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 javax.sound.midi;
  27 
  28 /**
  29  * A {@code Transmitter} sends {@link MidiEvent} objects to one or more
  30  * {@link Receiver Receivers}. Common MIDI transmitters include sequencers and
  31  * MIDI input ports.
  32  *
  33  * @author Kara Kytle
  34  * @see Receiver
  35  */
  36 public interface Transmitter extends AutoCloseable {
  37 
  38     /**
  39      * Sets the receiver to which this transmitter will deliver MIDI messages.
  40      * If a receiver is currently set, it is replaced with this one.
  41      *
  42      * @param  receiver the desired receiver
  43      */
  44     void setReceiver(Receiver receiver);
  45 
  46     /**
  47      * Obtains the current receiver to which this transmitter will deliver MIDI
  48      * messages.
  49      *
  50      * @return the current receiver. If no receiver is currently set, returns
  51      *         {@code null}.
  52      */
  53     Receiver getReceiver();
  54 
  55     /**
  56      * Indicates that the application has finished using the transmitter, and
  57      * that limited resources it requires may be released or made available.
  58      * <p>
  59      * If the creation of this {@code Transmitter} resulted in implicitly
  60      * opening the underlying device, the device is implicitly closed by this
  61      * method. This is true unless the device is kept open by other
  62      * {@code Receiver} or {@code Transmitter} instances that opened the device
  63      * implicitly, and unless the device has been opened explicitly. If the
  64      * device this {@code Transmitter} is retrieved from is closed explicitly by
  65      * calling {@link MidiDevice#close MidiDevice.close}, the
  66      * {@code Transmitter} is closed, too. For a detailed description of
  67      * open/close behaviour see the class description of
  68      * {@link MidiDevice MidiDevice}.
  69      *
  70      * @see javax.sound.midi.MidiSystem#getTransmitter
  71      */
  72     void close();
  73 }