- /*
- * @(#)ShortMessage.java 1.24 03/12/19
- *
- * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
- package javax.sound.midi;
-
- /**
- * A <code>ShortMessage</code> contains a MIDI message that has at most
- * two data bytes following its status byte. The types of MIDI message
- * that satisfy this criterion are channel voice, channel mode, system common,
- * and system real-time--in other words, everything except system exclusive
- * and meta-events. The <code>ShortMessage</code> class provides methods
- * for getting and setting the contents of the MIDI message.
- * <p>
- * A number of <code>ShortMessage</code> methods have integer parameters by which
- * you specify a MIDI status or data byte. If you know the numeric value, you
- * can express it directly. For system common and system real-time messages,
- * you can often use the corresponding fields of <code>ShortMessage</code>, such as
- * {@link #SYSTEM_RESET SYSTEM_RESET}. For channel messages,
- * the upper four bits of the status byte are specified by a command value and
- * the lower four bits are specified by a MIDI channel number. To
- * convert incoming MIDI data bytes that are in the form of Java's signed bytes,
- * you can use the <A HREF="MidiMessage.html#integersVsBytes">conversion code</A>
- * given in the <code>{@link MidiMessage}</code> class description.
- *
- * @see SysexMessage
- * @see MetaMessage
- *
- * @version 1.24, 03/12/19
- * @author David Rivas
- * @author Kara Kytle
- * @author Florian Bomers
- */
-
- public class ShortMessage extends MidiMessage {
-
-
- // Status byte defines
-
-
- // System common messages
-
- /**
- * Status byte for MIDI Time Code Quarter Frame message (0xF1, or 241).
- * @see MidiMessage#getStatus
- */
- public static final int MIDI_TIME_CODE = 0xF1; // 241
-
- /**
- * Status byte for Song Position Pointer message (0xF2, or 242).
- * @see MidiMessage#getStatus
- */
- public static final int SONG_POSITION_POINTER = 0xF2; // 242
-
- /**
- * Status byte for MIDI Song Select message (0xF3, or 243).
- * @see MidiMessage#getStatus
- */
- public static final int SONG_SELECT = 0xF3; // 243
-
- /**
- * Status byte for Tune Request message (0xF6, or 246).
- * @see MidiMessage#getStatus
- */
- public static final int TUNE_REQUEST = 0xF6; // 246
-
- /**
- * Status byte for End of System Exclusive message (0xF7, or 247).
- * @see MidiMessage#getStatus
- */
- public static final int END_OF_EXCLUSIVE = 0xF7; // 247
-
-
- // System real-time messages
-
- /**
- * Status byte for Timing Clock messagem (0xF8, or 248).
- * @see MidiMessage#getStatus
- */
- public static final int TIMING_CLOCK = 0xF8; // 248
-
- /**
- * Status byte for Start message (0xFA, or 250).
- * @see MidiMessage#getStatus
- */
- public static final int START = 0xFA; // 250
-
- /**
- * Status byte for Continue message (0xFB, or 251).
- * @see MidiMessage#getStatus
- */
- public static final int CONTINUE = 0xFB; // 251
-
- /**
- * Status byte for Stop message (0xFC, or 252).
- * @see MidiMessage#getStatus
- */
- public static final int STOP = 0xFC; //252
-
- /**
- * Status byte for Active Sensing message (0xFE, or 254).
- * @see MidiMessage#getStatus
- */
- public static final int ACTIVE_SENSING = 0xFE; // 254
-
- /**
- * Status byte for System Reset message (0xFF, or 255).
