| /* |
| * Copyright (c) 1999, 2003, 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 javax.sound.sampled; |
| |
| /** |
| * The <code>LineEvent</code> class encapsulates information that a line |
| * sends its listeners whenever the line opens, closes, starts, or stops. |
| * Each of these four state changes is represented by a corresponding |
| * type of event. A listener receives the event as a parameter to its |
| * {@link LineListener#update update} method. By querying the event, |
| * the listener can learn the type of event, the line responsible for |
| * the event, and how much data the line had processed when the event occurred. |
| * |
| * <p>Although this class implements Serializable, attempts to |
| * serialize a <code>LineEvent</code> object will fail. |
| * |
| * @author Kara Kytle |
| * |
| * @see Line |
| * @see LineListener#update |
| * @since 1.3 |
| * |
| * @serial exclude |
| */ |
| public class LineEvent extends java.util.EventObject { |
| |
| // INSTANCE VARIABLES |
| |
| /** |
| * The kind of line event (<code>OPEN</code>, <code>CLOSE</code>, |
| * <code>START</code>, or <code>STOP</code>). |
| * @see #getType |
| * @serial |
| */ |
| private final Type type; |
| |
| /** |
| * The media position when the event occurred, expressed in sample frames. |
| * Note that this field is only relevant to certain events generated by |
| * data lines, such as <code>START</code> and <code>STOP</code>. For |
| * events generated by lines that do not count sample frames, and for any |
| * other events for which this value is not known, the position value |
| * should be {@link AudioSystem#NOT_SPECIFIED}. |
| * @serial |
| * @see #getFramePosition |
| */ |
| private final long position; |
| |
| |
| /** |
| * Constructs a new event of the specified type, originating from the specified line. |
| * @param line the source of this event |
| * @param type the event type (<code>OPEN</code>, <code>CLOSE</code>, <code>START</code>, or <code>STOP</code>) |
| * @param position the number of sample frames that the line had already processed when the event occurred, |
| * or {@link AudioSystem#NOT_SPECIFIED} |
| * |
| * @throws IllegalArgumentException if <code>line</code> is |
| * <code>null</code>. |
| */ |
| public LineEvent(Line line, Type type, long position) { |
| |
| super(line); |
| this.type = type; |
| this.position = position; |
| } |
| |
| /** |
| * Obtains the audio line that is the source of this event. |
| * @return the line responsible for this event |
| */ |
| public final Line getLine() { |
| |
| return (Line)getSource(); |
| } |
| |
| |
| /** |
| * Obtains the event's type. |
| * @return this event's type ({@link Type#OPEN}, {@link Type#CLOSE}, |
| * {@link Type#START}, or {@link Type#STOP}) |
| */ |
| public final Type getType() { |
| |
| return type; |
| } |
| |
| /** |
| * Obtains the position in the line's audio data when the event occurred, expressed in sample frames. |
| * For example, if a source line had already played back 14 sample frames at the time it was |
| * paused, the pause event would report the line's position as 14. The next frame to be processed |
| * would be frame number 14 using zero-based numbering, or 15 using one-based numbering. |
| * <p> |
| * Note that this field is relevant only to certain events generated by |
| * data lines, such as <code>START</code> and <code>STOP</code>. For |
| * events generated by lines that do not count sample frames, and for any |
| * other events for which this value is not known, the position value |
| * should be {@link AudioSystem#NOT_SPECIFIED}. |
| * |
| * @return the line's position as a sample frame number |
| */ |
| /* |
| * $$kk: 04.20.99: note to myself: should make sure our implementation is consistent with this. |
| * which is a reasonable definition.... |
| */ |
| public final long getFramePosition() { |
| |
| return position; |
| } |
| |
| /** |
| * Obtains a string representation of the event. The contents of the string may vary |
| * between implementations of Java Sound. |
