Java MidiMessage.getLength方法代碼示例

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/** parses this message for a META tempo message and returns
 * the tempo in MPQ, or -1 if this isn't a tempo message
 */
public static int getTempoMPQ(MidiMessage midiMsg) {
    // first check if it is a META message at all
    if (midiMsg.getLength() != 6
        || midiMsg.getStatus() != MetaMessage.META) {
        return -1;
    }
    byte[] msg = midiMsg.getMessage();
    if (((msg[1] & 0xFF) != META_TEMPO_TYPE) || (msg[2] != 3)) {
        return -1;
    }
    int tempo =    (msg[5] & 0xFF)
                | ((msg[4] & 0xFF) << 8)
                | ((msg[3] & 0xFF) << 16);
    return tempo;
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/** return true if the passed message is Meta End Of Track */
public static boolean isMetaEndOfTrack(MidiMessage midiMsg) {
    // first check if it is a META message at all
    if (midiMsg.getLength() != 3
        || midiMsg.getStatus() != MetaMessage.META) {
        return false;
    }
    // now get message and check for end of track
    byte[] msg = midiMsg.getMessage();
    return ((msg[1] & 0xFF) == META_END_OF_TRACK_TYPE) && (msg[2] == 0);
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/** return if the given message is a meta tempo message */
public static boolean isMetaTempo(MidiMessage midiMsg) {
    // first check if it is a META message at all
    if (midiMsg.getLength() != 6
        || midiMsg.getStatus() != MetaMessage.META) {
        return false;
    }
    // now get message and check for tempo
    byte[] msg = midiMsg.getMessage();
    // meta type must be 0x51, and data length must be 3
    return ((msg[1] & 0xFF) == META_TEMPO_TYPE) && (msg[2] == 3);
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
private static boolean messagesEqual(MidiMessage m1, MidiMessage m2) {
    if (m1 == null || m2 == null) {
        return false;
    }
    if (m1.getLength() != m2.getLength()) {
        return false;
    }
    byte[] array1 = m1.getMessage();
    byte[] array2 = m2.getMessage();
    return messagesEqual(array1, array2);
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
static public Polylist midiMessage2polylist(MidiMessage message)
{
  byte[] data = message.getMessage();
  int messageLength = message.getLength();
  PolylistBuffer buffer = new PolylistBuffer();
  // getStatus() returns status as an integer rather than byte.
  // As status is the first byte in the array, it is skipped below.
  buffer.append("message");
  for( int i = 1; i < messageLength; i++ )
    {
      buffer.append(data[i]);
    }
return buffer.toPolylist();
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/**
 * Set the first data byte of a 2 or 3 byte MidiMessage. 
 */
static public MidiMessage setData1(MidiMessage msg, int data1)
	throws InvalidMidiDataException {
    if ( msg.getLength() == 1 )
        throw new InvalidMidiDataException("Can't setData1 on 1 byte message");
 ((ShortMessage)msg).setMessage(getStatus(msg), data1, getData2(msg));
    return msg;
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/**
   * Set the second data byte of a 3 byte MidiMessage. 
   */
  static public MidiMessage setData2(MidiMessage msg, int data2)
  	throws InvalidMidiDataException {
if ( msg.getLength() != 3 )
          throw new InvalidMidiDataException("Can't setData2 on "+msg.getLength()+" byte message");
      ((ShortMessage)msg).setMessage(getStatus(msg), getData1(msg), data2);
      return msg;
  }
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/** Determine if the given message is a channel volume change.
 *
 * @return Channel number for which volume is being changed, or -1 if not a
 * channel volume change command.
 */
private int getVolumeChangeChannel(MidiMessage message) {
    if (message.getLength() >= 3) {
        byte[] mBytes = message.getMessage();
        if ((byte) 0xb0 <= mBytes[0] && mBytes[0] < (byte) 0xc0 &&
            mBytes[1] == 7) {
            return mBytes[0] & 15;
        }
    }
    return -1;
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
/**
 * chase all events from beginning of Track
 * and send note off for those events that are active
 * in noteOnCache array.
 * It is possible, of course, to catch notes from other tracks,
 * but better than more complicated logic to detect
 * which notes are really from this track
 */
private void sendNoteOffIfOn(Track track, long endTick) {
    int size = track.size();
    int done = 0;
    try {
        for (int i = 0; i < size; i++) {
            MidiEvent event = track.get(i);
            if (event.getTick() > endTick) break;
            MidiMessage msg = event.getMessage();
            int status = msg.getStatus();
            int len = msg.getLength();
            if (len == 3 && ((status & 0xF0) == ShortMessage.NOTE_ON)) {
                int note = -1;
                if (msg instanceof ShortMessage) {
                    ShortMessage smsg = (ShortMessage) msg;
                    if (smsg.getData2() > 0) {
                        // only consider Note On with velocity > 0
                        note = smsg.getData1();
                    }
                } else {
                    byte[] data = msg.getMessage();
                    if ((data[2] & 0x7F) > 0) {
                        // only consider Note On with velocity > 0
                        note = data[1] & 0x7F;
                    }
                }
                if (note >= 0) {
                    int bit = 1<<(status & 0x0F);
                    if ((noteOnCache[note] & bit) != 0) {
                        // the bit is set. Send Note Off
                        getTransmitterList().sendMessage(status | (note<<8), -1);
                        // clear the bit
                        noteOnCache[note] &= (0xFFFF ^ bit);
                        done++;
                    }
                }
            }
        }
    } catch (ArrayIndexOutOfBoundsException aioobe) {
        // this happens when messages are removed
        // from the track while this method executes
    }
    if (DEBUG_PUMP) Printer.println("  sendNoteOffIfOn: sent "+done+" messages.");
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
private static boolean testMessage(MidiMessage message) {
    receivedMessage = null;
    baos = new ByteArrayOutputStream();
    expectedBytes = message.getLength();
    receivedBytes = 0;
    System.out.print("Sending message " + getMessageString(message.getMessage())+"...");
    receiver.send(message, -1);
    /* sending 3 bytes can roughly be done in 1 millisecond,
     * so this estimate waits at max 3 times longer than the message takes,
     * plus a little offset to allow the MIDI subsystem some processing time
     */
    int offset = 300; // standard offset 100 millis
    if (message instanceof SysexMessage) {
        // add a little processing time to sysex messages
        offset += 1000;
    }
    if (receivedBytes < expectedBytes) {
        sleep(expectedBytes + offset);
    }
    boolean equal;
    byte[] data = baos.toByteArray();
    if (data.length > 0) {
        equal = messagesEqual(message.getMessage(), data);
    } else {
        equal = messagesEqual(message, receivedMessage);
        if (receivedMessage != null) {
            data = receivedMessage.getMessage();
        } else {
            data = null;
        }
    }
    if (!equal) {
        if ((message.getStatus() & 0xF0) == ShortMessage.PITCH_BEND) {
            out("NOT failed (may expose a bug in ALSA)");
            equal = true;
            sleep(100);
        }
        if ((message.getStatus() == 0xF6) && (message.getLength() == 1)) {
            out("NOT failed (may expose an issue on Solaris)");
            equal = true;
            sleep(100);
        }
        else if ((message.getStatus()) == 0xF0 && message.getLength() < 4) {
            out("NOT failed (not a correct sys ex message)");
            equal = true;
            sleep(200);
        } else {
            out("FAILED:");
            out("  received as " + getMessageString(data));
        }
    } else {
        System.out.println("OK");
    }
    return equal;
}
 

import javax.sound.midi.MidiMessage; //導入方法依賴的package包/類
public static int getLength(MidiMessage msg) {
    return msg.getLength();
}