- * @see MidiMessage#getStatus
- */
- public static final int SYSTEM_RESET = 0xFF; // 255
-
-
- // Channel voice message upper nibble defines
-
- /**
- * Command value for Note Off message (0x80, or 128)
- */
- public static final int NOTE_OFF = 0x80; // 128
-
- /**
- * Command value for Note On message (0x90, or 144)
- */
- public static final int NOTE_ON = 0x90; // 144
-
- /**
- * Command value for Polyphonic Key Pressure (Aftertouch) message (0xA0, or 128)
- */
- public static final int POLY_PRESSURE = 0xA0; // 160
-
- /**
- * Command value for Control Change message (0xB0, or 176)
- */
- public static final int CONTROL_CHANGE = 0xB0; // 176
-
- /**
- * Command value for Program Change message (0xC0, or 192)
- */
- public static final int PROGRAM_CHANGE = 0xC0; // 192
-
- /**
- * Command value for Channel Pressure (Aftertouch) message (0xD0, or 208)
- */
- public static final int CHANNEL_PRESSURE = 0xD0; // 208
-
- /**
- * Command value for Pitch Bend message (0xE0, or 224)
- */
- public static final int PITCH_BEND = 0xE0; // 224
-
-
- // Instance variables
-
- /**
- * Constructs a new <code>ShortMessage</code>. The
- * contents of the new message are guaranteed to specify
- * a valid MIDI message. Subsequently, you may set the
- * contents of the message using one of the <code>setMessage</code>
- * methods.
- * @see #setMessage
- */
- public ShortMessage() {
- this(new byte[3]);
- // Default message data: NOTE_ON on Channel 0 with max volume
- data[0] = (byte) (NOTE_ON & 0xFF);
- data[1] = (byte) 64;
- data[2] = (byte) 127;
- length = 3;
- }
-
-
- /**
- * Constructs a new <code>ShortMessage</code>.
- * @param data an array of bytes containing the complete message.
- * The message data may be changed using the <code>setMessage</code>
- * method.
- * @see #setMessage
- */
- // $$fb this should throw an Exception in case of an illegal message!
- protected ShortMessage(byte[] data) {
- // $$fb this may set an invalid message.
- // Can't correct without compromising compatibility
- super(data);
- }
-
-
- /**
- * Sets the parameters for a MIDI message that takes no data bytes.
- * @param status the MIDI status byte
- * @throws <code>InvalidMidiDataException</code> if <code>status</code> does not
- * specify a valid MIDI status byte for a message that requires no data bytes.
- * @see #setMessage(int, int, int)
- * @see #setMessage(int, int, int, int)
- */
- public void setMessage(int status) throws InvalidMidiDataException {
- // check for valid values
- int dataLength = getDataLength(status); // can throw InvalidMidiDataException
- if (dataLength != 0) {
- throw new InvalidMidiDataException("Status byte; " + status + " requires " + dataLength + " data bytes");
- }
- setMessage(status, 0, 0);
- }
-
-
- /**
- * Sets the parameters for a MIDI message that takes one or two data
- * bytes. If the message takes only one data byte, the second data
- * byte is ignored; if the message does not take any data bytes, both
- * data bytes are ignored.
- *
- * @param status the MIDI status byte
- * @param data1 the first data byte
- * @param data2 the second data byte
- * @throws <code>InvalidMidiDataException</code> if the
- * the status byte, or all data bytes belonging to the message, do
- * not specify a valid MIDI message.
- * @see #setMessage(int, int, int, int)
- * @see #setMessage(int)
- */
- public void setMessage(int status, int data1, int data2) throws InvalidMidiDataException {
- // check for valid values
- int dataLength = getDataLength(status); // can throw InvalidMidiDataException
- if (dataLength > 0) {
- if (data1 < 0 || data1 > 127) {
- throw new InvalidMidiDataException("data1 out of range: " + data1);
- }
- if (dataLength > 1) {
- if (data2 < 0 || data2 > 127) {
- throw new InvalidMidiDataException("data2 out of range: " + data2);
- }
- }
- }
-
-
- // set the length
- length = dataLength + 1;
- // re-allocate array if ShortMessage(byte[]) constructor gave array with fewer elements
- if (data == null || data.length < length) {
- data = new byte[3];
- }
-
- // set the data
- data[0] = (byte) (status & 0xFF);
- if (length > 1) {
- data[1] = (byte) (data1 & 0xFF);
- if (length > 2) {
- data[2] = (byte) (data2 & 0xFF);
- }
- }
- }
-
-
- /**
- * Sets the short message parameters for a channel message
- * which takes up to two data bytes. If the message only
- * takes one data byte, the second data byte is ignored; if
- * the message does not take any data bytes, both data bytes
- * are ignored.
