Weird Error

[Nathan Tibbitts]

import javax.sound.*;
public class rand{
	public static void main(String[] args) throws InterruptedException {
		// TODO Auto-generated method stub
		Sequencer player = MidiSystem.getSequencer();
		Sequence seq = new Sequence(timing,4);
		track t = seq.createTrack();
		t.add(myMidiEvent);
		player.setSequence(seq);
				
	}

}

This Java is really weird. My compiler recognizes that Javax.sound is a valid type/object(Not sure which!) The problem is it doesnt recognize Sequencer, Sequence, MidiSystem.getSequencer(). It treats createTrack() as a variable too. Help!

[salvin francis]

Hi Nathan, Welcome to code ranch

I think your program misses a few imports:

import javax.sound.midi.MidiSystem;
import javax.sound.midi.Sequence;
import javax.sound.midi.Sequencer;

what is "track" ? do you mean "javax.sound.midi.Track" ?

[salvin francis]

Your code is missing "timing" and "myMidiEvent" variables. I find "rand" as a very weird name, what does it imply ? Does it have something to do with sound ?
Next time, I suggest you can paste the compile error so that we can help you better.

[Rajith Pemabandu]

suppose using a wild card with a Java import statement is not best practice.  this post  http://www.fredosaurus.com/notes-java/language/10basics/import.html have good explanation of certain options with imports.

[Jesper de Jong]

Welcome to the Ranch.

Note that when you import things with a wildcard *, then you are not importing whatever is in subpackages. So, import javax.sound.* does not import the classes in javax.sound.midi, for example - only classes in the package javax.sound itself.

[Nathan Tibbitts]

I did all the things, now the only error is

Exception in thread "main" javax.sound.midi.InvalidMidiDataException: Unsupported division type: 4.0
	at javax.sound.midi.Sequence.<init>(Sequence.java:154)
	at rand.main(rand.java:14)

[Jesper de Jong]

If you wonder what a specific exception means exactly, then you can lookup its API documentation: javax.sound.midi.InvalidMidiDataException

This is probably happening because the value of the variable timing (the parameter divisionType) in line 6 of your code is not correct:

Sequence seq = new Sequence(timing,4);

The API documentation of the constructor of class Sequence that you are using says:

API documentation wrote:
Constructs a new MIDI sequence with the specified timing division type and timing resolution. The division type must be one of the recognized MIDI timing types.
...
Throws:
InvalidMidiDataException - if divisionType is not valid

This means that the value of the first parameter that you pass to the constructor must be one of the constants declared in class Sequence: PPQ, SMPTE_24, SMPTE_25, SMPTE_30DROP, SMPTE_30

What is the variable timing, and what is its value? You haven't declared it in the code that you posted above, so your code doesn't compile.