Serializable/writeReplace/WriteReplace.java

	WriteReplace.java revision 0
0N/A/*
553N/A * Copyright 2000 Sun Microsystems, Inc.  All Rights Reserved.
0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
0N/A *
0N/A * This code is free software; you can redistribute it and/or modify it
0N/A * under the terms of the GNU General Public License version 2 only, as
0N/A * published by the Free Software Foundation.
0N/A *
0N/A * This code is distributed in the hope that it will be useful, but WITHOUT
0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
0N/A * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
0N/A * version 2 for more details (a copy is included in the LICENSE file that
0N/A * accompanied this code).
0N/A *
0N/A * You should have received a copy of the GNU General Public License version
0N/A * 2 along with this work; if not, write to the Free Software Foundation,
0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
0N/A *
553N/A * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
553N/A * CA 95054 USA or visit www.sun.com if you need additional information or
553N/A * have any questions.
0N/A */
0N/A
0N/A/* @test
0N/A * @summary Test proper functioning of class-defined writeReplace methods.
0N/A */
0N/A
0N/Aimport java.io.*;
0N/A
0N/Apublic class WriteReplace {
0N/A
0N/A    static class ReplaceMe implements Serializable {
0N/A        private Object obj;
0N/A        private boolean writeReplaceCalled = false;
0N/A
        public ReplaceMe(Object obj) {
            this.obj = obj;
        }

        private Object writeReplace() throws ObjectStreamException {
            if (writeReplaceCalled) {
                throw new Error("multiple calls to writeReplace");
            }
            writeReplaceCalled = true;
            return obj;
        }
    }

    public static void main(String[] args) throws Exception {
        final int nobjs = 10;
        final int nrounds = 10;

        Object common = "foo";
        ReplaceMe[] objs = new ReplaceMe[nobjs];
        for (int i = 0; i < nobjs; i++) {
            objs[i] = new ReplaceMe(common);
        }

        ByteArrayOutputStream bout = new ByteArrayOutputStream();
        ObjectOutputStream oout = new ObjectOutputStream(bout);
        for (int i = 0; i < nrounds; i++) {
            for (int j = 0; j < nobjs; j++) {
                oout.writeObject(objs[j]);
            }
        }

        oout.flush();
        ByteArrayInputStream bin =
            new ByteArrayInputStream(bout.toByteArray());
        ObjectInputStream oin = new ObjectInputStream(bin);
        common = null;

        for (int i = 0; i < nrounds; i++) {
            for (int j = 0; j < nobjs; j++) {
                if (common == null) {
                    common = oin.readObject();
                } else {
                    if (oin.readObject() != common) {
                        throw new Error("incorrect replacement object");
                    }
                }
            }
        }
    }
}