1 /*
  2  * Copyright (c) 2019, 2026, 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 8326879
 27  * @summary Basic tests for serializing and deserializing record classes
 28  * @run junit RecordClassTest
 29  * @run testng/othervm --enable-preview RecordClassTest
 30  */
 31 
 32 import java.io.ByteArrayInputStream;
 33 import java.io.ByteArrayOutputStream;
 34 import java.io.Externalizable;
 35 import java.io.IOException;
 36 import java.io.ObjectInput;
 37 import java.io.ObjectInputStream;
 38 import java.io.ObjectOutput;
 39 import java.io.ObjectOutputStream;
 40 import java.io.ObjectStreamClass;
 41 import java.io.Serial;
 42 import java.io.Serializable;
 43 import static java.lang.System.out;
 44 
 45 import static org.junit.jupiter.api.Assertions.assertEquals;
 46 import static org.junit.jupiter.api.Assertions.fail;
 47 import org.junit.jupiter.api.TestInstance;
 48 import org.junit.jupiter.params.ParameterizedTest;
 49 import org.junit.jupiter.params.provider.MethodSource;
 50 
 51 /**
 52  * Serializes and deserializes record classes. Ensures that the SUID is 0.
 53  */
 54 public class RecordClassTest {
 55 
 56     record Foo () implements Serializable { }
 57 
 58     record Bar (int x) implements Serializable {
 59         @Serial
 60         private static final long serialVersionUID = 987654321L;
 61     }
 62 
 63     record Baz (Foo foo, Bar bar, int i) implements Serializable {  }
 64 
 65     interface ThrowingExternalizable extends Externalizable {
 66         default void writeExternal(ObjectOutput out) {
 67             fail("should not reach here");
 68         }
 69         default void readExternal(ObjectInput in) {
 70             fail("should not reach here");
 71         }
 72     }
 73 
 74     record Wibble () implements ThrowingExternalizable {
 75         @Serial
 76         private static final long serialVersionUID = 12345678L;
 77     }
 78 
 79     record Wobble (long l) implements ThrowingExternalizable { }
 80 
 81     record Wubble (Wobble wobble, Wibble wibble, String s) implements ThrowingExternalizable { }
 82 
 83     public static Object[][] recordClasses() {
 84         return new Object[][] {
 85             new Object[] { Foo.class    , 0L         },
 86             new Object[] { Bar.class    , 987654321L },
 87             new Object[] { Baz.class    , 0L         },
 88             new Object[] { Wibble.class , 12345678L  },
 89             new Object[] { Wobble.class , 0L         },
 90             new Object[] { Wubble.class , 0L         },
 91         };
 92     }
 93 
 94     /** Tests that the serialized and deserialized instances are equal. */
 95     @ParameterizedTest
 96     @MethodSource("recordClasses")
 97     public void testClassSerialization(Class<?> recordClass, long unused)
 98         throws Exception
 99     {
100         out.println("\n---");
101         out.println("serializing : " + recordClass);
102         var deserializedClass = serializeDeserialize(recordClass);
103         out.println("deserialized: " + deserializedClass);
104         assertEquals(deserializedClass, recordClass);
105         assertEquals(recordClass, deserializedClass);
106     }
107 
108     /** Tests that the SUID is always 0 unless explicitly declared. */
109     @ParameterizedTest
110     @MethodSource("recordClasses")
111     public void testSerialVersionUID(Class<?> recordClass, long expectedUID) {
112         out.println("\n---");
113         ObjectStreamClass osc = ObjectStreamClass.lookup(recordClass);
114         out.println("ObjectStreamClass::lookup  : " + osc);
115         assertEquals(expectedUID, osc.getSerialVersionUID());
116 
117         osc = ObjectStreamClass.lookupAny(recordClass);
118         out.println("ObjectStreamClass::lookupAny: " + osc);
119         assertEquals(expectedUID, osc.getSerialVersionUID());
120     }
121 
122     // --- not Serializable
123 
124     record NotSerializable1() { }
125 
126     record NotSerializable2(int x) { }
127 
128     record NotSerializable3<T>(T t) { }
129 
130     public static Object[][] notSerRecordClasses() {
131         return new Object[][] {
132             new Object[] { NotSerializable1.class },
133             new Object[] { NotSerializable2.class },
134             new Object[] { NotSerializable3.class },
135         };
136     }
137 
138     /** Tests that the generated SUID is always 0 for all non-Serializable record classes. */
139     @ParameterizedTest
140     @MethodSource("notSerRecordClasses")
141     public void testSerialVersionUIDNonSer(Class<?> recordClass) {
142         out.println("\n---");
143         ObjectStreamClass osc = ObjectStreamClass.lookup(recordClass);
144         out.println("ObjectStreamClass::lookup  : " + osc);
145         assertEquals(null, osc);
146 
147         osc = ObjectStreamClass.lookupAny(recordClass);
148         out.println("ObjectStreamClass::lookupAny: " + osc);
149         assertEquals(0L, osc.getSerialVersionUID());
150     }
151 
152     // --- infra
153 
154     static <T> byte[] serialize(T obj) throws IOException {
155         ByteArrayOutputStream baos = new ByteArrayOutputStream();
156         ObjectOutputStream oos = new ObjectOutputStream(baos);
157         oos.writeObject(obj);
158         oos.close();
159         return baos.toByteArray();
160     }
161 
162     @SuppressWarnings("unchecked")
163     static <T> T deserialize(byte[] streamBytes)
164         throws IOException, ClassNotFoundException
165     {
166         ByteArrayInputStream bais = new ByteArrayInputStream(streamBytes);
167         ObjectInputStream ois  = new ObjectInputStream(bais);
168         return (T) ois.readObject();
169     }
170 
171     static <T> T serializeDeserialize(T obj)
172         throws IOException, ClassNotFoundException
173     {
174         return deserialize(serialize(obj));
175     }
176 }