Introduction


JRtMidi is a Java wrapper for the RtMidi library.

For more information on RtMidi, please see the documentation included in the RtMidi subdirectory.  Or go to http://www.music.mcgill.ca/~gary/rtmidi/



Building


JRtMidi requires ANT, SCons and SWIG to build:

ANT - http://ant.apache.org
SCons - http://www.scons.org
SWIG - http://www.swig.org

To build the complete distribution, including Jar and library type 'ant'.  This will generate the wrappers, build the library, compile the class files, create a jar file, then put the Jar and the library into the 'dist' folder.

To test the implementation using virtual ports type 'ant test'. Note; you will need to connect the virtual ports by hand. For example, in Linux: 
	'aconnect 129 130' 
will connect client 129 to 130.

If you would like to build JRtMidi with a newer version of RtMidi you will need to change the RT_MIDI_FOLDER variable in the SConstruct file, and update the 'rtmidi.version' variable in build.xml



Usage


To see an example of it's usage, check out 'jtest/VirtualPortInOutTest.java'.   

To send a MIDI message you will need to do something like:

'MySender.java':

	class MySender {
		public static void main(String[] args) {
			System.loadLibrary("jrtmidi");
			RtMidiOut output = new RtMidiOut("My Input Client");
			CharVector vector = new CharVector(3);
			vector.set(0,(short)144); //'note on, channel 1' MIDI status byte
			vector.set(1,(short)90); //note
			vector.set(2,(short)66); //velocity
			input.openVirtualPort("foooz");
			input.sendMessage(vector);
		}
	}


To receive a messages, you *should* use a callback (rather than polling with 'getMessage()'):

'MyCallback.java':

	import org.rtmidi.RtCallback;
	import org.rtmidi.CharVector;

	class MyCallback extends RtCallback {
		public void receiveMessage(double timeStamp, CharVector message) {
			String str = "";
			for (int i = 0; i < message.size(); i++) {
				if (i != 0) str += ", ";
				str += message.get(i);
			}
			System.out.println("Received: " + str);
		}
	}

'MyReceiver.java':

	import org.rtmidi.*;

	class MyReceiver {
		public static void main(String[] args) {
			System.loadLibrary("jrtmidi");
			RtMidiIn input = new RtMidiIn("My Input");
			input.setCallback( new MyCallback() );
			input.openVirtualPort();	
		}
	}

NOTE:  'libjrtmidi.so' must be in one of library paths! These paths are different from class paths.  You can make sure it is by exporting the environment variable LD_LIBRARY_PATH to a path which contains libjrtmidi.so.  This is kind of awkward; I'm sure there is a way to automate this.