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/*
* Copyright (C) 2007 The Guava Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.common.testing;
import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import junit.framework.Assert;
import junit.framework.AssertionFailedError;
/**
* Tests serialization and deserialization of an object, optionally asserting that the resulting
* object is equal to the original.
*
* GWT warning: Under GWT, both methods simply returns their input, as proper GWT
* serialization tests require more setup. This no-op behavior allows test authors to intersperse
* {@code SerializableTester} calls with other, GWT-compatible tests.
*
* @author Mike Bostock
* @since 10.0
*/
@GwtCompatible // but no-op!
@ElementTypesAreNonnullByDefault
public final class SerializableTester {
private SerializableTester() {}
/**
* Serializes and deserializes the specified object.
*
*
GWT warning: Under GWT, this method simply returns its input, as proper GWT
* serialization tests require more setup. This no-op behavior allows test authors to intersperse
* {@code SerializableTester} calls with other, GWT-compatible tests.
*
*
Note that the specified object may not be known by the compiler to be a {@link
* java.io.Serializable} instance, and is thus declared an {@code Object}. For example, it might
* be declared as a {@code List}.
*
* @return the re-serialized object
* @throws RuntimeException if the specified object was not successfully serialized or
* deserialized
*/
@CanIgnoreReturnValue
public static T reserialize(T object) {
return Platform.reserialize(object);
}
/**
* Serializes and deserializes the specified object and verifies that the re-serialized object is
* equal to the provided object, that the hashcodes are identical, and that the class of the
* re-serialized object is identical to that of the original.
*
* GWT warning: Under GWT, this method simply returns its input, as proper GWT
* serialization tests require more setup. This no-op behavior allows test authors to intersperse
* {@code SerializableTester} calls with other, GWT-compatible tests.
*
*
Note that the specified object may not be known by the compiler to be a {@link
* java.io.Serializable} instance, and is thus declared an {@code Object}. For example, it might
* be declared as a {@code List}.
*
*
Note also that serialization is not in general required to return an object that is
* {@linkplain Object#equals equal} to the original, nor is it required to return even an object
* of the same class. For example, if sublists of {@code MyList} instances were serializable,
* those sublists might implement a private {@code MySubList} type but serialize as a plain {@code
* MyList} to save space. So long as {@code MyList} has all the public supertypes of {@code
* MySubList}, this is safe. For these cases, for which {@code reserializeAndAssert} is too
* strict, use {@link #reserialize}.
*
* @return the re-serialized object
* @throws RuntimeException if the specified object was not successfully serialized or
* deserialized
* @throws AssertionFailedError if the re-serialized object is not equal to the original object,
* or if the hashcodes are different.
*/
@CanIgnoreReturnValue
public static T reserializeAndAssert(T object) {
T copy = reserialize(object);
new EqualsTester().addEqualityGroup(object, copy).testEquals();
Assert.assertEquals(object.getClass(), copy.getClass());
return copy;
}
}