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Public API for the Apache MyFaces Trinidad project
/*
* 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.trinidad.render;
import java.io.IOException;
import java.util.List;
import javax.faces.component.NamingContainer;
import javax.faces.component.UIComponent;
import javax.faces.component.UIForm;
import javax.faces.context.FacesContext;
import javax.faces.render.Renderer;
import org.apache.myfaces.trinidad.component.UIXForm;
import org.apache.myfaces.trinidad.logging.TrinidadLogger;
import org.apache.myfaces.trinidad.util.ComponentUtils;
/**
* Generic utilities for rendering.
*
*/
public class RenderUtils
{
private RenderUtils()
{
}
/**
* Encodes a component and all of its children.
*/
@SuppressWarnings("unchecked")
static public void encodeRecursive(FacesContext context,
UIComponent component)
throws IOException
{
if (component.isRendered())
{
component.encodeBegin(context);
if (component.getRendersChildren())
{
component.encodeChildren(context);
}
else
{
if (component.getChildCount() > 0)
{
for(UIComponent child : (List)component.getChildren())
{
encodeRecursive(context, child);
}
}
}
component.encodeEnd(context);
}
}
/**
* Retrieves id of the form the component is contained in.
*
* @param context the faces context object
* @param component UIComponent whose container form id is to be retuirned
*
* @return String id of the form if one exists in component's hierarchy,
* otherwise null
*/
public static String getFormId(
FacesContext context,
UIComponent component)
{
UIComponent form = null;
while (component != null)
{
if ((component instanceof UIForm) ||
(component instanceof UIXForm))
{
form = component;
break;
}
component = component.getParent();
}
if (form == null)
return null;
return form.getClientId(context);
}
/**
* Given a 'from' component and a relativeId,
* return the clientId for use at rendering time that will identify the
* id of the component you are referencing on the client.
* This is used for attributes like e.g. "for" and "chooseId".
*
*
* e.g., given this hierarchy
*
* <f:subview id="aaa">
* <f:subview id="xxx">
<tr:chooseColor id="cp1" .../>
<f:subview id="yyy">
<tr:inputColor id="sic1" chooseId="::cp1" .../>
</f:subview>
</f:subview>
</f:subview>
* The 'from' component is the inputColor component.
* The 'relativeId' is "::cp1". ('::' pops up one naming container)
* The return value is 'aaa:xxx:cp1' when
* the clientId of the 'xxx' component is 'aaa:xxx'.
*
*
*
* It does not assume that the target component can be located, although it does
* check. If it can't be found, it returns the correct relativeId anyway.
*
*
* A relativeId starting with
* NamingContainer.SEPARATOR_CHAR (that is, ':') will be
* treated as absolute (after dropping that character).
* A relativeId with no colons means it is within the same naming container
* as the 'from' component (this is within the 'from' component if 'from'
* is a naming container).
* A relativeId starting with '::' pops out of the 'from' component's
* naming container. If the 'from' component is a naming container, then
* '::' will pop out of the 'from' component itself. A relativeId with ':::' pops up two naming containers, etc.
* ComponentUtils.findRelativeComponent finds and returns the component, whereas
* this method returns a relativeId that can be used during renderering
* so the component can be found in javascript on the client.
*
* @param context
* @param from the component to search relative to
* @param scopedId the relative id path from the 'from' component to the
* component to find
* @return the clientId for the 'relative' component.
* @see ComponentUtils#findRelativeComponent
* @see javax.faces.component.UIComponent#findComponent
*/
public static String getRelativeId(
FacesContext context,
UIComponent from,
String scopedId)
{
if (from == null)
return null;
if ((scopedId == null) || (scopedId.length() == 0))
return null;
// Figure out how many colons
int colonCount = _getColonCount(scopedId);
// colonCount == 0: fully relative
// colonCount == 1: absolute
// colonCount > 1: for each extra colon after 1, pop out of
// the naming container (to the view root, if naming containers run out)
if (colonCount == 1)
return scopedId.substring(1);
if (colonCount == 0 && !(from instanceof NamingContainer))
{
// we do it the fast way if there
// are no colons and the from isn't a NamingContainer.
