1 /*
2 * Copyright (c) 2002, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.media.sound;
27
28 import java.util.Objects;
29
30 import javax.sound.midi.MidiDevice;
31 import javax.sound.midi.spi.MidiDeviceProvider;
32
33 /**
34 * Super class for MIDI input or output device provider.
35 *
36 * @author Florian Bomers
37 */
38 public abstract class AbstractMidiDeviceProvider extends MidiDeviceProvider {
39
40 private static final boolean enabled;
41
42 /**
43 * Create objects representing all MIDI output devices on the system.
44 */
45 static {
46 if (Printer.trace) Printer.trace("AbstractMidiDeviceProvider: static");
47 Platform.initialize();
48 enabled = Platform.isMidiIOEnabled();
49 if (Printer.trace) Printer.trace("AbstractMidiDeviceProvider: enabled: " + enabled);
50
51 // $$fb number of MIDI devices may change with time
52 // also for memory's sake, do not initialize the arrays here
53 }
54
55 final synchronized void readDeviceInfos() {
56 Info[] infos = getInfoCache();
57 MidiDevice[] devices = getDeviceCache();
58 if (!enabled) {
59 if (infos == null || infos.length != 0) {
60 setInfoCache(new Info[0]);
61 }
62 if (devices == null || devices.length != 0) {
63 setDeviceCache(new MidiDevice[0]);
64 }
65 return;
66 }
67
68 int oldNumDevices = (infos==null)?-1:infos.length;
69 int newNumDevices = getNumDevices();
70 if (oldNumDevices != newNumDevices) {
71 if (Printer.trace) Printer.trace(getClass().toString()
72 +": readDeviceInfos: old numDevices: "+oldNumDevices
73 +" newNumDevices: "+ newNumDevices);
74
75 // initialize the arrays
76 Info[] newInfos = new Info[newNumDevices];
77 MidiDevice[] newDevices = new MidiDevice[newNumDevices];
78
79 for (int i = 0; i < newNumDevices; i++) {
80 Info newInfo = createInfo(i);
81
82 // in case that we are re-reading devices, try to find
83 // the previous one and reuse it
84 if (infos != null) {
85 for (int ii = 0; ii < infos.length; ii++) {
86 Info info = infos[ii];
87 if (info != null && info.equalStrings(newInfo)) {
88 // new info matches the still existing info. Use old one
89 newInfos[i] = info;
90 info.setIndex(i);
91 infos[ii] = null; // prevent re-use
92 newDevices[i] = devices[ii];
93 devices[ii] = null;
94 break;
95 }
96 }
97 }
98 if (newInfos[i] == null) {
99 newInfos[i] = newInfo;
100 }
101 }
102 // the remaining MidiDevice.Info instances in the infos array
103 // have become obsolete.
104 if (infos != null) {
105 for (int i = 0; i < infos.length; i++) {
106 if (infos[i] != null) {
107 // disable this device info
108 infos[i].setIndex(-1);
109 }
110 // what to do with the MidiDevice instances that are left
111 // in the devices array ?? Close them ?
112 }
113 }
114 // commit new list of infos.
115 setInfoCache(newInfos);
116 setDeviceCache(newDevices);
117 }
118 }
119
120 @Override
121 public final MidiDevice.Info[] getDeviceInfo() {
122 readDeviceInfos();
123 Info[] infos = getInfoCache();
124 MidiDevice.Info[] localArray = new MidiDevice.Info[infos.length];
125 System.arraycopy(infos, 0, localArray, 0, infos.length);
126 return localArray;
127 }
128
129 @Override
130 public final MidiDevice getDevice(final MidiDevice.Info info) {
131 Objects.requireNonNull(info);
132 if (info instanceof Info) {
133 readDeviceInfos();
134 MidiDevice[] devices = getDeviceCache();
135 Info[] infos = getInfoCache();
136 Info thisInfo = (Info) info;
137 int index = thisInfo.getIndex();
138 if (index >= 0 && index < devices.length && infos[index] == info) {
139 if (devices[index] == null) {
140 devices[index] = createDevice(thisInfo);
141 }
142 if (devices[index] != null) {
143 return devices[index];
144 }
145 }
146 }
147 throw MidiUtils.unsupportedDevice(info);
148 }
149
150 /**
151 * Info class for MidiDevices. Adds an index value for
152 * making native references to a particular device.
153 */
154 static class Info extends MidiDevice.Info {
155 private int index;
156
157 Info(String name, String vendor, String description, String version, int index) {
158 super(name, vendor, description, version);
159 this.index = index;
160 }
161
162 final boolean equalStrings(Info info) {
163 return (info != null
164 && getName().equals(info.getName())
165 && getVendor().equals(info.getVendor())
166 && getDescription().equals(info.getDescription())
167 && getVersion().equals(info.getVersion()));
168 }
169
170 final int getIndex() {
171 return index;
172 }
173
174 final void setIndex(int index) {
175 this.index = index;
176 }
177
178 } // class Info
179
180 abstract int getNumDevices();
181 abstract MidiDevice[] getDeviceCache();
182 abstract void setDeviceCache(MidiDevice[] devices);
183 abstract Info[] getInfoCache();
184 abstract void setInfoCache(Info[] infos);
185
186 abstract Info createInfo(int index);
187 abstract MidiDevice createDevice(Info info);
188 }