org.primefaces.expression.impl.ChildExpressionResolver Maven / Gradle / Ivy
/*
* 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.regex.Matcher;
import java.util.regex.Pattern;
import javax.faces.FacesException;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import org.primefaces.expression.SearchExpressionResolver;
/**
* {@link SearchExpressionResolver} for the "@child" keyword.
*/
public class ChildExpressionResolver implements SearchExpressionResolver {
private static final Pattern PATTERN = Pattern.compile("@child\\((\\d+)\\)");
public UIComponent resolveComponent(FacesContext context, UIComponent source, UIComponent last, String expression) {
try {
Matcher matcher = PATTERN.matcher(expression);
if (matcher.matches()) {
int childNumber = Integer.parseInt(matcher.group(1));
if (childNumber + 1 > last.getChildCount()) {
throw new FacesException("Component with clientId \"" +
last.getClientId(context) + "\" has fewer children as \"" + childNumber + "\". Expression: \"" + expression + "\"");
}
return last.getChildren().get(childNumber);
} else {
throw new FacesException("Expression does not match following pattern @child(n). Expression: \"" + expression + "\"");
}
} catch (Exception e) {
throw new FacesException("Expression does not match following pattern @child(n). Expression: \"" + expression + "\"", e);
}
}
}