LangAttributePointer.java

/*
 * 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.
 */
/*******************************************************************************
 * Copyright (c) 2010 BestSolution.at and others. All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License v1.0 which accompanies this distribution, and is
 * available at http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors: Tom Schindl <tom.schindl@bestsolution.at> - adjustment to EObject
 ******************************************************************************/
package org.eclipse.e4.emf.internal.xpath;

import org.apache.commons.jxpath.ri.QName;
import org.apache.commons.jxpath.ri.compiler.NodeTest;
import org.apache.commons.jxpath.ri.model.NodePointer;

/**
 * A Pointer that points to the "lang" attribute of a JavaBean. The value of the attribute is based on the locale
 * supplied to it in the constructor.
 * 
 * 
 */
public class LangAttributePointer extends NodePointer {

	private static final long serialVersionUID = -8665319197100034134L;

	/**
	 * Create a new LangAttributePointer.
	 * 
	 * @param parent
	 *            parent pointer.
	 */
	public LangAttributePointer(NodePointer parent) {
		super(parent);
	}

	@Override
	public QName getName() {
		return new QName("xml", "lang");
	}

	@Override
	public String getNamespaceURI() {
		return null;
	}

	@Override
	public boolean isCollection() {
		return false;
	}

	@Override
	public int getLength() {
		return 1;
	}

	@Override
	public Object getBaseValue() {
		return parent.getLocale().toString().replace('_', '-');
	}

	@Override
	public Object getImmediateNode() {
		return getBaseValue();
	}

	@Override
	public boolean isLeaf() {
		return true;
	}

	/**
	 * {@inheritDoc}
	 * 
	 * Throws UnsupportedOperationException.
	 * 
	 * @param value
	 *            Object
	 */
	@Override
	public void setValue(Object value) {
		throw new UnsupportedOperationException("Cannot change locale using the 'lang' attribute");
	}

	@Override
	public String asPath() {
		StringBuffer buffer = new StringBuffer();
		if (parent != null) {
			buffer.append(parent.asPath());
			if (buffer.length() == 0 || buffer.charAt(buffer.length() - 1) != '/') {
				buffer.append('/');
			}
		}
		buffer.append("@xml:lang");
		return buffer.toString();
	}

	@Override
	public int hashCode() {
		return 0;
	}

	@Override
	public boolean equals(Object object) {
		return object instanceof LangAttributePointer;
	}

	@Override
	public boolean testNode(NodeTest test) {
		return false;
	}

	@Override
	public int compareChildNodePointers(NodePointer pointer1, NodePointer pointer2) {
		// Won't happen - lang attributes don't have children
		return 0;
	}
}