Source for javax.sound.midi.MidiMessage

   1: /* MidiMessage.java -- base class for MIDI messages.
   2:    Copyright (C) 2005 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package javax.sound.midi;
  40: 
  41: /**
  42:  * The base class for all MIDI messages.
  43:  *
  44:  * @author Anthony Green (green@redhat.com)
  45:  * @since 1.3
  46:  *
  47:  */
  48: public abstract class MidiMessage implements Cloneable
  49: {
  50:   /**
  51:    * MIDI message data.
  52:    */
  53:   protected byte data[];
  54: 
  55:   /**
  56:    * The total length of the MIDI message.
  57:    */
  58:   protected int length;
  59: 
  60:   /**
  61:    * MidiMessage contructor.
  62:    *
  63:    * @param data a valid MIDI message
  64:    */
  65:   protected MidiMessage(byte[] data)
  66:   {
  67:     this.data = data;
  68:     this.length = data.length;
  69:   }
  70: 
  71:   /**
  72:    * Set the complete MIDI message.
  73:    *
  74:    * @param data The complete MIDI message.
  75:    * @param length The length of the MIDI message.
  76:    * @throws InvalidMidiDataException Thrown when the MIDI message is invalid.
  77:    */
  78:   protected void setMessage(byte[] data, int length)
  79:     throws InvalidMidiDataException
  80:   {
  81:     this.data = new byte[length];
  82:     System.arraycopy(data, 0, this.data, 0, length);
  83:     this.length = length;
  84:   }
  85: 
  86:   /**
  87:    * Get the MIDI message data.
  88:    *
  89:    * @return an array containing the MIDI message data
  90:    */
  91:   public byte[] getMessage()
  92:   {
  93:     byte copy[] = new byte[length];
  94:     System.arraycopy(data, 0, copy, 0, length);
  95:     return copy;
  96:   }
  97: 
  98:   /**
  99:    * 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: }