/*

 * Copyright (c) 1999, 2014, 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

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 */

package com.sun.media.sound;

import javax.sound.midi.MidiDevice;

/**

 * MIDI output device provider.

 *

 * @author Kara Kytle

 * @author Florian Bomers

 */

public final class MidiOutDeviceProvider extends AbstractMidiDeviceProvider {

    /** Cache of info objects for all MIDI output devices on the system. */

    private static Info[] infos = null;

    /** Cache of open MIDI output devices on the system. */

    private static MidiDevice[] devices = null;

    // 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) { MidiOutDeviceProvider.devices = devices; }

    Info[] getInfoCache() { return infos; }

    void setInfoCache(Info[] infos) { MidiOutDeviceProvider.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 final class MidiOutDeviceInfo extends AbstractMidiDeviceProvider.Info {

        private final 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);

}