EncoderThread.java

// EncoderThread.java -- run LZMA encoder in a separate thread
// Copyright (c)2007 Christopher League <league@contrapunctus.net>

// This is free software, but it comes with ABSOLUTELY NO WARRANTY.
// GNU Lesser General Public License 2.1 or Common Public License 1.0

package net.contrapunctus.lzma;

import SevenZip.Compression.LZMA.Encoder;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.util.concurrent.ArrayBlockingQueue;

class EncoderThread extends Thread
{
    public static final Integer DEFAULT_DICT_SZ_POW2 = new Integer(20);
    protected ArrayBlockingQueue<byte[]> q;
    protected InputStream in;
    protected OutputStream out;
    protected Encoder enc;
    protected IOException exn;

    private static final PrintStream dbg = System.err;
    private static final boolean DEBUG;

    static {
        String ds = null;
        try { ds = System.getProperty("DEBUG_LzmaCoders"); }
        catch(SecurityException e) { }
        DEBUG = ds != null;
    }

    /**
     * @param dictSzPow2 If non-null, equivalent to the N in the -dN arg to LzmaAlone
     * @param fastBytes  If non-null, equivalent to the N in the -fbN arg to LzmaAlone
     */
    EncoderThread( OutputStream _out, Integer dictSzPow2, Integer fastBytes)
    {
        q = ConcurrentBufferOutputStream.newQueue();
        in = ConcurrentBufferInputStream.create( q );
        out = _out;
        enc = new Encoder();
        exn = null;
        enc.SetDictionarySize(1 << (dictSzPow2 == null ? DEFAULT_DICT_SZ_POW2 : dictSzPow2).intValue());
        if (fastBytes != null)
            enc.SetNumFastBytes(fastBytes.intValue());
        if(DEBUG) dbg.printf("%s << %s (%s)%n", this, in, q);
    }

    public void run( )
    {
        try {
            enc.SetEndMarkerMode( true );
            if( LzmaOutputStream.LZMA_HEADER ) {
                enc.WriteCoderProperties( out );
                // 5d 00 00 10 00
                long fileSize = -1;
                for (int i = 0; i < 8; i++)
                    out.write((int)(fileSize >>> (8 * i)) & 0xFF);
            }
            if(DEBUG) dbg.printf("%s begins%n", this);
            enc.Code( in, out, -1, -1, null );
            if(DEBUG) dbg.printf("%s ends%n", this);
            out.close( );
        }
        catch( IOException _exn ) {
            exn = _exn;
            if(DEBUG) dbg.printf("%s exception: %s%n", exn.getMessage());
        }
    }

    public String toString( )
    {
        return String.format("Enc@%x", hashCode());
    }
}