Java MIDI - ControllerEventListener（如何更改乐器）

Posted 2023-02-16

【中文标题】Java MIDI - ControllerEventListener（如何更改乐器）

【英文标题】：Java MIDI - ControllerEventListener (How to change the instrument)

【发布时间】：2019-03-18 18:53:41

【问题描述】：

我正在开发一个生成和播放 MIDI 事件的程序。我已经实现了 ControllerEventListener 接口，因为我想在每次播放 15 个音符中的一个时打印消息。

问题是，我不能再改变演奏音符的乐器（我不得不说我的电脑不使用默认钢琴，但如果我添加了鼓或类似的东西ControllerEvent to the track）我已经在 J​​ava API 规范中查找了涉及的方法，但是我没有找到可以解决我的问题的方法，就像我在这个站点上或通过谷歌搜索找到的一样少。 我也做了，是尝试改变整个频道的乐器（通过添加一个 Program Change 消息），但它和以前一样。

代码如下：

import javax.sound.midi.*;

public class MusikPlayer implements ControllerEventListener 
    public static void main(String[] args) 
        MusikPlayer mini = new MusikPlayer();
        mini.go();
    

    public void go() 
        try 
            Sequencer sequencer = MidiSystem.getSequencer();
            sequencer.open();

            int[] wishedEvents = 127;
            sequencer.addControllerEventListener(this, wishedEvents);

            Sequence seq = new Sequence(Sequence.PPQ, 4);
            Track track = seq.createTrack();

            for (int i = 5; i < 61; i+=4) 
                track.add(generateEvent(144, 1, i, 100, i));
                track.add(generateEvent(128, 1, i, 100, i+2));
                track.add(generateEvent(176, 1, 127, 0, i));
            

            sequencer.setSequence(seq);
            sequencer.setTempoInBPM(220);
            sequencer.start();
            Thread.sleep(5000);
            sequencer.close();

         catch (Exception e) e.printStackTrace();
    

    public void controlChange(ShortMessage event) 
        System.out.println("la");
    

    public MidiEvent generateEvent(int comd, int chan, int one, int two, int tick) 
        MidiEvent event = null;

        try 
            ShortMessage a = new ShortMessage();
            a.setMessage(comd, chan, one, two);
            event = new MidiEvent(a, tick);
         catch (Exception e) 

        return event;
    

我现在的问题是：如何在不更改事件处理程序的情况下更改仪器？

【参考方案1】：

检查此代码

import java.io.*;
import java.text.SimpleDateFormat;
import java.util.*;
import javax.sound.midi.*;

public class TestMidi 

  private static final int TYPE_SINGLE_TRACK = 0;
  private static final int TYPE_PARALLEL_TRACKS = 1;
  private static final int TYPE_SERIAL_TRACKS = 2;

  public static void main(String[] args) 

    String filename = TestMidi.class.getName() + "_" + new SimpleDateFormat("yyyyMMdd-HHmmss.SSSS").format(new Date()) + ".mid";
    System.out.println("filename:" + filename);
    File midiOutputFile = new File(filename);
    System.out.println("midiOutputFile.getAbsolutePath():" + midiOutputFile.getAbsolutePath());
    Sequence sequence = null;
    Synthesizer synthesizer = null;
    final Sequencer sequencer;
    List<Instrument> listInstrument;
    List<MidiChannel> listMidiChannel;
    Track trackPiano;
    Track trackViolin;
    try 
      synthesizer = MidiSystem.getSynthesizer();
      synthesizer.open();
      synthesizer.loadAllInstruments(synthesizer.getDefaultSoundbank());
      listInstrument = Arrays.asList(synthesizer.getLoadedInstruments());
      listMidiChannel = Arrays.asList(synthesizer.getChannels());
      listInstrument
          .stream()
          .map(instrument -> instrument.getPatch())
          .forEach(patch -> System.out.println("patch.getBank():" + patch.getBank()
          + "\tpatch.getProgram():" + patch.getProgram()
          + "\tlistInstrument.get(patch.getProgram()).getName():" + listInstrument.get(patch.getProgram()).getName()));