| * @return a string describing the event. |
| */ |
| public String toString() { |
| String sType = ""; |
| if (type != null) sType = type.toString()+" "; |
| String sLine; |
| if (getLine() == null) { |
| sLine = "null"; |
| } else { |
| sLine = getLine().toString(); |
| } |
| return new String(sType + "event from line " + sLine); |
| } |
| |
| |
| /** |
| * The LineEvent.Type inner class identifies what kind of event occurred on a line. |
| * Static instances are provided for the common types (OPEN, CLOSE, START, and STOP). |
| * |
| * @see LineEvent#getType() |
| */ |
| public static class Type { |
| |
| |
| /** |
| * Type name. |
| */ |
| // $$kk: 03.25.99: why can't this be final?? |
| private /*final*/ String name; |
| |
| /** |
| * Constructs a new event type. |
| * @param name name of the type |
| */ |
| protected Type(String name) { |
| this.name = name; |
| } |
| |
| |
| //$$fb 2002-11-26: fix for 4695001: SPEC: description of equals() method contains typo |
| /** |
| * Indicates whether the specified object is equal to this event type, |
| * returning <code>true</code> if the objects are identical. |
| * @param obj the reference object with which to compare |
| * @return <code>true</code> if this event type is the same as |
| * <code>obj</code>; <code>false</code> otherwise |
| */ |
| public final boolean equals(Object obj) { |
| return super.equals(obj); |
| } |
| |
| |
| /** |
| * Finalizes the hashcode method. |
| */ |
| public final int hashCode() { |
| return super.hashCode(); |
| } |
| |
| |
| /** |
| * Returns the type name as the string representation. |
| */ |
| public String toString() { |
| return name; |
| } |
| |
| |
| // LINE EVENT TYPE DEFINES |
| |
| /** |
| * A type of event that is sent when a line opens, reserving system |
| * resources for itself. |
| * @see #CLOSE |
| * @see Line#open |
| */ |
| public static final Type OPEN = new Type("Open"); |
| |
| |
| /** |
| * A type of event that is sent when a line closes, freeing the system |
| * resources it had obtained when it was opened. |
| * @see #OPEN |
| * @see Line#close |
| */ |
| public static final Type CLOSE = new Type("Close"); |
| |
| |
| /** |
| * A type of event that is sent when a line begins to engage in active |
| * input or output of audio data in response to a |
| * {@link DataLine#start start} request. |
| * @see #STOP |
| * @see DataLine#start |
| */ |
| public static final Type START = new Type("Start"); |
| |
| |
| /** |
| * A type of event that is sent when a line ceases active input or output |
| * of audio data in response to a {@link DataLine#stop stop} request, |
| * or because the end of media has been reached. |
| * @see #START |
| * @see DataLine#stop |
| */ |
| public static final Type STOP = new Type("Stop"); |
| |
| |
| /** |
| * A type of event that is sent when a line ceases to engage in active |
| * input or output of audio data because the end of media has been reached. |
| */ |
| /* |
| * ISSUE: we may want to get rid of this. Is JavaSound |
| * responsible for reporting this?? |
| * |
| * [If it's decided to keep this API, the docs will need to be updated to include mention |
| * of EOM events elsewhere.] |
| */ |
| //public static final Type EOM = new Type("EOM"); |
| |
| |
| /** |
| * A type of event that is sent when a line begins to engage in active |
| * input or output of audio data. Examples of when this happens are |
| * when a source line begins or resumes writing data to its mixer, and |
| * when a target line begins or resumes reading data from its mixer. |
| * @see #STOP |
| * @see SourceDataLine#write |
| * @see TargetDataLine#read |
| * @see DataLine#start |
| */ |
| //public static final Type ACTIVE = new Type("ACTIVE"); |
| |
| |
| /** |
| * A type of event that is sent when a line ceases active input or output |
| * of audio data. |
| * @see #START |
| * @see DataLine#stop |
| */ |
| //public static final Type INACTIVE = new Type("INACTIVE"); |
| |
| } // class Type |
| |
| } // class LineEvent |