/*
* Copyright 2009 Sven Meier
*
* 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.
*/
package wicketdnd.util;
import org.apache.wicket.Component;
import org.apache.wicket.MarkupContainer;
import org.apache.wicket.protocol.http.PageExpiredException;
import org.apache.wicket.util.visit.IVisit;
import org.apache.wicket.util.visit.IVisitor;
/**
* Find a child component by it's markup id.
*
* @author Sven Meier
*/
public class MarkupIdVisitor implements IVisitor<Component,Component> {
private final String id;
public MarkupIdVisitor(String id) {
if (id == null) {
throw new IllegalArgumentException("id must not be null");
}
this.id = id;
}
public void component(Component component, final IVisit<Component> visit) {
if (id.equals(component.getMarkupId(false))) {
visit.stop(component);
}
}
/**
* Get the given container's descendent by markup id.
*
* @param container
* container to find descendent of
* @param id
* markup id
* @return component
* @throws PageExpiredException
* if no descendent has the given markup id
*/
public static Component getComponent(MarkupContainer container, String id) {
if (id.equals(container.getMarkupId(false))) {
return container;
}
Component component = container
.visitChildren(new MarkupIdVisitor(id));
if (component == null) {
throw new PageExpiredException("No component with markup id " + id);
}
return component;
}
}