- *
- * @param command the MIDI command represented by this message
- * @param channel the channel associated with the message
- * @param data1 the first data byte
- * @param data2 the second data byte
- * @throws <code>InvalidMidiDataException</code> if the
- * status byte or all data bytes belonging to the message, do
- * not specify a valid MIDI message
- *
- * @see #setMessage(int, int, int)
- * @see #setMessage(int)
- * @see #getCommand
- * @see #getChannel
- * @see #getData1
- * @see #getData2
- */
- public void setMessage(int command, int channel, int data1, int data2) throws InvalidMidiDataException {
- // check for valid values
- if (command >= 0xF0 || command < 0x80) {
- throw new InvalidMidiDataException("command out of range: 0x" + Integer.toHexString(command));
- }
- if ((channel & 0xFFFFFFF0) != 0) { // <=> (channel<0 || channel>15)
- throw new InvalidMidiDataException("channel out of range: " + channel);
- }
- setMessage((command & 0xF0) | (channel & 0x0F), data1, data2);
- }
-
-
- /**
- * Obtains the MIDI channel associated with this event. This method
- * assumes that the event is a MIDI channel message; if not, the return
- * value will not be meaningful.
- * @return MIDI channel associated with the message.
- * @see #setMessage(int, int, int, int)
- */
- public int getChannel() {
- // this returns 0 if an invalid message is set
- return (getStatus() & 0x0F);
- }
-
-
- /**
- * Obtains the MIDI command associated with this event. This method
- * assumes that the event is a MIDI channel message; if not, the return
- * value will not be meaningful.
- * @see #setMessage(int, int, int, int)
- */
- public int getCommand() {
- // this returns 0 if an invalid message is set
- return (getStatus() & 0xF0);
- }
-
-
- /**
- * Obtains the first data byte in the message.
- * @return the value of the <code>data1</code> field
- * @see #setMessage(int, int, int)
- */
- public int getData1() {
- if (length > 1) {
- return (data[1] & 0xFF);
- }
- return 0;
- }
-
-
- /**
- * Obtains the second data byte in the message.
- * @return the value of the <code>data2</code> field
- * @see #setMessage(int, int, int)
- */
- public int getData2() {
- if (length > 2) {
- return (data[2] & 0xFF);
- }
- return 0;
- }
-
-
- /**
- * Creates a new object of the same class and with the same contents
- * as this object.
- * @return a clone of this instance.
- */
- public Object clone() {
- byte[] newData = new byte[length];
- System.arraycopy(data, 0, newData, 0, newData.length);
-
- ShortMessage msg = new ShortMessage(newData);
- return msg;
- }
-
-
- /**
- * Retrieves the number of data bytes associated with a particular
- * status byte value.
- * @param status status byte value, which must represent a short MIDI message
- * @return data length in bytes (0, 1, or 2)
- * @throws <code>InvalidMidiDataException</code> if the
- * <code>status</code> argument does not represent the status byte for any
- * short message
- */
- protected final int getDataLength(int status) throws InvalidMidiDataException {
- // system common and system real-time messages
- switch(status) {
- case 0xF6: // Tune Request
- case 0xF7: // EOX
- // System real-time messages
- case 0xF8: // Timing Clock
- case 0xF9: // Undefined
- case 0xFA: // Start
- case 0xFB: // Continue
- case 0xFC: // Stop
- case 0xFD: // Undefined
- case 0xFE: // Active Sensing
- case 0xFF: // System Reset
- return 0;
- case 0xF1: // MTC Quarter Frame
- case 0xF3: // Song Select
- return 1;
- case 0xF2: // Song Position Pointer
- return 2;
- default:
- }
-
- // channel voice and mode messages
- switch(status & 0xF0) {
- case 0x80:
- case 0x90:
- case 0xA0:
- case 0xB0:
- case 0xE0:
- return 2;
- case 0xC0:
- case 0xD0:
- return 1;
- default:
- throw new InvalidMidiDataException("Invalid status byte: " + status);
- }
- }
- }