1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package org.apache.commons.collections4.junit; 19 20 import java.io.Serializable; 21 import java.util.Comparator; 22 23 public final class ObjectToStringComparator implements Comparator<Object>, Serializable { 24 25 /** 26 * Singleton instance. 27 */ 28 public static final ObjectToStringComparator INSTANCE = new ObjectToStringComparator(); 29 30 private static final long serialVersionUID = 1L; 31 32 @Override 33 public int compare(final Object o1, final Object o2) { 34 if (o1 == null && o2 == null) { 35 return 0; 36 } 37 if (o1 == null) { 38 return 1; 39 } 40 if (o2 == null) { 41 return -1; 42 } 43 return o1.toString().compareTo(o2.toString()); 44 } 45 } 46