/* * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.sun.media.sound; import javax.sound.midi.MidiDevice;import javax.sound.midi.spi.MidiDeviceProvider;  /** * MIDI output device provider. * * @author Kara Kytle * @author Florian Bomers */public class MidiOutDeviceProvider extends AbstractMidiDeviceProvider {     /** Cache of info objects for all MIDI output devices on the system. */    static Info[] infos = null;     /** Cache of open MIDI output devices on the system. */    static MidiDevice[] devices = null;     private static boolean enabled;     // STATIC     static {        // initialize        Platform.initialize();        enabled = Platform.isMidiIOEnabled();    }     // CONSTRUCTOR     /**     * Required public no-arg constructor.     */    public MidiOutDeviceProvider() {        if (Printer.trace) Printer.trace("MidiOutDeviceProvider: constructor");    }     // implementation of abstract methods in AbstractMidiDeviceProvider     AbstractMidiDeviceProvider.Info createInfo(int index) {        if (!enabled) {            return null;        }        return new MidiOutDeviceInfo(index, MidiOutDeviceProvider.class);    }     MidiDevice createDevice(AbstractMidiDeviceProvider.Info info) {        if (enabled && (info instanceof MidiOutDeviceInfo)) {            return new MidiOutDevice(info);        }        return null;    }     int getNumDevices() {        if (!enabled) {            if (Printer.debug)Printer.debug("MidiOutDevice not enabled, returning 0 devices");            return 0;        }        return nGetNumDevices();    }     MidiDevice[] getDeviceCache() { return devices; }    void setDeviceCache(MidiDevice[] devices) { this.devices = devices; }    Info[] getInfoCache() { return infos; }    void setInfoCache(Info[] infos) { this.infos = infos; }      // INNER CLASSES     /**     * Info class for MidiOutDevices.  Adds the     * provider's Class to keep the provider class from being     * unloaded.  Otherwise, at least on JDK1.1.7 and 1.1.8,     * the provider class can be unloaded.  Then, then the provider     * is next invoked, the static block is executed again and a new     * instance of the device object is created.  Even though the     * previous instance may still exist and be open / in use / etc.,     * the new instance will not reflect that state...     */    static class MidiOutDeviceInfo extends AbstractMidiDeviceProvider.Info {        private Class providerClass;         private MidiOutDeviceInfo(int index, Class providerClass) {            super(nGetName(index), nGetVendor(index), nGetDescription(index), nGetVersion(index), index);            this.providerClass = providerClass;        }     } // class MidiOutDeviceInfo      // NATIVE METHODS     private static native int nGetNumDevices();    private static native String nGetName(int index);    private static native String nGetVendor(int index);    private static native String nGetDescription(int index);    private static native String nGetVersion(int index);}