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JSF components and utilities that can be used with any JSF implementation.
This library is based on the JSF1.1 version of Tomahawk, but with minor source code and build
changes to take advantage of JSF2.1 features. A JSF2.1 implementation is required to use this
version of the Tomahawk library.
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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.myfaces.custom.aliasbean;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.el.ValueExpression;
import javax.faces.FacesException;
import javax.faces.component.ContextCallback;
import javax.faces.component.UIComponent;
import javax.faces.component.UIComponentBase;
import javax.faces.component.visit.VisitCallback;
import javax.faces.component.visit.VisitContext;
import javax.faces.context.FacesContext;
import javax.faces.event.AbortProcessingException;
import javax.faces.event.FacesEvent;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFComponent;
import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFJspProperties;
import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFJspProperty;
import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFProperty;
import org.apache.myfaces.shared_tomahawk.component.BindingAware;
import org.apache.myfaces.shared_tomahawk.util.RestoreStateUtils;
/**
* The aliasBean tag allows you to create a temporary name for a real bean.
* The temporary name exists (is visible) only to the children of the aliasBean.
*
* One use of this feature is to pass "parameters" from an including page to an
* included one. The included page can use any name it desires for beans it needs to
* reference, and the including page can then use aliasBean to make those names
* refer to the beans it wishes to "pass" as parameters.
*
*
* Suppose you have a block of components you use often but with different beans. You
* can create a separate JSP page (or equivalent) containing these beans, where the
* value-bindings refer to some fictive bean name. Document these names as the required
* "parameters" for this JSP page. Wherever you wish to use this block you then declare
* an alias component mapping each of these "parameters" to whatever beans (or literal
* values) you really want to apply the block to, then use jsp:include (or equivalent)
* to include the reusable block of components.
*
*
* Note, however, that AliasBean does not work for component bindings; JSF1.1
* just has no mechanism available to set up the alias during the "restore view"
* phase while the bindings of its children are being re-established, and then
* remove the alias after the child bindings are done.
*
*
* As a special case, if this component's direct parent is an AliasBeansScope
* then the alias (temporary name) is active until the end of the parent
* component, rather than the end of this component.
*
*
* @author Sylvain Vieujot (latest modification by $Author: lu4242 $)
* @version $Revision: 690079 $ $Date: 2008-08-28 21:58:51 -0500 (jue, 28 ago 2008) $
*/
@JSFComponent(
name="t:aliasBean",
tagClass = "org.apache.myfaces.custom.aliasbean.AliasBeanTag",
tagHandler = "org.apache.myfaces.custom.aliasbean.AliasBeanTagHandler")
@JSFJspProperties(properties={
@JSFJspProperty(
name = "rendered",
returnType = "boolean",
tagExcluded = true),
@JSFJspProperty(
name = "binding",
returnType = "java.lang.String",
tagExcluded = true)
})
public class AliasBean extends UIComponentBase implements BindingAware
{
private static final Log log = LogFactory.getLog(AliasBean.class);
public static final String COMPONENT_TYPE = "org.apache.myfaces.AliasBean";
public static final String COMPONENT_FAMILY = "javax.faces.Data";
private Alias alias;
// Indicates whether withinScope has been initialised or not.
private boolean scopeSearched = false;
// True if this is a direct child of an AliasBeansScope component.
private boolean withinScope;
private transient FacesContext _context = null;
public AliasBean()
{
alias = new Alias(this);
}
public String getFamily()
{
return COMPONENT_FAMILY;
}
public String getRendererType() {
return null;
}
/**
* Define the "fictive" name which will be visible to the children
* of this component as an alias to the "real" object specified
* by the value attribute of this component.
*
* @param aliasBeanExpression
*/
@JSFProperty
public void setAlias(String aliasBeanExpression)
{
alias.setAliasBeanExpression(aliasBeanExpression);
}
/**
* The existing value that the alias can be set to. This can be
* a literal string (like "toto") or a reference to an existing
* bean (like "#{myBean.member1}").
*
*/
@JSFProperty(deferredValueType="java.lang.Object")
public String getValue()
{
String valueExpression = alias.getValueExpression();
if (valueExpression != null)
return valueExpression;
// Normally, this component will have no value, because the setValue method always
// passes that data on to the alias instead. However it is possible for someone
// to use f:attribute (or other mechanism?) to set the value instead. So when the
// alias has no value, look for it there.
