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 17 package com.google.common.testing; 18 19 import com.google.common.annotations.Beta; 20 import com.google.common.annotations.GwtCompatible; 21 22 import junit.framework.Assert; 23 import junit.framework.AssertionFailedError; 24 25 /** 26 * Tests serialization and deserialization of an object, optionally asserting 27 * that the resulting object is equal to the original. 28 * 29 * <p><b>GWT warning:</b> Under GWT, both methods simply returns their input, 30 * as proper GWT serialization tests require more setup. This no-op behavior 31 * allows test authors to intersperse {@code SerializableTester} calls with 32 * other, GWT-compatible tests. 33 * 34 * 35 * @author Mike Bostock 36 * @since 10.0 37 */ 38 @Beta 39 @GwtCompatible // but no-op! 40 public final class SerializableTester { 41 private SerializableTester() {} 42 43 /** 44 * Serializes and deserializes the specified object. 45 * 46 * <p><b>GWT warning:</b> Under GWT, this method simply returns its input, as 47 * proper GWT serialization tests require more setup. This no-op behavior 48 * allows test authors to intersperse {@code SerializableTester} calls with 49 * other, GWT-compatible tests. 50 * 51 * <p>Note that the specified object may not be known by the compiler to be a 52 * {@link java.io.Serializable} instance, and is thus declared an 53 * {@code Object}. For example, it might be declared as a {@code List}. 54 * 55 * @return the re-serialized object 56 * @throws RuntimeException if the specified object was not successfully 57 * serialized or deserialized 58 */ 59 @SuppressWarnings("unchecked") 60 public static <T> T reserialize(T object) { 61 return Platform.reserialize(object); 62 } 63 64 /** 65 * Serializes and deserializes the specified object and verifies that the 66 * re-serialized object is equal to the provided object, that the hashcodes 67 * are identical, and that the class of the re-serialized object is identical 68 * to that of the original. 69 * 70 * <p><b>GWT warning:</b> Under GWT, this method simply returns its input, as 71 * proper GWT serialization tests require more setup. This no-op behavior 72 * allows test authors to intersperse {@code SerializableTester} calls with 73 * other, GWT-compatible tests. 74 * 75 * <p>Note that the specified object may not be known by the compiler to be a 76 * {@link java.io.Serializable} instance, and is thus declared an 77 * {@code Object}. For example, it might be declared as a {@code List}. 78 * 79 * <p>Note also that serialization is not in general required to return an 80 * object that is {@linkplain Object#equals equal} to the original, nor is it 81 * required to return even an object of the same class. For example, if 82 * sublists of {@code MyList} instances were serializable, those sublists 83 * might implement a private {@code MySubList} type but serialize as a plain 84 * {@code MyList} to save space. So long as {@code MyList} has all the public 85 * supertypes of {@code MySubList}, this is safe. For these cases, for which 86 * {@code reserializeAndAssert} is too strict, use {@link #reserialize}. 87 * 88 * @return the re-serialized object 89 * @throws RuntimeException if the specified object was not successfully 90 * serialized or deserialized 91 * @throws AssertionFailedError if the re-serialized object is not equal to 92 * the original object, or if the hashcodes are different. 93 */ 94 public static <T> T reserializeAndAssert(T object) { 95 T copy = reserialize(object); 96 new EqualsTester() 97 .addEqualityGroup(object, copy) 98 .testEquals(); 99 Assert.assertEquals(object.getClass(), copy.getClass()); 100 return copy; 101 } 102 } 103
