001/* MidiMessage.java -- base class for MIDI messages. 002 Copyright (C) 2005 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package javax.sound.midi; 040 041/** 042 * The base class for all MIDI messages. 043 * 044 * @author Anthony Green (green@redhat.com) 045 * @since 1.3 046 * 047 */ 048public abstract class MidiMessage implements Cloneable 049{ 050 /** 051 * MIDI message data. 052 */ 053 protected byte data[]; 054 055 /** 056 * The total length of the MIDI message. 057 */ 058 protected int length; 059 060 /** 061 * MidiMessage contructor. 062 * 063 * @param data a valid MIDI message 064 */ 065 protected MidiMessage(byte[] data) 066 { 067 this.data = data; 068 this.length = data.length; 069 } 070 071 /** 072 * Set the complete MIDI message. 073 * 074 * @param data The complete MIDI message. 075 * @param length The length of the MIDI message. 076 * @throws InvalidMidiDataException Thrown when the MIDI message is invalid. 077 */ 078 protected void setMessage(byte[] data, int length) 079 throws InvalidMidiDataException 080 { 081 this.data = new byte[length]; 082 System.arraycopy(data, 0, this.data, 0, length); 083 this.length = length; 084 } 085 086 /** 087 * Get the MIDI message data. 088 * 089 * @return an array containing the MIDI message data 090 */ 091 public byte[] getMessage() 092 { 093 byte copy[] = new byte[length]; 094 System.arraycopy(data, 0, copy, 0, length); 095 return copy; 096 } 097 098 /** 099 * Get the status byte of the MIDI message (as an int) 100 * 101 * @return the status byte of the MIDI message (as an int), or zero if the message length is zero. 102 */ 103 public int getStatus() 104 { 105 if (length > 0) 106 return (data[0] & 0xff); 107 else 108 return 0; 109 } 110 111 /** 112 * Get the length of the MIDI message. 113 * 114 * @return the length of the MIDI messsage 115 */ 116 public int getLength() 117 { 118 return length; 119 } 120 121 /* Create a clone of this object. 122 * 123 * @see java.lang.Object#clone() 124 */ 125 public abstract Object clone(); 126}