net.sf.jack4j
Class JackMidiPortBuffer

java.lang.Object
  net.sf.jack4j.JackMidiPortBuffer

public class JackMidiPortBuffer
extends java.lang.Object

MIDI buffer for JackLocalMidiPort.

The instance may be obtained with JackLocalMidiPort.initializeMidiBuffer(int), and is only valid during the current process cycle.

Constructor Summary

JackMidiPortBuffer(long bufferPointer)

Method Summary

void	clearBuffer() Clears an event buffer.
long	eventReserve(int time, int dataSize) Allocate space for an event to be written to an event port buffer.
void	eventWrite(int time, byte[] data) Write an event into an event port buffer.
long	getBufferPointer() Native pointer to buffer data.
JackMidiEvent	getEvent(int index) Returns MIDI event from the (input) buffer.
int	getEventCount() Returns current number of MIDI events in the buffer.
int	getLostEventsCount() Returns the number of events that could not be written to port.
int	getMaxEventSize() Returns the size of the largest event that can be stored by the port.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JackMidiPortBuffer

public JackMidiPortBuffer(long bufferPointer)

Method Detail

getBufferPointer

public long getBufferPointer()

Native pointer to buffer data.

The pointer is packed as long value.

getEventCount

public int getEventCount()

Returns current number of MIDI events in the buffer.

getEvent

public JackMidiEvent getEvent(int index)
                       throws JackException

Returns MIDI event from the (input) buffer.

Parameters:

index - event number, must be non-negative and lower than getEventCount()

Returns:

the event

Throws:

JackException - if native Jack API fails

clearBuffer

public void clearBuffer()

Clears an event buffer.

May be called only during client's process callback.

This should be called at the beginning of each process cycle before calling eventReserve(int, int) or eventWrite(int, byte[]). This function may not be called on an input port.

eventReserve

public long eventReserve(int time,
                         int dataSize)
                  throws JackException

Allocate space for an event to be written to an event port buffer.

May be called only during client's process callback.

There's probably no good reason to use this method in Java; use eventWrite(int, byte[]) instead.

The returned value is a native pointer of type jack_midi_data_t*. packed as long.

Clients are to write the actual event data to be written starting at the pointer returned by this function. Clients must not write more than dataSize bytes into this buffer. Clients must write normalized MIDI data to the port - no running status and no (1-byte) realtime messages interspersed with other messages (realtime messages are fine when they occur on their own, like other messages).

Parameters:

time - sample offset of the event (number of frames since cycle start)

dataSize - length of event's raw data in bytes

Returns:

jack_midi_data_t* packed as long

Throws:

JackException - if the error occurrs (native function jack_midi_event_reserve returns NULL)

eventWrite

public void eventWrite(int time,
                       byte[] data)
                throws JackException

Write an event into an event port buffer.

May be called only during client's process callback.

The data must be normalized MIDI data - no running status and no (1-byte) realtime messages interspersed with other messages (realtime messages are fine when they occur on their own, like other messages).

Parameters:

time - sample offset of the event (number of frames since cycle start)

data - raw MIDI data

Throws:

JackException - if error occurrs

getMaxEventSize

public int getMaxEventSize()

Returns the size of the largest event that can be stored by the port.

May be called only during client's process callback.

getLostEventsCount

public int getLostEventsCount()

Returns the number of events that could not be written to port.