferedModel(String, String, String)} with a non-null * getter or setter name. And vice versa, once you've called the latter * method with a non-null getter or setter name, you must not call * this method. * * @param propertyName the name of the read-write property to adapt * @return a buffered adapter to the property with the given name * on this model's bean channel using this model's trigger channel * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws IllegalArgumentException * if {@code #getBufferedModel(String, String, String)} has been * called before with the same property name and a non-null getter * or setter name * * @see BufferedValueModel * @see ValueModel * @see Trigger * @see BeanAdapter * @see #getModel(String) * @see #getBufferedModel(String, String, String) */ public BufferedValueModel getBufferedModel(String propertyName) { return getBufferedModel(propertyName, null, null); } /** * Looks up or creates a buffered adapter to the read-write property * with the given name on this PresentationModel's bean channel using * the specified getter and setter name to read and write values. Creates * a {@code BufferedValueModel} that wraps a {@code ValueModel} * that adapts the bean property with the specified name. * The buffered model uses this PresentationModel's trigger channel * to listen for commit and flush events.

* * The created BufferedValueModel is stored in a Map so it can be * looked up if it is requested multiple times.

* * To prevent potential runtime errors this method eagerly looks up * the associated PropertyDescriptor if the target bean is not null.

* * For each property name all calls to this method * and to {@code #getBufferedModel(String)} must use the same * getter and setter names. Attempts to violate this constraint * will be rejected with an IllegalArgumentException. Especially * once you've called this method with a non-null getter or setter name, * you must not call {@code #getBufferedModel(String)}. And vice versa, * once you've called the latter method you must not call this method * with a non-null getter or setter name. * * @param propertyName the name of the property to adapt * @param getterName the name of the method that reads the value * @param setterName the name of the method that sets the value * @return a buffered adapter to the property with the given name * on this model's bean channel using this model's trigger channel * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws IllegalArgumentException if this method has been called before * with the same property name and different getter or setter names * * @see BufferedValueModel * @see ValueModel * @see Trigger * @see BeanAdapter * @see #getModel(String) * @see #getBufferedModel(String) */ public BufferedValueModel getBufferedModel(String propertyName, String getterName, String setterName) { WrappedBuffer wrappedBuffer = wrappedBuffers.get(propertyName); if (wrappedBuffer == null) { wrappedBuffer = new WrappedBuffer( buffer(getModel(propertyName, getterName, setterName)), getterName, setterName); wrappedBuffers.put(propertyName, wrappedBuffer); } else { checkArgument(Objects.equals(getterName, wrappedBuffer.getterName) && Objects.equals(setterName, wrappedBuffer.setterName), "You must not invoke this method twice " + "with different getter and/or setter names."); } return wrappedBuffer.buffer; } /** * Looks up or creates a buffered component adapter to the read-write * property with the given name on this PresentationModel's bean channel. * Creates a ComponentValueModel that wraps a BufferedValueModel that * in turn wraps a ValueModel that adapts the bean property with the * specified name. The buffered model uses this PresentationModel's * trigger channel to listen for commit and flush events. * The ComponentValueModel allows to set component state in this * presentation model.

* * The created ComponentValueModel is stored in a Map. Hence * subsequent calls to this method with the same property name * return the same ComponentValueModel.

* * To prevent potential runtime errors this method eagerly looks up * the associated PropertyDescriptor if the target bean is not null.

