相关类的代码
public void makeTracks(ArrayList List)
{
Iterator it = List.iterator();//迭代器？
for(int i=0;i<16;i++){
Integer num = (Integer) it.next();
int numKey = num.intValue();
track.add(makeEvent(144,9,numKey,100,i));
track.add(makeEvent(128,9,numKey,100,i+1));
}
}

public void buildTractAndStart() {
ArrayList<Integer> trackList= null;
sequence.deleteTrack(track);
track=sequence.createTrack();
for(int i=0;i<16;i++){
trackList = new ArrayList<Integer>();
for(int j=0;j<16;j++){
JCheckBox jc = (JCheckBox)checkboxList.get(j+(i*16));
if(jc.isSelected()){
int key = instrucment[i];
trackList.add(new Integer(key));
}
else {
trackList.add(null);
}
}
makeTracks(trackList);
}
track.add(makeEvent(192, 9, 1, 0, 15));
try{
sequencer.setSequence(sequence);
sequencer.setLoopCount(sequencer.LOOP_CONTINUOUSLY);
sequencer.start();
sequencer.setTempoInBPM(120);
}catch (Exception e) {
e.printStackTrace();
}
}

用了迭代器就不要用循环

好晕…看不了

简单点试下 Integer num =null;
num.intValue();