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	/*
	* Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package javax.sound.midi;

	/**
	* A <code>SysexMessage</code> object represents a MIDI system exclusive message.
	* <p>
	* When a system exclusive message is read from a MIDI file, it always has
	* a defined length. Data from a system exclusive message from a MIDI file
	* should be stored in the data array of a <code>SysexMessage</code> as
	* follows: the system exclusive message status byte (0xF0 or 0xF7), all
	* message data bytes, and finally the end-of-exclusive flag (0xF7).
	* The length reported by the <code>SysexMessage</code> object is therefore
	* the length of the system exclusive data plus two: one byte for the status
	* byte and one for the end-of-exclusive flag.
	* <p>
	* As dictated by the Standard MIDI Files specification, two status byte values are legal
	* for a <code>SysexMessage</code> read from a MIDI file:
	* <ul>
	* <li>0xF0: System Exclusive message (same as in MIDI wire protocol)</li>
	* <li>0xF7: Special System Exclusive message</li>
	* </ul>
	* <p>
	* When Java Sound is used to handle system exclusive data that is being received
	* using MIDI wire protocol, it should place the data in one or more
	* <code>SysexMessages</code>. In this case, the length of the system exclusive data
	* is not known in advance; the end of the system exclusive data is marked by an
	* end-of-exclusive flag (0xF7) in the MIDI wire byte stream.
	* <ul>
	* <li>0xF0: System Exclusive message (same as in MIDI wire protocol)</li>
	* <li>0xF7: End of Exclusive (EOX)</li>
	* </ul>
	* The first <code>SysexMessage</code> object containing data for a particular system
	* exclusive message should have the status value 0xF0. If this message contains all
	* the system exclusive data
	* for the message, it should end with the status byte 0xF7 (EOX).
	* Otherwise, additional system exclusive data should be sent in one or more
	* <code>SysexMessages</code> with a status value of 0xF7. The <code>SysexMessage</code>
	* containing the last of the data for the system exclusive message should end with the
	* value 0xF7 (EOX) to mark the end of the system exclusive message.
	* <p>
	* If system exclusive data from <code>SysexMessages</code> objects is being transmitted
	* using MIDI wire protocol, only the initial 0xF0 status byte, the system exclusive
	* data itself, and the final 0xF7 (EOX) byte should be propagated; any 0xF7 status
	* bytes used to indicate that a <code>SysexMessage</code> contains continuing system
	* exclusive data should not be propagated via MIDI wire protocol.
	*
	* @author David Rivas
	* @author Kara Kytle
	* @author Florian Bomers
	*/
	public class SysexMessage extends MidiMessage {


	// Status byte defines


	/**
	* Status byte for System Exclusive message (0xF0, or 240).
	* @see MidiMessage#getStatus
	*/
	public static final int SYSTEM_EXCLUSIVE = 0xF0; // 240


	/**
	* Status byte for Special System Exclusive message (0xF7, or 247), which is used
	* in MIDI files. It has the same value as END_OF_EXCLUSIVE, which
	* is used in the real-time "MIDI wire" protocol.
	* @see MidiMessage#getStatus
	*/
	public static final int SPECIAL_SYSTEM_EXCLUSIVE = 0xF7; // 247


	// Instance variables


	/*
	* The data bytes for this system exclusive message. These are
	* initialized to <code>null</code> and are set explicitly
	* by {@link #setMessage(int, byte[], int, long) setMessage}.
	*/
	//protected byte[] data = null;


	/**
	* Constructs a new <code>SysexMessage</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 SysexMessage() {
	this(new byte[2]);
	// Default sysex message data: SOX followed by EOX
	data[0] = (byte) (SYSTEM_EXCLUSIVE & 0xFF);
	data[1] = (byte) (ShortMessage.END_OF_EXCLUSIVE & 0xFF);
	}

	/**
	* Constructs a new {@code SysexMessage} and sets the data for
	* the message. The first byte of the data array must be a valid system
	* exclusive status byte (0xF0 or 0xF7).
	* The contents of the message can be changed by using one of
	* the {@code setMessage} methods.
	*
	* @param data the system exclusive message data including the status byte
	* @param length the length of the valid message data in the array,
	* including the status byte; it should be non-negative and less than
	* or equal to {@code data.length}
	* @throws InvalidMidiDataException if the parameter values
	* do not specify a valid MIDI meta message.
	* @see #setMessage(byte[], int)
	* @see #setMessage(int, byte[], int)
	* @see #getData()
	* @since 1.7
	*/
	public SysexMessage(byte[] data, int length)
	throws InvalidMidiDataException {
	super(null);
	setMessage(data, length);
	}

	/**
	* Constructs a new {@code SysexMessage} and sets the data for the message.
	* The contents of the message can be changed by using one of
	* the {@code setMessage} methods.
	*
	* @param status the status byte for the message; it must be a valid system
	* exclusive status byte (0xF0 or 0xF7)
	* @param data the system exclusive message data (without the status byte)
	* @param length the length of the valid message data in the array;
	* it should be non-negative and less than or equal to
	* {@code data.length}
	* @throws InvalidMidiDataException if the parameter values
	* do not specify a valid MIDI meta message.
	* @see #setMessage(byte[], int)
	* @see #setMessage(int, byte[], int)
	* @see #getData()
	* @since 1.7
	*/
	public SysexMessage(int status, byte[] data, int length)
	throws InvalidMidiDataException {
	super(null);
	setMessage(status, data, length);
	}


	/**
	* Constructs a new <code>SysexMessage</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
	*/
	protected SysexMessage(byte[] data) {
	super(data);
	}


	/**
	* Sets the data for the system exclusive message. The
	* first byte of the data array must be a valid system
	* exclusive status byte (0xF0 or 0xF7).
	* @param data the system exclusive message data
	* @param length the length of the valid message data in
	* the array, including the status byte.
	*/
	public void setMessage(byte[] data, int length) throws InvalidMidiDataException {
	int status = (data[0] & 0xFF);
	if ((status != 0xF0) && (status != 0xF7)) {
	throw new InvalidMidiDataException("Invalid status byte for sysex message: 0x" + Integer.toHexString(status));
	}
	super.setMessage(data, length);
	}


	/**
	* Sets the data for the system exclusive message.
	* @param status the status byte for the message (0xF0 or 0xF7)
	* @param data the system exclusive message data
	* @param length the length of the valid message data in
	* the array
	* @throws InvalidMidiDataException if the status byte is invalid for a sysex message
	*/
	public void setMessage(int status, byte[] data, int length) throws InvalidMidiDataException {
	if ( (status != 0xF0) && (status != 0xF7) ) {
	throw new InvalidMidiDataException("Invalid status byte for sysex message: 0x" + Integer.toHexString(status));
	}
	if (length < 0 \|\| length > data.length) {
	throw new IndexOutOfBoundsException("length out of bounds: "+length);
	}
	this.length = length + 1;

	if (this.data==null \|\| this.data.length < this.length) {
	this.data = new byte[this.length];
	}

	this.data[0] = (byte) (status & 0xFF);
	if (length > 0) {
	System.arraycopy(data, 0, this.data, 1, length);
	}
	}


	/**
	* Obtains a copy of the data for the system exclusive message.
	* The returned array of bytes does not include the status byte.
	* @return array containing the system exclusive message data.
	*/
	public byte[] getData() {
	byte[] returnedArray = new byte[length - 1];
	System.arraycopy(data, 1, returnedArray, 0, (length - 1));
	return returnedArray;
	}


	/**
	* 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);
	SysexMessage event = new SysexMessage(newData);
	return event;
	}
	}

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