* * For each property name all calls to this method * and to {@code #getBufferedModel(String, String, String)} must use * the same getter and setter names. Attempts to violate this constraint * will be rejected with an IllegalArgumentException. Especially once * you've called this method you must not call * {@code #getBufferedModel(String, String, String)} with a non-null * getter or setter name. And vice versa, once you've called the latter * method with a non-null getter or setter name, you must not call * this method. * * @param propertyName the name of the read-write property to adapt * @return a ComponentValueModel that wraps a buffered adapter * to the property with the given name * on this model's bean channel using this model's trigger channel * * @throws NullPointerException if the property name is null * @throws PropertyNotFoundException if the property could not be found * @throws IllegalArgumentException * if {@code #getBufferedModel(String, String, String)} has been * called before with the same property name and a non-null getter * or setter name * * @see ComponentValueModel * @see BufferedValueModel * @see ValueModel * @see Trigger * @see BeanAdapter * @see #getModel(String) * @see #getBufferedModel(String) * @see #getComponentModel(String) * @see Bindings#addComponentPropertyHandler(JComponent, ValueModel) * * @since 1.1 */ public AbstractWrappedValueModel getBufferedComponentModel(String propertyName) { AbstractWrappedValueModel bufferedComponentModel = bufferedComponentModels.get(propertyName); if (bufferedComponentModel == null) { AbstractValueModel model = getBufferedModel(propertyName); bufferedComponentModel = new DefaultComponentValueModel(model); bufferedComponentModels.put(propertyName, bufferedComponentModel); } return bufferedComponentModel; } /** * Wraps the given ValueModel with a BufferedValueModel that * uses this model's trigger channel to trigger commit and flush events. * * @param valueModel the ValueModel to be buffered * @return a BufferedValueModel triggered by the model's trigger channel * * @see BufferedValueModel * @see ValueModel * @see Trigger * @see #getBufferedModel(String) */ private BufferedValueModel buffer(ValueModel valueModel) { BufferedValueModel bufferedModel = new BufferedValueModel( valueModel, getTriggerChannel()); bufferedModel.addPropertyChangeListener(BufferedValueModel.PROPERTY_BUFFERING, bufferingUpdateHandler); return bufferedModel; } // Accessing the Trigger Channel ****************************************** /** * Returns a ValueModel that can be shared and used to trigger commit * and flush events in BufferedValueModels. The trigger channel's value * changes to true in {@code #triggerCommit} and it changes to false * in {@code #triggerFlush}.

* * This trigger channel is used to commit and flush values * in the BufferedValueModels returned by {@code #getBufferedModel}. * * @return this model's trigger channel * * @see BufferedValueModel * @see ValueModel * @see #setTriggerChannel(ValueModel) */ public ValueModel getTriggerChannel() { return triggerChannel; } /** * Sets the given ValueModel as this model's new trigger channel. * Sets the new trigger channel in all existing BufferedValueModels * that have been created using {@code #getBufferedModel}. * Subsequent invocations of {@code #triggerCommit} and * {@code #triggerFlush} will trigger commit and flush events * using the new trigger channel. * * @param newTriggerChannel the ValueModel to be set as * this model's new trigger channel * @throws NullPointerException if the new trigger channel is {@code null} * * @see BufferedValueModel * @see ValueModel * @see #getTriggerChannel() */ public void setTriggerChannel(ValueModel newTriggerChannel) { checkNotNull(newTriggerChannel, "The trigger channel must not be null."); ValueModel oldTriggerChannel = getTriggerChannel(); triggerChannel = newTriggerChannel; for (WrappedBuffer wrappedBuffer : wrappedBuffers.values()) { wrappedBuffer.buffer.setTriggerChannel(triggerChannel); } firePropertyChange( PROPERTY_TRIGGERCHANNEL, oldTriggerChannel, newTriggerChannel); } /** * Sets the trigger channel to true which in turn triggers commit * events in all BufferedValueModels that share this trigger. * * @see #triggerFlush() */ public void triggerCommit() { if (Boolean.TRUE.equals(getTriggerChannel().getValue())) { getTriggerChannel().setValue(null); } getTriggerChannel().setValue(Boolean.TRUE); } /** * Sets the trigger channel to false which in turn triggers flush * events in all BufferedValueModels that share this trigger. * * @see #triggerCommit() */ public void triggerFlush() { if (Boolean.FALSE.equals(getTriggerChannel().getValue())) { getTriggerChannel().setValue(null); } getTriggerChannel().setValue(Boolean.FALSE); } // Managing the Buffering State ******************************************* /** * Answers whether any of the buffered models is buffering. * Useful to enable and disable UI actions and operations * that depend on the buffering state. * * @return true if any of the buffered models is buffering, * false, if all buffered models write-through */ public boolean isBuffering() { return buffering; } /** * Sets the buffering state to the specified value. * * @param newValue the new buffering state */ private void setBuffering(boolean newValue) { boolean oldValue = isBuffering(); buffering = newValue; firePropertyChange(PROPERTY_BUFFERING, oldValue, newValue); } private void updateBufferingState(boolean latestBufferingStateChange) { if (buffering == latestBufferingStateChange) { return; } boolean nowBuffering = false; for (WrappedBuffer wrappedBuffer : wrappedBuffers.values()) { BufferedValueModel model = wrappedBuffer.buffer; nowBuffering = nowBuffering || model.isBuffering(); if (!buffering && nowBuffering) { setBuffering(true); return; } } setBuffering(nowBuffering); } // Changed State ********************************************************* /** * Answers whether one of the registered ValueModels has changed * since the changed state has been reset last time.

