Question

Ok, i’m writing a basic game and decided to use MIDI sounds for the fact that they’re tiny compared to MP3. I also decided to use it since Java hosts it’s own API instead of having to use a third-party include.

However, when i’m running a single MIDI file, which usually is around 7000 bytes, my applications free memory is drained so much that it often can pause/interrupt or even throw an exception.

My implementation is;

private class Track {

    private Sequencer sequencer;
    private Sequence sequence;
    private int id;
    private boolean loop;

    public Track(final int id, final byte[] buffer, final boolean loop) throws IOException, InvalidMidiDataException, MidiUnavailableException
    {
        this.id = id;
        this.sequence = MidiSystem.getSequence(new ByteArrayInputStream(buffer));
        this.sequencer = MidiSystem.getSequencer();
        this.loop = loop;
    }

    public synchronized boolean destroy()
    {
        this.id = -1;
        this.sequencer = null;
        this.sequence = null;
        this.loop = false;
        return this.sequencer == null;
    }

    public synchronized boolean play() throws InvalidMidiDataException, MidiUnavailableException
    {
        return play(loop);
    }

    public synchronized boolean play(boolean loop) throws InvalidMidiDataException, MidiUnavailableException
    {
        if(sequencer != null && sequencer.isRunning())
            sequencer.stop();
        sequencer.open();
        sequencer.setSequence(sequence);
        sequencer.setLoopCount(Integer.MAX_VALUE);
        sequencer.start();
        return sequencer.isRunning();
    }

    public synchronized boolean stop()
    {
        if(sequencer != null && sequencer.isRunning())
            sequencer.stop();
        return sequencer != null && !sequencer.isRunning();
    }

    public synchronized boolean playing()
    {
        return sequencer != null && sequencer.isRunning();
    }

}

At the moment I removed everything graphic render related from the application to check that I didn’t have a leak in there, but this was causing the problems.

It’s literally using up over 70MB of Ram just for a 7000 byte file, is that even possible?

To check how much memory is available i’m simply painting;

graphics.drawString("Free: " + Runtime.getRuntime().freeMemory(), 10, 35);

Thanks for any help, will be appreciated.

Answer 1

After looking into it I found out that the ‘close’ method is required to stop memory being used after stopping a synchroniser.