1/*
2 *  Licensed to the Apache Software Foundation (ASF) under one or more
3 *  contributor license agreements.  See the NOTICE file distributed with
4 *  this work for additional information regarding copyright ownership.
5 *  The ASF licenses this file to You under the Apache License, Version 2.0
6 *  (the "License"); you may not use this file except in compliance with
7 *  the License.  You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 *  Unless required by applicable law or agreed to in writing, software
12 *  distributed under the License is distributed on an "AS IS" BASIS,
13 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 *  See the License for the specific language governing permissions and
15 *  limitations under the License.
16 */
17
18package libcore.java.io;
19
20import java.io.ByteArrayOutputStream;
21import java.io.InputStream;
22import java.io.ObjectOutputStream;
23import java.util.Arrays;
24import junit.framework.TestCase;
25import tests.support.Support_GetPutFields;
26import tests.support.Support_GetPutFieldsDeprecated;
27
28/**
29 * Tests the methods of {@code ObjectOutputStream.PutField}. Three things make
30 * this class somewhat difficult to test:
31 * <ol>
32 * <li>It is a completely abstract class; none of the methods is implemented in
33 * {@code ObjectOutputStream.PutField}.</li>
34 * <li>There is no public class that implements
35 * {@code ObjectOutputStream.PutField}. The only way to get an implementation
36 * is by calling {@code ObjectOutputStream.putFields()}.</li>
37 * <li>Invoking the methods of {@code ObjectOutputStream.PutField} only works
38 * from within the private {@code writeObject(ObjectOutputStream)} method of a
39 * class that implements {@code Serializable}; an exception is thrown
40 * otherwise.</li>
41 * </ol>
42 * <p>
43 * Given these restrictions, an indirect approach is used to test
44 * {@code ObjectOutputStream.PutField}: The serializable helper class
45 * {@code tests.support.Support_GetPutFields} implements
46 * {@code writeObject(ObjectOutputStream)} and uses all {@code putX} methods in
47 * {@code PutField} to write data to the output stream. A second helper class,
48 * {@code tests.support.Support_GetPutFieldsDeprecated}, also uses the
49 * deprecated {@code ObjectOutputStream.PutField.write(ObjectOutput)}.
50 * {@code tests.util.FieldTestFileGenerator} can then be used on a reference
51 * platform to write these two classes to the file {@code testFields.ser} and
52 * {@code testFieldsDeprecated.ser} respectively.
53 * </p>
54 * <p>
55 * The test methods in this class expect to find {@code testFields.ser} and
56 * {@code testFieldsDeprecated.ser} as a resource stored at
57 * {@code tests/api/java/io}. The contents of these files is compared to what
58 * is written when {@code Support_GetPutFields.writeObject(ObjectOutputStream)}
59 * and {@code Support_GetPutFieldsDeprecated.writeObject(ObjectOutputStream)} is
60 * called by the test methods.
61 * </p>
62 */
63public class OldObjectOutputStreamPutFieldTest extends TestCase {
64
65    private final String FILENAME =
66        "/tests/api/java/io/testFields.ser";
67    private final String DEPRECATED_FILENAME =
68        "/tests/api/java/io/testFieldsDeprecated.ser";
69
70    public void test_put() throws Exception {
71        Support_GetPutFields toSerialize = new Support_GetPutFields();
72        byte[] content;
73        byte[] refContent;
74        ObjectOutputStream oos = null;
75        ByteArrayOutputStream baos;
76
77        toSerialize.initTestValues();
78
79        try {
80            refContent = getRefContent(FILENAME);
81
82            baos = new ByteArrayOutputStream(refContent.length);
83            oos = new ObjectOutputStream(baos);
84
85            oos.writeObject(toSerialize);
86            content = baos.toByteArray();
87            assertTrue("Serialization is not equal to reference platform.",
88                        Arrays.equals(content, refContent));
89        }
90        finally {
91            if (oos != null) oos.close();
92        }
93    }
94
95    public void test_writeLjava_io_ObjectOutputStream() throws Exception {
96        Support_GetPutFieldsDeprecated toSerialize = new Support_GetPutFieldsDeprecated();
97        byte[] content;
98        byte[] refContent;
99        ObjectOutputStream oos = null;
100        ByteArrayOutputStream baos;
101
102        toSerialize.initTestValues();
103
104        try {
105            refContent = getRefContent(DEPRECATED_FILENAME);
106
107            baos = new ByteArrayOutputStream(refContent.length);
108            oos = new ObjectOutputStream(baos);
109
110            oos.writeObject(toSerialize);
111            content = baos.toByteArray();
112            assertTrue("Serialization is not equal to reference platform.",
113                        Arrays.equals(content, refContent));
114        }
115        finally {
116            if (oos != null) oos.close();
117        }
118    }
119
120    private byte[] getRefContent(String path) throws Exception {
121        int bytesRead;
122        byte[] refContent;
123        byte[] streamContent = new byte[2000];
124        InputStream refStream = null;
125
126        try {
127            refStream = getClass().getResourceAsStream(path);
128            bytesRead = refStream.read(streamContent);
129            assertTrue("Test case implementation error: The byte array to " +
130                       "store the reference file is too small.",
131                       (refStream.read() == -1));
132            refContent = new byte[bytesRead];
133            System.arraycopy(streamContent, 0, refContent, 0, bytesRead);
134        }
135        finally {
136            if (refStream != null) refStream.close();
137        }
138        return refContent;
139    }
140}
141