* * Note: Unlike {@code #resetChanged} this method * is not intended to be overridden by subclasses. * If you want to track changes of other ValueModels, bean properties, or * of submodels, register them by means of {@code #observeChanged}. * Overriding {@code #isChanged} to include the changed state * of submodels would return the correct changed value, but it would bypass * the change notification from submodels to this model. * Therefore submodels must be observed, which can be achieve using * {@code #observeChanged}.

* * To reset the changed state invoke {@code #resetChanged}. * In case you track the changed state of submodels override * {@code #resetChanged} to reset the changed state in these * submodels too. * * @return true if an observed property has changed since the last reset * * @see #observeChanged(ValueModel) * @see #observeChanged(Object, String) * @see #resetChanged() */ public boolean isChanged() { return changed; } /** * Resets this model's changed state to {@code false}. * Therefore it resets the changed states of the change tracker * and the underlying bean adapter.

* * Subclasses may override this method to reset the changed state * of submodels. The overriding method must invoke this super behavior. * For example if you have a MainModel that is composed of * two submodels Submodel1 and Submodel2, you may write: *

     * public void resetChanged() {
     *     super.resetChanged();
     *     getSubmodel1().resetChanged();
     *     getSubmodel2().resetChanged();
     * }
     * 
* * @see #isChanged() * @see #observeChanged(ValueModel) * @see #observeChanged(Object, String) */ public void resetChanged() { setChanged(false); beanAdapter.resetChanged(); } protected void setChanged(boolean newValue) { boolean oldValue = isChanged(); changed = newValue; firePropertyChange(PROPERTY_CHANGED, oldValue, newValue); } // Observing Changes in ValueModel and Bean Properties ******************* /** * Observes the specified readable bound bean property in the given bean. * * @param bean the bean to be observed * @param propertyName the name of the readable bound bean property * @throws NullPointerException if the bean or propertyName is null * @throws PropertyNotBindableException if this class can't add * the PropertyChangeListener from the bean * * @see #retractInterestFor(Object, String) * @see #observeChanged(ValueModel) */ public void observeChanged(Object bean, String propertyName) { checkNotNull(bean, "The bean must not be null."); checkNotNull(propertyName, "The property name must not be null."); BeanUtils.addPropertyChangeListener(bean, propertyName, changedUpdateHandler); } /** * Observes value changes in the given ValueModel. * * @param valueModel the ValueModel to observe * @throws NullPointerException if the valueModel is null * * @see #retractInterestFor(ValueModel) * @see #observeChanged(Object, String) */ public void observeChanged(ValueModel valueModel) { checkNotNull(valueModel, "The ValueModel must not be null."); valueModel.addValueChangeListener(changedUpdateHandler); } /** * Retracts interest for the specified readable bound bean property * in the given bean. * * @param bean the bean to be observed * @param propertyName the name of the readable bound bean property * @throws NullPointerException if the bean or propertyName is null * @throws PropertyNotBindableException if this class can't remove * the PropertyChangeListener from the bean * * @see #observeChanged(Object, String) * @see #retractInterestFor(ValueModel) */ public void retractInterestFor(Object bean, String propertyName) { checkNotNull(bean, "The bean must not be null."); checkNotNull(propertyName, "The property name must not be null."); BeanUtils.removePropertyChangeListener(bean, propertyName, changedUpdateHandler); } /** * Retracts interest for value changes in the given ValueModel. * * @param valueModel the ValueModel to observe * @throws NullPointerException if the valueModel is null * * @see #observeChanged(ValueModel) * @see #retractInterestFor(Object, String) */ public void retractInterestFor(ValueModel valueModel) { checkNotNull(valueModel, "The ValueModel must not be null."); valueModel.removeValueChangeListener(changedUpdateHandler); } // Managing Bean Property Change Listeners ******************************* /** * Adds a PropertyChangeListener to the list of bean listeners. The * listener is registered for all bound properties of the target bean.

