Clip interface represents a special kind of data line whose
* audio data can be loaded prior to playback, instead of being streamed in
* real time.
* * Because the data is pre-loaded and has a known length, you can set a clip * to start playing at any position in its audio data. You can also create a * loop, so that when the clip is played it will cycle repeatedly. Loops are * specified with a starting and ending sample frame, along with the number of * times that the loop should be played. *
* Clips may be obtained from a {@link Mixer} that supports lines
* of this type. Data is loaded into a clip when it is opened.
*
* Playback of an audio clip may be started and stopped using the start
* and stop methods. These methods do not reset the media position;
* start causes playback to continue from the position where playback
* was last stopped. To restart playback from the beginning of the clip's audio
* data, simply follow the invocation of {@link DataLine#stop stop}
* with setFramePosition(0), which rewinds the media to the beginning
* of the clip.
*
* @author Kara Kytle
* @since 1.3
*/
public interface Clip extends DataLine {
/**
* A value indicating that looping should continue indefinitely rather than
* complete after a specific number of loops.
* @see #loop
*/
public static final int LOOP_CONTINUOUSLY = -1;
/**
* Opens the clip, meaning that it should acquire any required
* system resources and become operational. The clip is opened
* with the format and audio data indicated.
* If this operation succeeds, the line is marked as open and an
* {@link LineEvent.Type#OPEN OPEN} event is dispatched
* to the line's listeners.
*
* Invoking this method on a line which is already open is illegal * and may result in an IllegalStateException. *
* Note that some lines, once closed, cannot be reopened. Attempts
* to reopen such a line will always result in a
* {@link LineUnavailableException}.
*
* @param format the format of the supplied audio data
* @param data a byte array containing audio data to load into the clip
* @param offset the point at which to start copying, expressed in
* bytes from the beginning of the array
* @param bufferSize the number of bytes
* of data to load into the clip from the array.
* @throws LineUnavailableException if the line cannot be
* opened due to resource restrictions
* @throws IllegalArgumentException if the buffer size does not represent
* an integral number of sample frames,
* or if format is not fully specified or invalid
* @throws IllegalStateException if the line is already open
* @throws SecurityException if the line cannot be
* opened due to security restrictions
*
* @see #close
* @see #isOpen
* @see LineListener
*/
public void open(AudioFormat format, byte[] data, int offset, int bufferSize) throws LineUnavailableException;
/**
* Opens the clip with the format and audio data present in the provided audio
* input stream. Opening a clip means that it should acquire any required
* system resources and become operational. If this operation
* input stream. If this operation
* succeeds, the line is marked open and an
* {@link LineEvent.Type#OPEN OPEN} event is dispatched
* to the line's listeners.
*
* Invoking this method on a line which is already open is illegal * and may result in an IllegalStateException. *
* Note that some lines, once closed, cannot be reopened. Attempts
* to reopen such a line will always result in a
* {@link LineUnavailableException}.
*
* @param stream an audio input stream from which audio data will be read into
* the clip
* @throws LineUnavailableException if the line cannot be
* opened due to resource restrictions
* @throws IOException if an I/O exception occurs during reading of
* the stream
* @throws IllegalArgumentException if the stream's audio format
* is not fully specified or invalid
* @throws IllegalStateException if the line is already open
* @throws SecurityException if the line cannot be
* opened due to security restrictions
*
* @see #close
* @see #isOpen
* @see LineListener
*/
public void open(AudioInputStream stream) throws LineUnavailableException, IOException;
/**
* Obtains the media length in sample frames.
* @return the media length, expressed in sample frames,
* or AudioSystem.NOT_SPECIFIED if the line is not open.
* @see AudioSystem#NOT_SPECIFIED
*/
public int getFrameLength();
/**
* Obtains the media duration in microseconds
* @return the media duration, expressed in microseconds,
* or AudioSystem.NOT_SPECIFIED if the line is not open.
* @see AudioSystem#NOT_SPECIFIED
*/
public long getMicrosecondLength();
/**
* Sets the media position in sample frames. The position is zero-based;
* the first frame is frame number zero. When the clip begins playing the
* next time, it will start by playing the frame at this position.
*
* To obtain the current position in sample frames, use the
* {@link DataLine#getFramePosition getFramePosition}
* method of DataLine.
*
* @param frames the desired new media position, expressed in sample frames
*/
public void setFramePosition(int frames);
/**
* Sets the media position in microseconds. When the clip begins playing the
* next time, it will start at this position.
* The level of precision is not guaranteed. For example, an implementation
* might calculate the microsecond position from the current frame position
* and the audio sample frame rate. The precision in microseconds would
* then be limited to the number of microseconds per sample frame.
*
* To obtain the current position in microseconds, use the
* {@link DataLine#getMicrosecondPosition getMicrosecondPosition}
* method of DataLine.
*
* @param microseconds the desired new media position, expressed in microseconds
*/
public void setMicrosecondPosition(long microseconds);
/**
* Sets the first and last sample frames that will be played in
* the loop. The ending point must be greater than
* or equal to the starting point, and both must fall within the
* the size of the loaded media. A value of 0 for the starting
* point means the beginning of the loaded media. Similarly, a value of -1
* for the ending point indicates the last frame of the media.
* @param start the loop's starting position, in sample frames (zero-based)
* @param end the loop's ending position, in sample frames (zero-based), or
* -1 to indicate the final frame
* @throws IllegalArgumentException if the requested
* loop points cannot be set, usually because one or both falls outside
* the media's duration or because the ending point is
* before the starting point
*/
public void setLoopPoints(int start, int end);
/**
* Starts looping playback from the current position. Playback will
* continue to the loop's end point, then loop back to the loop start point
* count times, and finally continue playback to the end of
* the clip.
*
* If the current position when this method is invoked is greater than the * loop end point, playback simply continues to the * end of the clip without looping. *
* A count value of 0 indicates that any current looping should
* cease and playback should continue to the end of the clip. The behavior
* is undefined when this method is invoked with any other value during a
* loop operation.
*
* If playback is stopped during looping, the current loop status is
* cleared; the behavior of subsequent loop and start requests is not
* affected by an interrupted loop operation.
*
* @param count the number of times playback should loop back from the
* loop's end position to the loop's start position, or
* {@link #LOOP_CONTINUOUSLY} to indicate that looping should
* continue until interrupted
*/
public void loop(int count);
}