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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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package com.sun.media.sound;
import javax.sound.midi.MidiDevice;
/**
* MIDI input device provider.
*
* @author Kara Kytle
* @author Florian Bomers
*/
public final class MidiInDeviceProvider extends AbstractMidiDeviceProvider {
/** Cache of info objects for all MIDI output devices on the system. */
private static Info[] infos = null;
/** Cache of open MIDI input devices on the system. */
private static MidiDevice[] devices = null;
private static final boolean enabled;
static {
// initialize
Platform.initialize();
enabled = Platform.isMidiIOEnabled();
}
/**
* Required public no-arg constructor.
*/
public MidiInDeviceProvider() {
}
// implementation of abstract methods in AbstractMidiDeviceProvider
@Override
AbstractMidiDeviceProvider.Info createInfo(int index) {
if (!enabled) {
return null;
}
return new MidiInDeviceInfo(index, MidiInDeviceProvider.class);
}
@Override
MidiDevice createDevice(AbstractMidiDeviceProvider.Info info) {
if (enabled && (info instanceof MidiInDeviceInfo)) {
return new MidiInDevice(info);
}
return null;
}
@Override
int getNumDevices() {
if (!enabled) {
return 0;
}
int numDevices = nGetNumDevices();
return numDevices;
}
@Override
MidiDevice[] getDeviceCache() { return devices; }
@Override
void setDeviceCache(MidiDevice[] devices) { MidiInDeviceProvider.devices = devices; }
@Override
Info[] getInfoCache() { return infos; }
@Override
void setInfoCache(Info[] infos) { MidiInDeviceProvider.infos = infos; }
/**
* Info class for MidiInDevices. 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 MidiInDeviceInfo extends AbstractMidiDeviceProvider.Info {
private final Class<?> providerClass;
private MidiInDeviceInfo(int index, Class<?> providerClass) {
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