* * The listener will be notified if and only if this BeanAdapter's current * bean changes a property. It'll not be notified if the bean changes.

* * If listener is {@code null}, no exception is thrown and * no action is performed. * * @param listener the PropertyChangeListener to be added * * @see #removeBeanPropertyChangeListener(PropertyChangeListener) * @see #removeBeanPropertyChangeListener(String, PropertyChangeListener) * @see #addBeanPropertyChangeListener(String, PropertyChangeListener) * @see #getBeanPropertyChangeListeners() */ public synchronized void addBeanPropertyChangeListener( PropertyChangeListener listener) { beanAdapter.addBeanPropertyChangeListener(listener); } /** * Removes a PropertyChangeListener from the list of bean listeners. * This method should be used to remove PropertyChangeListeners that * were registered for all bound properties of the target bean.

* * If listener is {@code null}, no exception is thrown and * no action is performed. * * @param listener the PropertyChangeListener to be removed * * @see #addBeanPropertyChangeListener(PropertyChangeListener) * @see #addBeanPropertyChangeListener(String, PropertyChangeListener) * @see #removeBeanPropertyChangeListener(String, PropertyChangeListener) * @see #getBeanPropertyChangeListeners() */ public synchronized void removeBeanPropertyChangeListener( PropertyChangeListener listener) { beanAdapter.removeBeanPropertyChangeListener(listener); } /** * Adds a PropertyChangeListener to the list of bean listeners for a * specific property. The specified property may be user-defined.

* * The listener will be notified if and only if this BeanAdapter's * current bean changes the specified property. It'll not be notified * if the bean changes. If you want to observe property changes and * bean changes, you may observe the ValueModel that adapts this property * - as returned by {@code #getModel(String)}.

* * Note that if the bean is inheriting a bound property, then no event * will be fired in response to a change in the inherited property.

* * If listener is {@code null}, no exception is thrown and * no action is performed. * * @param propertyName one of the property names listed above * @param listener the PropertyChangeListener to be added * * @see #removeBeanPropertyChangeListener(String, PropertyChangeListener) * @see #addBeanPropertyChangeListener(String, PropertyChangeListener) * @see #getBeanPropertyChangeListeners(String) */ public synchronized void addBeanPropertyChangeListener( String propertyName, PropertyChangeListener listener) { beanAdapter.addBeanPropertyChangeListener(propertyName, listener); } /** * Removes a PropertyChangeListener from the listener list for a specific * property. This method should be used to remove PropertyChangeListeners * that were registered for a specific bound property.

* * If listener is {@code null}, no exception is thrown and * no action is performed. * * @param propertyName a valid property name * @param listener the PropertyChangeListener to be removed * * @see #addBeanPropertyChangeListener(String, PropertyChangeListener) * @see #removeBeanPropertyChangeListener(PropertyChangeListener) * @see #getBeanPropertyChangeListeners(String) */ public synchronized void removeBeanPropertyChangeListener( String propertyName, PropertyChangeListener listener) { beanAdapter.removeBeanPropertyChangeListener(propertyName, listener); } // Requesting Listener Sets *********************************************** /** * Returns an array of all the property change listeners * registered on this component. * * @return all of this component's {@code PropertyChangeListener}s * or an empty array if no property change * listeners are currently registered * * @see #addBeanPropertyChangeListener(PropertyChangeListener) * @see #removeBeanPropertyChangeListener(PropertyChangeListener) * @see #getBeanPropertyChangeListeners(String) * @see java.beans.PropertyChangeSupport#getPropertyChangeListeners() */ public synchronized PropertyChangeListener[] getBeanPropertyChangeListeners() { return beanAdapter.getBeanPropertyChangeListeners(); } /** * Returns an array of all the listeners which have been associated * with the named property. * * @param propertyName the name of the property to lookup listeners * @return all of the {@code PropertyChangeListeners} associated with * the named property or an empty array if no listeners have * been added * * @see #addBeanPropertyChangeListener(String, PropertyChangeListener) * @see #removeBeanPropertyChangeListener(String, PropertyChangeListener) * @see #getBeanPropertyChangeListeners() */ public synchronized PropertyChangeListener[] getBeanPropertyChangeListeners(String propertyName) { return beanAdapter.getBeanPropertyChangeListeners(propertyName); } // Misc ******************************************************************* /** * Removes the PropertyChangeHandler from the observed bean, * if the bean is not {@code null}. * Also removes all listeners from the bean that have been registered * with {@code #addBeanPropertyChangeListener} before.

