1 /* 2 * Copyright (C) 2009 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 17 package com.google.common.collect; 18 19 import com.google.common.annotations.GwtCompatible; 20 import java.io.Serializable; 21 import java.util.Arrays; 22 import org.checkerframework.checker.nullness.qual.Nullable; 23 24 /** 25 * A class that implements {@code Comparable} without generics, such as those found in libraries 26 * that support Java 1.4 and before. Our library needs to do the bare minimum to accommodate such 27 * types, though their use may still require an explicit type parameter and/or warning suppression. 28 * 29 * @author Kevin Bourrillion 30 */ 31 @SuppressWarnings({"ComparableType", "rawtypes"}) // https://github.com/google/guava/issues/989 32 @GwtCompatible 33 @ElementTypesAreNonnullByDefault 34 class LegacyComparable implements Comparable, Serializable { 35 static final LegacyComparable X = new LegacyComparable("x"); 36 static final LegacyComparable Y = new LegacyComparable("y"); 37 static final LegacyComparable Z = new LegacyComparable("z"); 38 39 static final Iterable<LegacyComparable> VALUES_FORWARD = Arrays.asList(X, Y, Z); 40 static final Iterable<LegacyComparable> VALUES_BACKWARD = Arrays.asList(Z, Y, X); 41 42 private final String value; 43 LegacyComparable(String value)44 LegacyComparable(String value) { 45 this.value = value; 46 } 47 48 @Override compareTo(Object object)49 public int compareTo(Object object) { 50 // This method is spec'd to throw CCE if object is of the wrong type 51 LegacyComparable that = (LegacyComparable) object; 52 return this.value.compareTo(that.value); 53 } 54 55 @Override equals(@ullable Object object)56 public boolean equals(@Nullable Object object) { 57 if (object instanceof LegacyComparable) { 58 LegacyComparable that = (LegacyComparable) object; 59 return this.value.equals(that.value); 60 } 61 return false; 62 } 63 64 @Override hashCode()65 public int hashCode() { 66 return value.hashCode(); 67 } 68 69 private static final long serialVersionUID = 0; 70 } 71