Listing 2. Drive.java
package Jcd; // 1
/** 3
Jcd - Java CD Audio Player 4
Michael Hamilton (michael@actrix.gen.nz). 5
All rights reserved. See the README for details
*/ // 7
class Drive { // 11
public static final int FRAMES_PER_SECOND = 75;
// Lead out is always track 0xAA // 15
// regardless of the actual number of // 16
// tracks. // 17
public static final int LEAD_OUT = 0xAA; // 18
// Status values returned by the // 20
// status() method. Currently these // 21
// correspond to those values defined // 22
// in <linux/cdrom.h>. Must match // 23
// with those in DriveLib.c // 24
public static final int STATUS_INVALID = 0x00;
public static final int STATUS_PLAY = 0x11;
public static final int STATUS_PAUSED = 0x12;
public static final int STATUS_COMPLETED = 0x13;
public static final int STATUS_ERROR = 0x14;
public static final int STATUS_NOSTATUS = 0x15;
// Device flag values - bit string. // 32
public static final int FLAG_NONE = 0x00;
// Needs stop() before play() // 34
public static final int FLAG_STOP_PLAY = 0x01;
// For now I'll keep the following private.
// Would expand this to include more // 37
// status info if we ever want to support
// multiple CD drives in the same PC. // 39
String device_name = "/dev/cdrom"; // 41
int device_flags = FLAG_NONE; // 42
int fd = -1; // File descriptor. // 44
int audio_status = Drive.STATUS_INVALID; // 46
int number_of_tracks = 0; // 48
int current_track = 0; // 49
int current_index = 0; // 50
int current_address = 0; // number of frames
public Drive() // 53
{ // 54
this("/dev/cdrom", "Jcd_Drive.so", 0); // 55
} // 56
public Drive(String dev,String module,int flags)
{ // 59
System.load(module); // 60
device_name = dev; // 61
device_flags = flags; // 62
try { // 63
// Force an attempt to obtain the device.
initDrive(); // 64
} // 65
catch (DriveException de) { // 66
} // 67
} // 68
native void initDrive() throws DriveException;
// Origin 1. // 72
public native synchronized int currentTrack()
throws DriveException;
// Must call currentTrack() before calling
// currentIndex(). // 76
public native synchronized int currentIndex()
throws DriveException;
public native synchronized int numberOfTracks()
throws DriveException;
// Addresses can vary for the same CD // 81
// produced in different countries. // 82
// Expressed in frame units - 75 // 83
// frames per second. // 84
public native synchronized int currentAddress()
throws DriveException;
public native synchronized int cdEndAddress()
throws DriveException;
public native synchronized int // 87
trackAddress(int n)
throws DriveException;
public native synchronized int // 88
trackLength(int n)
throws DriveException;
public int trackAddress() throws DriveException
{ // 91
return trackAddress(currentTrack()); // 92
} // 93
// 94
public int trackEndAddress(int n)
throws DriveException
{ // 96
return n >= numberOfTracks() ? // 97
cdEndAddress() : trackAddress(n + 1) - 1;
} // 98
public int trackEndAddress()
throws DriveException // 100
{ // 101
return trackEndAddress(currentTrack()); // 102
} // 103
public int trackLength() throws DriveException
{ // 106
return trackLength(currentTrack()); // 107
} // 108
// xjcd cddb address - // 110
// see https://sunsite.unc.edu~/cddb/xjcd/
public native synchronized String cddbID()
throws DriveException; // 112
// CD's product code (might be different
// for the same CD produced in different
// countries? // 116
public native synchronized String productCode()
throws DriveException;
// One of the values defined above. // 119
// Active query of drive. May result // 120
// in drive closing. // 121
public native synchronized int status()
throws DriveException; // 122
// Play from start to end inclusive. // 124
public native synchronized void
play(int startTrack, // 125
int startIndex, // 126
int endTrack, // 127
int endIndex) throws DriveException; // 128
public native synchronized void stop()
throws DriveException; // 130
public native synchronized void pause()
throws DriveException; // 131
public native synchronized void resume()
throws DriveException; // 132
public native synchronized void eject()
throws DriveException; // 133
public native synchronized void
setVolume(int volume) throws DriveException;
public native synchronized int volume()
throws DriveException; // 137
public void play(int n) throws DriveException
{ // Play from n to the end. // 140
play(n, 1, numberOfTracks(), 0); // 141
} // 142
public void play(int n, int i)
throws DriveException // 144
{ // Play from n,i to the end. // 145
play(n, i, numberOfTracks(), 0); // 146
} // 147
public void single(int n) throws DriveException
{ // Play a single track // 150
play(n, 1, n, 0); // 151
} // 152
} // 154
class DriveException extends Exception { // 157
DriveException() { super(); } // 158
DriveException(String s) { super(s); } // 159
} // 160
class TrackAddressException extends DriveException
{ // 162
TrackAddressException() { super(); } // 163
TrackAddressException(String s) { super(s); }
} // 165
class PlayException extends DriveException {
PlayException() { super(); } // 168
PlayException(String s) { super(s); } // 169
} // 170
class StopException extends DriveException {
StopException() { super(); } // 173
StopException(String s) { super(s); } // 174
} // 175
class PauseException extends DriveException {
PauseException() { super(); } // 178
PauseException(String s) { super(s); } // 179
} // 180
class ResumeException extends DriveException {
ResumeException() { super(); } // 183
ResumeException(String s) { super(s); } // 184
} // 185
class EjectException extends DriveException {
EjectException() { super(); } // 188
EjectException(String s) { super(s); } // 189
} // 190
class VolumeException extends DriveException {
VolumeException() { super(); } // 193
VolumeException(String s) { super(s); } // 194
} // 195
class SetVolumeException extends DriveException {
SetVolumeException() { super(); } // 198
SetVolumeException(String s) { super(s);} // 199
} // 200
class ProductCodeException extends DriveException
{ // 202
ProductCodeException() { super(); } // 203
ProductCodeException(String s) { super(s); }
} // 205