src/main/java/org/apache/vysper/xml/sax/impl/StackNamespaceResolver2.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.
 *
 */

package org.apache.vysper.xml.sax.impl;

import java.util.Map;
import java.util.Stack;
import java.util.Map.Entry;

import org.apache.vysper.xml.fragment.NamespaceResolver;
import org.apache.vysper.xml.fragment.Namespaces;


/**
 * Naive implementation, will be replaced in later stages of this change
 */
public class StackNamespaceResolver2 {
	
	private Stack<Map<String, String>> elements = new Stack<Map<String, String>>();
	
	public StackNamespaceResolver2() {
	}

	public void push(Map<String, String> elmXmlns) {
		elements.push(elmXmlns);
	}

	public void pop() {
		elements.pop();
	}
	
	public String resolveUri(String prefix) {
		// check for the reserved xml namespace
		if(prefix.equals("xml")) {
			return Namespaces.XML;
		} else {
			// walk over the stack backwards
			for(int i = elements.size() - 1; i>=0; i--) {
				Map<String, String> ns = elements.get(i);
				if(ns.containsKey(prefix)) {
					return ns.get(prefix);
				}
			}
		}
		
		
		// could not resolve URI
		return null;
	}
	
	public String resolvePrefix(String uri) {
		if(uri.equals(Namespaces.XML)) {
			return "xml";
		} else {
			// walk over the stack backwards
			for(int i = elements.size() - 1; i>=0; i--) {
				Map<String, String> ns = elements.get(i);
				for(Entry<String, String> entry : ns.entrySet()) {
					if(entry.getValue().equals(uri)) {
						return entry.getKey();
					}
				}
			}
		}

		return null;
	}
}