1 /* 2 * Copyright (c) 1999, 2014, 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 javax.sound.midi.MidiDevice; 29 30 /** 31 * MIDI output device provider. 32 * 33 * @author Kara Kytle 34 * @author Florian Bomers 35 */ 36 public final class MidiOutDeviceProvider extends AbstractMidiDeviceProvider { 37 38 /** Cache of info objects for all MIDI output devices on the system. */ 39 private static Info[] infos = null; 40 41 /** Cache of open MIDI output devices on the system. */ 42 private static MidiDevice[] devices = null; 43 44 private static final boolean enabled; 45 46 static { 47 // initialize 48 Platform.initialize(); 49 enabled = Platform.isMidiIOEnabled(); 50 } 51 52 /** 53 * Required public no-arg constructor. 54 */ 55 public MidiOutDeviceProvider() { 56 if (Printer.trace) Printer.trace("MidiOutDeviceProvider: constructor"); 57 } 58 59 @Override 60 AbstractMidiDeviceProvider.Info createInfo(int index) { 61 if (!enabled) { 62 return null; 63 } 64 return new MidiOutDeviceInfo(index, MidiOutDeviceProvider.class); 65 } 66 67 @Override 68 MidiDevice createDevice(AbstractMidiDeviceProvider.Info info) { 69 if (enabled && (info instanceof MidiOutDeviceInfo)) { 70 return new MidiOutDevice(info); 71 } 72 return null; 73 } 74 75 @Override 76 int getNumDevices() { 77 if (!enabled) { 78 if (Printer.debug)Printer.debug("MidiOutDevice not enabled, returning 0 devices"); 79 return 0; 80 } 81 return nGetNumDevices(); 82 } 83 84 @Override 85 MidiDevice[] getDeviceCache() { return devices; } 86 @Override 87 void setDeviceCache(MidiDevice[] devices) { MidiOutDeviceProvider.devices = devices; } 88 @Override 89 Info[] getInfoCache() { return infos; } 90 @Override 91 void setInfoCache(Info[] infos) { MidiOutDeviceProvider.infos = infos; } 92 93 /** 94 * Info class for MidiOutDevices. Adds the 95 * provider's Class to keep the provider class from being 96 * unloaded. Otherwise, at least on JDK1.1.7 and 1.1.8, 97 * the provider class can be unloaded. Then, then the provider 98 * is next invoked, the static block is executed again and a new 99 * instance of the device object is created. Even though the 100 * previous instance may still exist and be open / in use / etc., 101 * the new instance will not reflect that state... 102 */ 103 static final class MidiOutDeviceInfo extends AbstractMidiDeviceProvider.Info { 104 private final Class<?> providerClass; 105 106 private MidiOutDeviceInfo(int index, Class<?> providerClass) { 107 super(nGetName(index), nGetVendor(index), nGetDescription(index), nGetVersion(index), index); 108 this.providerClass = providerClass; 109 } 110 111 } // class MidiOutDeviceInfo 112 113 private static native int nGetNumDevices(); 114 private static native String nGetName(int index); 115 private static native String nGetVendor(int index); 116 private static native String nGetDescription(int index); 117 private static native String nGetVersion(int index); 118 }