ValueExpression vb = getValueExpression("value");
return vb != null ? (String) vb.getValue(getFacesContext().getELContext()) : null;
}
public void setValue(String valueExpression)
{
alias.setValueExpression(valueExpression);
}
public Object saveState(FacesContext context)
{
log.debug("saveState");
_context = context;
return new Object[]{super.saveState(context), alias.saveState()};
}
public void restoreState(FacesContext context, Object state)
{
log.debug("restoreState");
_context = context;
Object values[] = (Object[]) state;
super.restoreState(context, values[0]);
alias.restoreState(values[1]);
}
public Object processSaveState(FacesContext context)
{
if (context == null)
throw new NullPointerException("context");
if (isTransient())
return null;
makeAlias(context);
Map facetMap = null;
for (Iterator it = getFacets().entrySet().iterator(); it.hasNext();)
{
Map.Entry entry = (Map.Entry) it.next();
if (facetMap == null)
facetMap = new HashMap();
UIComponent component = (UIComponent) entry.getValue();
if (!component.isTransient())
{
facetMap.put(entry.getKey(), component.processSaveState(context));
}
}
List childrenList = null;
if (getChildCount() > 0)
{
for (Iterator it = getChildren().iterator(); it.hasNext();)
{
UIComponent child = (UIComponent) it.next();
if (!child.isTransient())
{
if (childrenList == null)
childrenList = new ArrayList(getChildCount());
childrenList.add(child.processSaveState(context));
}
}
}
removeAlias(context);
return new Object[]{saveState(context), facetMap, childrenList};
}
public void processRestoreState(FacesContext context, Object state)
{
if (context == null)
throw new NullPointerException("context");
Object myState = ((Object[]) state)[0];
restoreState(context, myState);
makeAlias(context);
Map facetMap = (Map) ((Object[]) state)[1];
List childrenList = (List) ((Object[]) state)[2];
for (Iterator it = getFacets().entrySet().iterator(); it.hasNext();)
{
Map.Entry entry = (Map.Entry) it.next();
Object facetState = facetMap.get(entry.getKey());
if (facetState != null)
{
((UIComponent) entry.getValue()).processRestoreState(context, facetState);
}
else
{
context.getExternalContext().log("No state found to restore facet " + entry.getKey());
}
}
if (getChildCount() > 0)
{
int idx = 0;
for (Iterator it = getChildren().iterator(); it.hasNext();)
{
UIComponent child = (UIComponent) it.next();
Object childState = childrenList.get(idx++);
if (childState != null)
{
child.processRestoreState(context, childState);
}
else
{
context.getExternalContext().log("No state found to restore child of component " + getId());
}
}
}
removeAlias(context);
}
public void processValidators(FacesContext context)
{
if (withinScope)
return;
log.debug("processValidators");
makeAlias(context);
super.processValidators(context);
removeAlias(context);
}
public void processDecodes(FacesContext context)
{
log.debug("processDecodes");
if (withinScope)
{
if (! alias.isActive())
makeAlias(context);
super.processDecodes(context);
return;
}
makeAlias(context);
super.processDecodes(context);
removeAlias(context);
}
public void processUpdates(FacesContext context)
{
if (withinScope)
return;
log.debug("processUpdates");
makeAlias(context);
super.processUpdates(context);
removeAlias(context);
}
public void encodeBegin(FacesContext context) throws IOException {
makeAlias(context);
}
public void encodeEnd(FacesContext context) throws IOException {
removeAlias();
}
public void queueEvent(FacesEvent event)
{
super.queueEvent(new FacesEventWrapper(event, this));
}
public void broadcast(FacesEvent event) throws AbortProcessingException
{
makeAlias();
if (event instanceof FacesEventWrapper)
{
FacesEvent originalEvent = ((FacesEventWrapper) event).getWrappedFacesEvent();
originalEvent.getComponent().broadcast(originalEvent);
}
else
{
super.broadcast(event);
}
removeAlias();
}
void makeAlias(FacesContext context)
{
_context = context;
makeAlias();
}
private void makeAlias()
{
if (! scopeSearched)
{
withinScope = getParent() instanceof AliasBeansScope;
if (withinScope)
{
AliasBeansScope aliasScope = (AliasBeansScope) getParent();
aliasScope.addAlias(alias);
}
scopeSearched = true;
}
alias.make(_context);
}
void removeAlias(FacesContext context)
{
_context = context;
removeAlias();
}
private void removeAlias()
{
if (! withinScope)
alias.remove(_context);
}
@Deprecated
public void handleBindings()
{
makeAlias(getFacesContext());
RestoreStateUtils.recursivelyHandleComponentReferencesAndSetValid(getFacesContext(),this,true);
removeAlias(getFacesContext());
}
@Override
public boolean invokeOnComponent(FacesContext context, String clientId,
ContextCallback callback) throws FacesException
{
makeAlias(getFacesContext());
try
{
return super.invokeOnComponent(context, clientId, callback);
}
finally
{
removeAlias(getFacesContext());
}
}
@Override
public boolean visitTree(VisitContext context, VisitCallback callback)
{
makeAlias(getFacesContext());
try
{
return super.visitTree(context, callback);
}
finally
{
removeAlias(getFacesContext());
}
}
}