* * PresentationModels have a PropertyChangeListener registered with * the target bean. Hence, a bean has a reference to all PresentationModels * that hold it as bean. To avoid memory leaks it is recommended to remove * this listener, if the bean lives much longer than the PresentationModel, * enabling the garbage collector to remove the PresentationModel. * To do so, you can call {@code setBean(null)} or set the * bean channel's value to null. * As an alternative you can use event listener lists in your beans * that implement references with {@code WeakReference}.

* * Setting the bean to null has side-effects, for example the model * fires a change event for the bound property bean and * other properties. * And the value of ValueModel's vent by this model may change. * However, typically this is fine and setting the bean to null * is the first choice for removing the reference from the bean to * the PresentationModel. * Another way to clear the reference from the target bean is to call * this {@code #release} method; it has no side-effects.

* * Since version 2.0.4 it is safe to call this method multiple times, * however, the PresentationModel must not be used anymore once #release * has been called. * * @see #setBean(Object) * @see java.lang.ref.WeakReference * * @since 1.2 */ public void release() { beanAdapter.release(); } // Helper Class *********************************************************** /** * Holds a BufferedValueModel together with the names of the getter * and setter. Used to look up models in {@code #getBufferedModel}. * Also ensures that there are no two buffered models with different * getter/setter pairs. * * @see PresentationModel#getBufferedModel(String) * @see PresentationModel#getBufferedModel(String, String, String) */ private static final class WrappedBuffer { final BufferedValueModel buffer; final String getterName; final String setterName; WrappedBuffer( BufferedValueModel buffer, String getterName, String setterName) { this.buffer = buffer; this.getterName = getterName; this.setterName = setterName; } } // Event Handling and Forwarding Changes ********************************** /** * Listens to changes of the bean, invoked the before and after methods, * and forwards the bean change events. */ private final class BeanChangeHandler implements PropertyChangeListener { /** * The target bean will change, changes, or has changed. * * @param evt the property change event to be handled */ @Override public void propertyChange(PropertyChangeEvent evt) { B oldBean = (B) evt.getOldValue(); B newBean = (B) evt.getNewValue(); String propertyName = evt.getPropertyName(); if (BeanAdapter.PROPERTY_BEFORE_BEAN.equals(propertyName)) { onBeanChanging(oldBean, newBean); beforeBeanChange(oldBean, newBean); } else if (BeanAdapter.PROPERTY_BEAN.equals(propertyName)) { firePropertyChange(PROPERTY_BEAN, oldBean, newBean, true); } else if (BeanAdapter.PROPERTY_AFTER_BEAN.equals(propertyName)) { afterBeanChange(oldBean, newBean); onBeanChanged(oldBean, newBean); } } } /** * Updates the buffering state if a model buffering state changed. */ private final class BufferingStateHandler implements PropertyChangeListener { /** * A registered BufferedValueModel has reported a change in its * buffering state. Update this model's buffering state. * * @param evt describes the property change */ @Override public void propertyChange(PropertyChangeEvent evt) { updateBufferingState(((Boolean) evt.getNewValue()).booleanValue()); } } /** * Listens to model changes and updates the changed state. */ private final class UpdateHandler implements PropertyChangeListener { /** * A registered bean property or ValueModel has changed. * Updates the changed state. If the property that changed is * 'changed' we assume that this is another changed state and * forward only changes to true. For all other property names, * we just update our changed state to true. * * @param evt the event that describes the property change */ @Override public void propertyChange(PropertyChangeEvent evt) { String propertyName = evt.getPropertyName(); if (!PROPERTY_CHANGED.equals(propertyName) || ((Boolean) evt.getNewValue()).booleanValue()) { setChanged(true); } } } }