      Instrument instrumentPiano = listInstrument
          .stream()
          .filter(instrument -> instrument.getName().equals("Acoustic Grand Piano"))
          .findFirst()
          .get();
      Instrument instrumentViolin = listInstrument
          .stream()
          .filter(instrument -> instrument.getName().equals("Violin"))
          .findFirst()
          .get();

      int channelPiano = 0;
      int channelViolin = 1;

      listMidiChannel.get(channelPiano).programChange(instrumentPiano.getPatch().getProgram());
      listMidiChannel.get(channelViolin).programChange(instrumentViolin.getPatch().getProgram());

      sequence = new Sequence(Sequence.PPQ, 10); //10 pulses per quarter note
      trackPiano = sequence.createTrack();
      trackViolin = sequence.createTrack();
      long instant = 0L;
      trackPiano.add(createMidiEvent(ShortMessage.PROGRAM_CHANGE, channelPiano, instrumentPiano.getPatch().getProgram(), 0, instant * sequence.getResolution() / 500));
      trackViolin.add(createMidiEvent(ShortMessage.PROGRAM_CHANGE, channelViolin, instrumentViolin.getPatch().getProgram(), 0, instant * sequence.getResolution() / 500));

      instant = 250L; //250milliSeconds -> 1/4 Second
      int pitchViolin = 63;
      int valueViolin = 127;
      trackViolin.add(createMidiEvent(ShortMessage.NOTE_ON, channelViolin, pitchViolin, valueViolin, instant * sequence.getResolution() / 500));
      instant = 500L; //500milliSeconds -> 1/2 Second
      int pitchPiano = 60;
      int valuePiano = 64;
      trackPiano.add(createMidiEvent(ShortMessage.NOTE_ON, channelPiano, pitchPiano, valuePiano, instant * sequence.getResolution() / 500));
      instant = 1000L; //1000milliSeconds -> 1 Second
      trackPiano.add(createMidiEvent(ShortMessage.NOTE_OFF, channelPiano, pitchPiano, valuePiano, instant * sequence.getResolution() / 500));
      instant = 1250L; //1250milliSeconds

      trackViolin.add(createMidiEvent(ShortMessage.NOTE_OFF, channelViolin, pitchViolin, valueViolin, instant * sequence.getResolution() / 500));

      instant = 1500L; //1500milliSeconds
      pitchPiano = 66;
      trackPiano.add(createMidiEvent(ShortMessage.NOTE_ON, channelPiano, pitchPiano, valuePiano, instant * sequence.getResolution() / 500));
      instant = 1000L; //500milliSeconds
      trackPiano.add(createMidiEvent(ShortMessage.NOTE_OFF, channelPiano, pitchPiano, valuePiano, instant * sequence.getResolution() / 500));

      sequencer = MidiSystem.getSequencer();
      try 
        sequencer.open();
        sequencer.setSequence(sequence);
       catch (Exception ex) 
        Logger.getLogger(TestMidi.class.getName()).log(Level.SEVERE, null, ex);
      
      sequencer.start();

      Integer midiFileType;
      if (sequence.getTracks().length == 1) 
        midiFileType = TYPE_SINGLE_TRACK;
       else 
        midiFileType = TYPE_PARALLEL_TRACKS;
      

      int[] arrayMidiFileTypes = MidiSystem.getMidiFileTypes(sequence);
      if (arrayMidiFileTypes.length > 0) 
        MidiSystem.write(sequence, arrayMidiFileTypes[0], midiOutputFile);
      

      sequencer.addMetaEventListener(new MetaEventListener() 
        @Override
        public void meta(MetaMessage metaMsg) 
          if (metaMsg.getType() == 0x2F) 
            sequencer.close();
          
        
      );

      /*
      while (sequencer.isRunning()) 
        try 
          Thread.sleep(100);
         catch (InterruptedException ex) 
          Logger.getLogger(TestMidi.class.getName()).log(Level.SEVERE, null, ex);
        
      
      sequencer.close();
       */
     catch (InvalidMidiDataException e) 
      Logger.getLogger(TestMidi.class.getName()).log(Level.SEVERE, null, e);

     catch (MidiUnavailableException ex) 
      Logger.getLogger(TestMidi.class.getName()).log(Level.SEVERE, null, ex);
     catch (IOException ex) 
      Logger.getLogger(TestMidi.class.getName()).log(Level.SEVERE, null, ex);
    
  

  private static MidiEvent createMidiEvent(int command, int channel, int data1, int data2, long instant) 
    ShortMessage shortMessage = new ShortMessage();
    try 
      shortMessage.setMessage(
          command,
          channel,
          data1,
          data2);
     catch (InvalidMidiDataException e) 
    
    return new MidiEvent(shortMessage, instant);