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  1. JDK
  2. JDK-4347135

MIDI MetaMessage callback inconsistent

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    • Icon: Bug Bug
    • Resolution: Cannot Reproduce
    • Icon: P4 P4
    • None
    • 1.3.0
    • client-libs



      Name: rlT66838 Date: 06/21/2000


      java version "1.3.0"
      Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0-C)
      Java HotSpot(TM) Client VM (build 1.3.0-C, mixed mode)


      1) I fill a sequence with 100 MetaMessage events, handling meta messages by
      printing a line of text to the screen.

      2) The code below should print the line "got Meta #0" 100 times, once every
      other beat at 100 BPM. The behavior is nondeterministic: sometimes I get one
      callback, maybe 10 seconds from runtime, and other times no callback at all.

      (Apologies for weird cruft, as I have torn this snippet out of a larger code
      base. All I am trying to get here are my callbacks.)

      3) n/a

      4) n/a

      5) SoundBlaster Live, not sure who's synth as I am just requesting the
      MidiSystem.getSequencer().


      ************code:

      import javax.sound.midi.*;
      import java.lang.*;
      import java.util.*;
      import java.io.*;
      import javax.swing.*;
      import java.awt.*;
      import java.awt.event.*;

      class Demo2 {


          static ShortMessage MidiMsg3(int a, int b, int c) {
      try {
      ShortMessage msg = new ShortMessage();
      msg.setMessage((byte)a,(byte)b,(byte)c);
      return msg;
      } catch(InvalidMidiDataException ex) {
      throw new RuntimeException();
      }
          }

          class SequenceImprovisor implements MetaEventListener {
      //Synthesizer synth;
      Instrument[] instruments;
      Sequencer sequencer;
      Sequence sequence;
      Track track;

      SequenceImprovisor() {
      try {

      sequencer=MidiSystem.getSequencer();
      sequence=new Sequence(Sequence.PPQ,10);
      track=sequence.createTrack();
      sequencer.addMetaEventListener(this);

      ShortMessage smsg;

      smsg = MidiMsg3(ShortMessage.NOTE_OFF+0,44,64);
      track.add(new MidiEvent(smsg,10000));
      smsg = MidiMsg3(ShortMessage.NOTE_ON+0,45,64);
      track.add(new MidiEvent(smsg,10));
      smsg = MidiMsg3(ShortMessage.NOTE_OFF+0,45,64);
      track.add(new MidiEvent(smsg,20));

      byte[] data = new byte[1];

      for(int c=0; c<100; c++) {
      MetaMessage meta;
      data[0]=(byte)c;
      meta = new MetaMessage();
      //meta.setMessage(0,data,1); // type, data, length
      track.add(new MidiEvent(meta,c*20));
      }
      sequencer.setSlaveSyncMode(Sequencer.SyncMode.INTERNAL_CLOCK);
      sequencer.setMasterSyncMode(Sequencer.SyncMode.INTERNAL_CLOCK);
      sequencer.open();
      sequencer.setSequence(sequence);
      sequencer.setTempoInBPM(100);
      this.start();
      }
      catch(InvalidMidiDataException ex) {}
      catch(MidiUnavailableException ex) {}
      }
      void start() {sequencer.start();}
      void stop() {sequencer.stop();}

      int noteNum=0;
      void addNote(int pitch) {
      ShortMessage msg;
      byte[] data;

      msg = MidiMsg3(ShortMessage.NOTE_ON+0,pitch,64);
      track.add(new MidiEvent(msg,noteNum*10));

      msg = MidiMsg3(ShortMessage.NOTE_OFF+0,pitch,64);
      track.add(new MidiEvent(msg,noteNum*10+5));

      noteNum++;
      }
      public void meta(MetaMessage msg) {
      byte num=0; //msg.getData()[0];
      System.out.println("got Meta #"+num);
      }
          }


          SequenceImprovisor sequenceImprovisor;

          Demo2() {
      sequenceImprovisor = new SequenceImprovisor();
          }

          public static void main(String[] argv) {
      Demo2 demo2=new Demo2();
          }
      }
      (Review ID: 106361)
      ======================================================================

            fbomerssunw Florian Bomers (Inactive)
            rlewis Roger Lewis (Inactive)
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