Java tutorial
/* * * 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.qpid.server.configuration; import java.io.File; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; import org.apache.commons.configuration.CompositeConfiguration; import org.apache.commons.configuration.Configuration; import org.apache.commons.configuration.ConfigurationException; import org.apache.commons.configuration.ConfigurationFactory; import org.apache.commons.configuration.SystemConfiguration; import org.apache.commons.configuration.XMLConfiguration; public class XmlConfigurationUtilities { // Our configuration class needs to make the interpolate method // public so it can be called below from the config method. public static class MyConfiguration extends CompositeConfiguration { public String interpolate(String obj) { return super.interpolate(obj); } } public static Configuration parseConfig(File file) throws ConfigurationException { ConfigurationFactory factory = new ConfigurationFactory(); factory.setConfigurationFileName(file.getAbsolutePath()); Configuration conf = factory.getConfiguration(); Iterator<?> keys = conf.getKeys(); if (!keys.hasNext()) { keys = null; conf = flatConfig(file); } return conf; } public final static Configuration flatConfig(File file) throws ConfigurationException { // We have to override the interpolate methods so that // interpolation takes place across the entirety of the // composite configuration. Without doing this each // configuration object only interpolates variables defined // inside itself. final MyConfiguration conf = new MyConfiguration(); conf.addConfiguration(new SystemConfiguration() { protected String interpolate(String o) { return conf.interpolate(o); } }); conf.addConfiguration(new XMLConfiguration(file) { protected String interpolate(String o) { return conf.interpolate(o); } }); return conf; } public static String escapeTagName(String name) { return name.replaceAll("\\.", "\\.\\."); } }