001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.configuration2;
019
020import java.util.Iterator;
021
022/**
023 * Strict comparator for configurations.
024 *
025 * @since 1.0
026 */
027public class StrictConfigurationComparator implements ConfigurationComparator {
028    /**
029     * Create a new strict comparator.
030     */
031    public StrictConfigurationComparator() {
032    }
033
034    /**
035     * Compare two configuration objects.
036     *
037     * @param a the first configuration
038     * @param b the second configuration
039     * @return true if keys from a are found in b and keys from b are found in a and for each key in a, the corresponding
040     *         value is the sale in for the same key in b
041     */
042    @Override
043    public boolean compare(final Configuration a, final Configuration b) {
044        if (a == null && b == null) {
045            return true;
046        }
047        if (a == null || b == null) {
048            return false;
049        }
050
051        for (final Iterator<String> keys = a.getKeys(); keys.hasNext();) {
052            final String key = keys.next();
053            final Object value = a.getProperty(key);
054            if (!value.equals(b.getProperty(key))) {
055                return false;
056            }
057        }
058
059        for (final Iterator<String> keys = b.getKeys(); keys.hasNext();) {
060            final String key = keys.next();
061            final Object value = b.getProperty(key);
062            if (!value.equals(a.getProperty(key))) {
063                return false;
064            }
065        }
066
067        return true;
068    }
069}