1 /*
  2  * Copyright (c) 2019, 2025, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  */
 23 
 24 /*
 25  * @test
 26  * @bug 8246774
 27  * @summary Basic tests for serializing and deserializing record classes
 28  * @run junit RecordClassTest
 29  */
 30 
 31 import java.io.ByteArrayInputStream;
 32 import java.io.ByteArrayOutputStream;
 33 import java.io.Externalizable;
 34 import java.io.IOException;
 35 import java.io.ObjectInput;
 36 import java.io.ObjectInputStream;
 37 import java.io.ObjectOutput;
 38 import java.io.ObjectOutputStream;
 39 import java.io.ObjectStreamClass;
 40 import java.io.Serializable;
 41 import static java.lang.System.out;
 42 
 43 import static org.junit.jupiter.api.Assertions.assertEquals;
 44 import static org.junit.jupiter.api.Assertions.fail;
 45 import org.junit.jupiter.api.TestInstance;
 46 import org.junit.jupiter.params.ParameterizedTest;
 47 import org.junit.jupiter.params.provider.MethodSource;
 48 
 49 /**
 50  * Serializes and deserializes record classes. Ensures that the SUID is 0.
 51  */
 52 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 53 public class RecordClassTest {
 54 
 55     record Foo () implements Serializable { }
 56 
 57     record Bar (int x) implements Serializable {
 58         private static final long serialVersionUID = 987654321L;
 59     }
 60 
 61     record Baz (Foo foo, Bar bar, int i) implements Serializable {  }
 62 
 63     interface ThrowingExternalizable extends Externalizable {
 64         default void writeExternal(ObjectOutput out) {
 65             fail("should not reach here");
 66         }
 67         default void readExternal(ObjectInput in) {
 68             fail("should not reach here");
 69         }
 70     }
 71 
 72     record Wibble () implements ThrowingExternalizable {
 73         private static final long serialVersionUID = 12345678L;
 74     }
 75 
 76     record Wobble (long l) implements ThrowingExternalizable { }
 77 
 78     record Wubble (Wobble wobble, Wibble wibble, String s) implements ThrowingExternalizable { }
 79 
 80     public Object[][] recordClasses() {
 81         return new Object[][] {
 82             new Object[] { Foo.class    , 0L         },
 83             new Object[] { Bar.class    , 987654321L },
 84             new Object[] { Baz.class    , 0L         },
 85             new Object[] { Wibble.class , 12345678L  },
 86             new Object[] { Wobble.class , 0L         },
 87             new Object[] { Wubble.class , 0L         },
 88         };
 89     }
 90 
 91     /** Tests that the serialized and deserialized instances are equal. */
 92     @ParameterizedTest
 93     @MethodSource("recordClasses")
 94     public void testClassSerialization(Class<?> recordClass, long unused)
 95         throws Exception
 96     {
 97         out.println("\n---");
 98         out.println("serializing : " + recordClass);
 99         var deserializedClass = serializeDeserialize(recordClass);
100         out.println("deserialized: " + deserializedClass);
101         assertEquals(deserializedClass, recordClass);
102         assertEquals(recordClass, deserializedClass);
103     }
104 
105     /** Tests that the SUID is always 0 unless explicitly declared. */
106     @ParameterizedTest
107     @MethodSource("recordClasses")
108     public void testSerialVersionUID(Class<?> recordClass, long expectedUID) {
109         out.println("\n---");
110         ObjectStreamClass osc = ObjectStreamClass.lookup(recordClass);
111         out.println("ObjectStreamClass::lookup  : " + osc);
112         assertEquals(expectedUID, osc.getSerialVersionUID());
113 
114         osc = ObjectStreamClass.lookupAny(recordClass);
115         out.println("ObjectStreamClass::lookupAny: " + osc);
116         assertEquals(expectedUID, osc.getSerialVersionUID());
117     }
118 
119     // --- not Serializable
120 
121     record NotSerializable1() { }
122 
123     record NotSerializable2(int x) { }
124 
125     record NotSerializable3<T>(T t) { }
126 
127     public Object[][] notSerRecordClasses() {
128         return new Object[][] {
129             new Object[] { NotSerializable1.class },
130             new Object[] { NotSerializable2.class },
131             new Object[] { NotSerializable3.class },
132         };
133     }
134 
135     /** Tests that the generated SUID is always 0 for all non-Serializable record classes. */
136     @ParameterizedTest
137     @MethodSource("notSerRecordClasses")
138     public void testSerialVersionUIDNonSer(Class<?> recordClass) {
139         out.println("\n---");
140         ObjectStreamClass osc = ObjectStreamClass.lookup(recordClass);
141         out.println("ObjectStreamClass::lookup  : " + osc);
142         assertEquals(null, osc);
143 
144         osc = ObjectStreamClass.lookupAny(recordClass);
145         out.println("ObjectStreamClass::lookupAny: " + osc);
146         assertEquals(0L, osc.getSerialVersionUID());
147     }
148 
149     // --- infra
150 
151     static <T> byte[] serialize(T obj) throws IOException {
152         ByteArrayOutputStream baos = new ByteArrayOutputStream();
153         ObjectOutputStream oos = new ObjectOutputStream(baos);
154         oos.writeObject(obj);
155         oos.close();
156         return baos.toByteArray();
157     }
158 
159     @SuppressWarnings("unchecked")
160     static <T> T deserialize(byte[] streamBytes)
161         throws IOException, ClassNotFoundException
162     {
163         ByteArrayInputStream bais = new ByteArrayInputStream(streamBytes);
164         ObjectInputStream ois  = new ObjectInputStream(bais);
165         return (T) ois.readObject();
166     }
167 
168     static <T> T serializeDeserialize(T obj)
169         throws IOException, ClassNotFoundException
170     {
171         return deserialize(serialize(obj));
172     }
173 }