/*
* 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.view.facelets.tag.jsf;
import java.io.IOException;
import javax.el.ValueExpression;
import javax.faces.component.UIComponent;
import javax.faces.component.ValueHolder;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.view.ValueHolderAttachedObjectHandler;
import javax.faces.view.facelets.ComponentHandler;
import javax.faces.view.facelets.ConverterHandler;
import javax.faces.view.facelets.FaceletContext;
import javax.faces.view.facelets.MetaRuleset;
import javax.faces.view.facelets.TagAttribute;
import javax.faces.view.facelets.TagException;
import javax.faces.view.facelets.TagHandlerDelegate;
import org.apache.myfaces.view.facelets.FaceletCompositionContext;
import org.apache.myfaces.view.facelets.tag.MetaRulesetImpl;
/**
* Handles setting a Converter instance on a ValueHolder. Will wire all attributes set to the Converter instance
* created/fetched. Uses the "binding" attribute for grabbing instances to apply attributes to. <p/> Will only
* set/create Converter is the passed UIComponent's parent is null, signifying that it wasn't restored from an existing
* tree.
*
* @author Leonardo Uribe (latest modification by $Author: lu4242 $)
* @version $Revision: 964310 $ $Date: 2010-07-15 01:17:19 -0500 (Thu, 15 Jul 2010) $
*
* @since 2.0
*/
public class ConverterTagHandlerDelegate extends TagHandlerDelegate implements ValueHolderAttachedObjectHandler
{
private ConverterHandler _delegate;
public ConverterTagHandlerDelegate(ConverterHandler delegate)
{
_delegate = delegate;
}
/**
* Set Converter instance on parent ValueHolder if it's not being restored.
* <ol>
* <li>Cast to ValueHolder</li>
* <li>If "binding" attribute was specified, fetch/create and re-bind to expression.</li>
* <li>Otherwise, call {@link #createConverter(FaceletContext) createConverter}.</li>
* <li>Call {@link ObjectHandler#setAttributes(FaceletContext, Object) setAttributes} on Converter instance.</li>
* <li>Set the Converter on the ValueHolder</li>
* <li>If the ValueHolder has a localValue, convert it and set the value</li>
* </ol>
*
* @see ValueHolder
* @see Converter
* @see #createConverter(FaceletContext)
* @see javax.faces.view.facelets.FaceletHandler#apply(javax.faces.view.facelets.FaceletContext, javax.faces.component.UIComponent)
*/
@Override
public void apply(FaceletContext ctx, UIComponent parent) throws IOException
{
// only process if it's been created
if (!ComponentHandler.isNew(parent))
{
return;
}
if (parent instanceof ValueHolder)
{
applyAttachedObject(ctx.getFacesContext(), parent);
}
else if (UIComponent.isCompositeComponent(parent))
{
if (getFor() == null)
{
throw new TagException(_delegate.getTag(), "is nested inside a composite component"
+ " but does not have a for attribute.");
}
FaceletCompositionContext mctx = FaceletCompositionContext.getCurrentInstance(ctx);
mctx.addAttachedObjectHandler(parent, _delegate);
}
else
{
throw new TagException(_delegate.getTag(), "Parent not composite component or an instance of ValueHolder: " + parent);
}
}
/**
* Create a Converter instance
*
* @param ctx
* FaceletContext to use
* @return Converter instance, cannot be null
*/
protected Converter createConverter(FaceletContext ctx)
{
if (_delegate.getConverterId(ctx) == null)
{
throw new TagException(
_delegate.getTag(),
"Default behavior invoked of requiring a converter-id passed in the constructor, must override ConvertHandler(ConverterConfig)");
}
return ctx.getFacesContext().getApplication().createConverter(_delegate.getConverterId(ctx));
}
@Override
public MetaRuleset createMetaRuleset(Class type)
{
return new MetaRulesetImpl(_delegate.getTag(), type).ignore("binding");
}
public void applyAttachedObject(FacesContext context, UIComponent parent)
{
// Retrieve the current FaceletContext from FacesContext object
FaceletContext faceletContext = (FaceletContext) context.getAttributes().get(
FaceletContext.FACELET_CONTEXT_KEY);
// cast to a ValueHolder
ValueHolder vh = (ValueHolder) parent;
ValueExpression ve = null;
Converter c = null;
if (_delegate.getBinding() != null)
{
ve = _delegate.getBinding().getValueExpression(faceletContext, Converter.class);
c = (Converter) ve.getValue(faceletContext);
}
if (c == null)
{
c = this.createConverter(faceletContext);
if (ve != null)
{
ve.setValue(faceletContext, c);
}
}
if (c == null)
{
throw new TagException(_delegate.getTag(), "No Converter was created");
}
_delegate.setAttributes(faceletContext, c);
vh.setConverter(c);
Object lv = vh.getLocalValue();
FacesContext faces = faceletContext.getFacesContext();
if (lv instanceof String)
{
vh.setValue(c.getAsObject(faces, parent, (String) lv));
}
}
public String getFor()
{
TagAttribute forAttribute = _delegate.getTagAttribute("for");
if (forAttribute == null)
{
return null;
}
else
{
return forAttribute.getValue();
}
}
}