/*
* (C) Copyright 2010 Nuxeo SA (http://nuxeo.com/) and others.
*
* Licensed 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.
*
* Contributors:
* Anahide Tchertchian
*/
package org.nuxeo.ecm.platform.ui.web.binding.alias;
import java.io.IOException;
import java.util.List;
import javax.faces.FacesException;
import javax.faces.component.ContextCallback;
import javax.faces.component.UIComponent;
import javax.faces.component.UIOutput;
import javax.faces.component.visit.VisitCallback;
import javax.faces.component.visit.VisitContext;
import javax.faces.context.FacesContext;
import javax.faces.event.FacesEvent;
import javax.faces.event.PhaseId;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.nuxeo.ecm.platform.ui.web.tag.handler.SetTagHandler;
import com.sun.faces.facelets.tag.jsf.ComponentSupport;
/**
* Holder component for value expressions.
* <p>
* Since 6.0 and JSF2 migration, exposed values are now stored in a view-scoped managed bean and do not need to be
* exposed again at render time.
* <p>
* This component is still interesting to anchor the component in the tree, and make sure its children are reset on ajax
* requests, when the value it holds can have an impact on the underlying components. In this case, it is instantiated
* by the {@link AliasTagHandler} or {@link SetTagHandler} facelet handlers, depending on their instantiation criteria.
*
* @author Anahide Tchertchian
* @since 5.4
* @see AliasTagHandler
* @see SetTagHandler
*/
public class UIAliasHolder extends UIOutput {
private static final Log log = LogFactory.getLog(UIAliasHolder.class);
public static final String COMPONENT_TYPE = UIAliasHolder.class.getName();
public static final String COMPONENT_FAMILY = UIAliasHolder.class.getName();
/**
* Keep the alias transient: it's supposed to be set at build time by facelet handlers and does not need to be
* restored/saved.
*
* @since 6.0
*/
protected transient AliasVariableMapper alias;
public UIAliasHolder() {
super();
}
@Override
public String getFamily() {
return COMPONENT_FAMILY;
}
@Override
public String getRendererType() {
return null;
}
@Override
public void setRendererType(String rendererType) {
// do nothing
}
@Override
public boolean isRendered() {
return true;
}
@Override
public void setRendered(boolean rendered) {
// do nothing
}
@Override
public boolean getRendersChildren() {
return true;
}
@Override
public void broadcast(FacesEvent event) {
if (event instanceof AliasEvent) {
FacesContext context = getFacesContext();
AliasVariableMapper alias = getAliasVariableMapper();
try {
AliasVariableMapper.exposeAliasesToRequest(context, alias);
FacesEvent origEvent = ((AliasEvent) event).getOriginalEvent();
origEvent.getComponent().broadcast(origEvent);
} finally {
if (alias != null) {
AliasVariableMapper.removeAliasesExposedToRequest(context, alias.getId());
}
}
} else {
super.broadcast(event);
}
}
@Override
public void queueEvent(FacesEvent event) {
event = new AliasEvent(this, event);
super.queueEvent(event);
}
@Override
public boolean invokeOnComponent(FacesContext context, String clientId, ContextCallback callback)
throws FacesException {
AliasVariableMapper alias = getAliasVariableMapper();
try {
AliasVariableMapper.exposeAliasesToRequest(context, alias);
return super.invokeOnComponent(context, clientId, callback);
} finally {
if (alias != null) {
AliasVariableMapper.removeAliasesExposedToRequest(context, alias.getId());
}
}
}
@Override
public void encodeBegin(FacesContext context) throws IOException {
AliasVariableMapper alias = getAliasVariableMapper();
AliasVariableMapper.exposeAliasesToRequest(context, alias);
super.encodeBegin(context);
}
@Override
public void encodeChildren(final FacesContext context) throws IOException {
// no need to expose variables: already done in #encodeBegin
processFacetsAndChildren(context, PhaseId.RENDER_RESPONSE);
}
@Override
public void encodeEnd(FacesContext context) throws IOException {
AliasVariableMapper alias = getAliasVariableMapper();
if (alias != null) {
AliasVariableMapper.removeAliasesExposedToRequest(context, alias.getId());
}
}
@Override
public void processDecodes(FacesContext context) {
processFacetsAndChildrenWithVariables(context, PhaseId.APPLY_REQUEST_VALUES);
}
@Override
public void processValidators(FacesContext context) {
processFacetsAndChildrenWithVariables(context, PhaseId.PROCESS_VALIDATIONS);
}
@Override
public void processUpdates(FacesContext context) {
processFacetsAndChildrenWithVariables(context, PhaseId.UPDATE_MODEL_VALUES);
}
protected final void processFacetsAndChildren(final FacesContext context, final PhaseId phaseId) {
List<UIComponent> stamps = getChildren();
for (UIComponent stamp : stamps) {
processComponent(context, stamp, phaseId);
}
}
protected final void processFacetsAndChildrenWithVariables(final FacesContext context, final PhaseId phaseId) {
AliasVariableMapper alias = getAliasVariableMapper();
try {
AliasVariableMapper.exposeAliasesToRequest(context, alias);
processFacetsAndChildren(context, phaseId);
} finally {
if (alias != null) {
AliasVariableMapper.removeAliasesExposedToRequest(context, alias.getId());
}
}
}
protected final void processComponent(FacesContext context, UIComponent component, PhaseId phaseId) {
if (component != null) {
if (phaseId == PhaseId.APPLY_REQUEST_VALUES) {
component.processDecodes(context);
} else if (phaseId == PhaseId.PROCESS_VALIDATIONS) {
component.processValidators(context);
} else if (phaseId == PhaseId.UPDATE_MODEL_VALUES) {
component.processUpdates(context);
} else if (phaseId == PhaseId.RENDER_RESPONSE) {
try {
ComponentSupport.encodeRecursive(context, component);
} catch (IOException err) {
log.error("Error while rendering component " + component);
}
} else {
throw new IllegalArgumentException("Bad PhaseId:" + phaseId);
}
}
}
/**
* @since 6.0
*/
public AliasVariableMapper getAlias() {
return alias;
}
/**
* @since 6.0
*/
public void setAlias(AliasVariableMapper alias) {
this.alias = alias;
}
protected AliasVariableMapper getAliasVariableMapper() {
return getAlias();
}
@Override
public boolean visitTree(VisitContext visitContext, VisitCallback callback) {
if (!isVisitable(visitContext)) {
return false;
}
FacesContext facesContext = visitContext.getFacesContext();
AliasVariableMapper alias = getAliasVariableMapper();
try {
AliasVariableMapper.exposeAliasesToRequest(facesContext, alias);
return super.visitTree(visitContext, callback);
} finally {
if (alias != null) {
AliasVariableMapper.removeAliasesExposedToRequest(facesContext, alias.getId());
}
}
}
}