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