/*
 * Copyright 1999-2008 Sun Microsystems, Inc.  All Rights Reserved.
 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

/*
 *
 */

package bench.serial;

import bench.Benchmark;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectInputStream;
import java.io.ObjectOutput;
import java.io.ObjectOutputStream;

/**
 * Benchmark for testing speed of writes and reads of a tree of Externalizable
 * objects.
 */
public class ExternObjTrees implements Benchmark {

    static class Node implements Externalizable {
        boolean z;
        byte b;
        char c;
        short s;
        int i;
        float f;
        long j;
        double d;
        String str = "bodega";
        Object parent, left, right;

        Node(Object parent, int depth) {
            this.parent = parent;
            if (depth > 0) {
                left = new Node(this, depth - 1);
                right = new Node(this, depth - 1);
            }
        }

        public Node() {
        }

        public void writeExternal(ObjectOutput out) throws IOException {
            out.writeBoolean(z);
            out.writeByte(b);
            out.writeChar(c);
            out.writeShort(s);
            out.writeInt(i);
            out.writeFloat(f);
            out.writeLong(j);
            out.writeDouble(d);
            out.writeObject(str);
            out.writeObject(parent);
            out.writeObject(left);
            out.writeObject(right);
        }

        public void readExternal(ObjectInput in)
            throws IOException, ClassNotFoundException
        {
            z = in.readBoolean();
            b = in.readByte();
            c = in.readChar();
            s = in.readShort();
            i = in.readInt();
            f = in.readFloat();
            j = in.readLong();
            d = in.readDouble();
            str = (String) in.readObject();
            parent = in.readObject();
            left = in.readObject();
            right = in.readObject();
        }
    }

    /**
     * Write and read a tree of externalizable objects from a stream.  The
     * benchmark is run in batches: each "batch" consists of a fixed number of
     * read/write cycles, and the stream is flushed (and underlying stream
     * buffer cleared) in between each batch.
     * Arguments: <tree depth> <# batches> <# cycles per batch>
     */
    public long run(String[] args) throws Exception {
        int depth = Integer.parseInt(args[0]);
        int nbatches = Integer.parseInt(args[1]);
        int ncycles = Integer.parseInt(args[2]);
        Node[] trees = genTrees(depth, ncycles);
        StreamBuffer sbuf = new StreamBuffer();
        ObjectOutputStream oout =
            new ObjectOutputStream(sbuf.getOutputStream());
        ObjectInputStream oin =
            new ObjectInputStream(sbuf.getInputStream());

        doReps(oout, oin, sbuf, trees, 1);      // warmup

        long start = System.currentTimeMillis();
        doReps(oout, oin, sbuf, trees, nbatches);
        return System.currentTimeMillis() - start;
    }

    /**
     * Generate object trees.
     */
    Node[] genTrees(int depth, int ntrees) {
        Node[] trees = new Node[ntrees];
        for (int i = 0; i < ntrees; i++) {
            trees[i] = new Node(null, depth);
        }
        return trees;
    }

    /**
     * Run benchmark for given number of batches, with each batch containing
     * the given number of cycles.
     */
    void doReps(ObjectOutputStream oout, ObjectInputStream oin,
                StreamBuffer sbuf, Node[] trees, int nbatches)
        throws Exception
    {
        int ncycles = trees.length;
        for (int i = 0; i < nbatches; i++) {
            sbuf.reset();
            oout.reset();
            for (int j = 0; j < ncycles; j++) {
                oout.writeObject(trees[j]);
            }
            oout.flush();
            for (int j = 0; j < ncycles; j++) {
                oin.readObject();
            }
        }
    }
}