PreviousExpressionResolver.java

/*
 * Copyright 2009-2014 PrimeTek.
 *
 * 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 org.primefaces.expression.impl;

import java.util.List;

import javax.faces.component.UIComponent;

import org.primefaces.expression.SearchExpressionResolver;

/**
 * {@link SearchExpressionResolver} for the "@previous" keyword.
 */
public class PreviousExpressionResolver implements SearchExpressionResolver {

	public UIComponent resolve(UIComponent source, UIComponent last, String expression) {
		UIComponent parent = last.getParent();

		if (parent.getChildCount() > 1) {
			List<UIComponent> children = parent.getChildren();
			int index = children.indexOf(last);

			if (index > 0)
			{
				return children.get(index - 1);
			}			
		}

		return null;
	}

}