/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/* @test

 * @bug 4227189

 * @summary Ensure that class descriptor read, write hooks exist, are backwards

 *          compatible, and work as advertised.

 */

import java.io.*;

import java.util.*;

class Foo implements Serializable {

    private static final long serialVersionUID = 1L;

    public boolean equals(Object obj) {

        if (obj instanceof Foo) {

            Foo ofoo = (Foo) obj;

            return s.equals(ofoo.s) && i.equals(ofoo.i) && l.equals(ofoo.l);

        }

        return false;

    }

}

class CustomOutputStream extends ObjectOutputStream {

    boolean hookCalled = false;

    CustomOutputStream(OutputStream out) throws IOException {

        super(out);

        useProtocolVersion(PROTOCOL_VERSION_2);

    }

    protected void writeClassDescriptor(ObjectStreamClass desc)

        throws IOException

    {

        writeUTF(desc.getName());

        hookCalled = true;

    }

}

class CustomInputStream extends ObjectInputStream {

    boolean hookCalled = false;

    CustomInputStream(InputStream in) throws IOException {

        super(in);

    }

    protected ObjectStreamClass readClassDescriptor()

        throws IOException, ClassNotFoundException

    {

        hookCalled = true;

        return ObjectStreamClass.lookup(Class.forName(readUTF()));

    }

}

public class ClassDescHooks implements ObjectStreamConstants {

    public static void main(String[] args) throws Exception {

        ByteArrayOutputStream bout;

        ByteArrayInputStream bin;

        ObjectOutputStream oout;

        ObjectInputStream oin;

        FileInputStream fin;

        File foof;

        CustomOutputStream cout;

        CustomInputStream cin;

        // test for backwards compatibility

        bout = new ByteArrayOutputStream();

        foof = new File(System.getProperty("test.src", "."), "Foo.ser");

        fin = new FileInputStream(foof);

        try {

            while (fin.available() > 0)

                bout.write(fin.read());

        } finally {

            fin.close();

        }

        byte[] buf1 = bout.toByteArray();

        bout = new ByteArrayOutputStream();

        oout = new ObjectOutputStream(bout);

        Foo foo = new Foo();

        oout.writeObject(foo);

        oout.flush();

        byte[] buf2 = bout.toByteArray();

        if (! Arrays.equals(buf1, buf2))

            throw new Error("Incompatible stream format (write)");

        Foo foocopy;

        fin = new FileInputStream(foof);

        try {

            oin = new ObjectInputStream(fin);

            foocopy = (Foo) oin.readObject();

            if (! foo.equals(foocopy))

                throw new Error("Incompatible stream format (read)");

        } finally {

            fin.close();

        }

        // make sure write hook not called when old protocol in use

        bout = new ByteArrayOutputStream();

        cout = new CustomOutputStream(bout);

        cout.useProtocolVersion(PROTOCOL_VERSION_1);

        cout.writeObject(foo);

        if (cout.hookCalled)

            throw new Error("write descriptor hook should not be called");

        // write custom class descriptor representations

        bout = new ByteArrayOutputStream();

        cout = new CustomOutputStream(bout);

        cout.writeObject(foo);

        cout.flush();

        bin = new ByteArrayInputStream(bout.toByteArray());

        cin = new CustomInputStream(bin);

        foocopy = (Foo) cin.readObject();

        if (! cout.hookCalled)

            throw new Error("write descriptor hook never called");

        if (! cin.hookCalled)

            throw new Error("read descriptor hook never called");

        if (! foo.equals(foocopy))

            throw new Error("serialization failed when hooks active");

    }

}