001 /* MidiMessage.java -- base class for MIDI messages. 002 Copyright (C) 2005 Free Software Foundation, Inc. 003 004 This file is part of GNU Classpath. 005 006 GNU Classpath is free software; you can redistribute it and/or modify 007 it under the terms of the GNU General Public License as published by 008 the Free Software Foundation; either version 2, or (at your option) 009 any later version. 010 011 GNU Classpath is distributed in the hope that it will be useful, but 012 WITHOUT ANY WARRANTY; without even the implied warranty of 013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 General Public License for more details. 015 016 You should have received a copy of the GNU General Public License 017 along with GNU Classpath; see the file COPYING. If not, write to the 018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 019 02110-1301 USA. 020 021 Linking this library statically or dynamically with other modules is 022 making a combined work based on this library. Thus, the terms and 023 conditions of the GNU General Public License cover the whole 024 combination. 025 026 As a special exception, the copyright holders of this library give you 027 permission to link this library with independent modules to produce an 028 executable, regardless of the license terms of these independent 029 modules, and to copy and distribute the resulting executable under 030 terms of your choice, provided that you also meet, for each linked 031 independent module, the terms and conditions of the license of that 032 module. An independent module is a module which is not derived from 033 or based on this library. If you modify this library, you may extend 034 this exception to your version of the library, but you are not 035 obligated to do so. If you do not wish to do so, delete this 036 exception statement from your version. */ 037 038 039 package 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 */ 048 public 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 }