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 * 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.
 *
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// key: compiler.warn.ineffectual.serial.method.externalizable
// key: compiler.warn.ineffectual.serial.field.externalizable
// key: compiler.warn.externalizable.missing.public.no.arg.ctor

// options: -Xlint:serial

import java.io.*;

class IneffectualSerialExtern implements Externalizable {
    private static final long serialVersionUID = 42;

    // Must have a public no-arg constructor
    public IneffectualSerialExtern(int foo) {}

    public void writeExternal(ObjectOutput out) throws IOException {
        return;
    }

    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
        return;
    }

    // ineffectual
    private static final ObjectStreamField[] serialPersistentFields = {};

    // The readObject method is ineffectual for Externalizable classes.
    private void readObject(ObjectInputStream stream)
        throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        return;
    }
}