// the reason is this use case hasn't changed between the previous
// logic and the current logic for finding the component, so it
// is already backward compatible, and therefore we don't have to
// call the findComponent code for backward compatibility.
return _getRelativeId(context, from, scopedId, colonCount);
}
//
// We need to make it backward compatible, and
// the only way is to use the findRelativeComponent code.
// This way we'll have a hint that the syntax is 'old' if
// it can't be found. Plus, findRelativeComponent code has
// backward compatibilty built in.
UIComponent component =
ComponentUtils.findRelativeComponent(from, scopedId);
if (component == null && from instanceof NamingContainer)
{
component = ComponentUtils.findRelativeComponent(from.getParent(), scopedId);
if (component != null)
{
_LOG.warning("DEPRECATED_RELATIVE_ID_SYNTAX",
new Object[] {scopedId, from});
}
}
// the component wasn't found, but go ahead and return something smart
if (component == null)
{
return _getRelativeId(context, from, scopedId, colonCount);
}
else
{
return component.getClientId(context);
}
}
/**
* Returns the clientId used by the renderer in place of the clientId used by the component.
* Certain renderers render their root element with a clientId that differs from the one
* used by the component.
* @param context FacesContent.
* @param component UIComponent.
* @return component clientId if the renderer clientId is null. Otherwise clientId used by
* renderer.
*/
public static String getRendererClientId(
FacesContext context,
UIComponent component)
{
String clientId = component.getClientId(context);
String family = component.getFamily();
String rendererType = component.getRendererType();
if (rendererType != null)
{
Renderer renderer = context.getRenderKit().getRenderer(family, rendererType);
if (renderer instanceof CoreRenderer)
{
CoreRenderer coreRenderer = (CoreRenderer) renderer;
String rendererClientId = coreRenderer.getClientId(context, component);
return rendererClientId == null ? clientId : rendererClientId;
}
}
return clientId;
}
// This does NOT use findComponent
// ComponentUtils.findRelativeComponent finds the component, whereas
// this method returns a relativeId that can be used during renderering
// so the component can be found in javascript on the client.
// This code is faster because it doesn't have to find the component.
// It is used when the getRelativeId's findRelativeComponent cannot find
// the component. This way we can return the relativeId anyway.
private static String _getRelativeId(
FacesContext context,
UIComponent from,
String relativeId,
int colonCount)
{
if (colonCount == 1)
return relativeId.substring(1);
else if (colonCount > 1)
{
relativeId = relativeId.substring(colonCount);
}
// if the component is not a NamingContainer, then we need to
// get the component's naming container and set this as the 'from'.
if (!(from instanceof NamingContainer))
{
from = _getParentNamingContainer(from);
}
// pop out of the naming containers if there are multiple colons
// from will be null if there are no more naming containers
for (int j = 1; j < colonCount; j++)
{
from = _getParentNamingContainer(from);
}
// assumption is no one but the parent naming container modifies its
// client id
if (from == null)
return relativeId;
else
{
return (from.getClientId(context) +
NamingContainer.SEPARATOR_CHAR + relativeId);
}
}
// Given a component, get its naming container. If the component
// is a naming container, it will get its naming container.
// This is different than the one in ComponentUtils. This one
// returns null if there are no NamingContainers. The other one
// returns the ViewRoot.
private static UIComponent _getParentNamingContainer (
UIComponent from)
{
while (from != null && from.getParent() != null)
{
from = from.getParent();
if (from instanceof NamingContainer)
return from;
}
return null;
}
// Figure out how many colons
private static int _getColonCount(String relativeId)
{
int idLength = relativeId.length();
int colonCount = 0;
while (colonCount < idLength)
{
if (relativeId.charAt(colonCount) != NamingContainer.SEPARATOR_CHAR)
break;
colonCount++;
}
return colonCount;
}
static private final TrinidadLogger _LOG =
TrinidadLogger.createTrinidadLogger(RenderUtils.class);
}