1/* 2 * Copyright (C) 2007 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package com.google.common.collect; 18 19import com.google.common.annotations.GwtCompatible; 20 21import java.io.Serializable; 22 23/** 24 * An ordering that uses the natural order of the string representation of the 25 * values. 26 */ 27@GwtCompatible(serializable = true) 28final class UsingToStringOrdering 29 extends Ordering<Object> implements Serializable { 30 static final UsingToStringOrdering INSTANCE = new UsingToStringOrdering(); 31 32 @Override public int compare(Object left, Object right) { 33 return left.toString().compareTo(right.toString()); 34 } 35 36 // preserve singleton-ness, so equals() and hashCode() work correctly 37 private Object readResolve() { 38 return INSTANCE; 39 } 40 41 @Override public String toString() { 42 return "Ordering.usingToString()"; 43 } 44 45 private UsingToStringOrdering() {} 46 47 private static final long serialVersionUID = 0; 48} 49