javax.sound.sampled
Interface Clip

All Superinterfaces:

DataLine, Line

public interface Clip

extends DataLine

The 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 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 stop with setFramePosition(0), which rewinds the media to the beginning of the clip.

Since:

1.3

Nested Class Summary

 

Nested classes inherited from class javax.sound.sampled.DataLine

DataLine.Info

 

Field Summary
static int	LOOP_CONTINUOUSLY           A value indicating that looping should continue indefinitely rather than complete after a specific number of loops.

 

Method Summary
int	getFrameLength()           Obtains the media length in sample frames.
long	getMicrosecondLength()           Obtains the media duration in microseconds
void	loop(int count)           Starts looping playback from the current position.
void	open(AudioFormat format, byte[] data, int offset, int bufferSize)           Opens the clip, meaning that it should acquire any required system resources and become operational.
void	open(AudioInputStream stream)           Opens the clip with the format and audio data present in the provided audio input stream.
void	setFramePosition(int frames)           Sets the media position in sample frames.
void	setLoopPoints(int start, int end)           Sets the first and last sample frames that will be played in the loop.
void	setMicrosecondPosition(long microseconds)           Sets the media position in microseconds.

 

Methods inherited from interface javax.sound.sampled.DataLine

available, drain, flush, getBufferSize, getFormat, getFramePosition, getLevel, getMicrosecondPosition, isActive, isRunning, start, stop

 

Methods inherited from interface javax.sound.sampled.Line

addLineListener, close, getControl, getControls, getLineInfo, isControlSupported, isOpen, open, removeLineListener

 

Field Detail

LOOP_CONTINUOUSLY

public static final int LOOP_CONTINUOUSLY

A value indicating that looping should continue indefinitely rather than complete after a specific number of loops.

See Also:

loop(int), Constant Field Values

open

public void open(AudioFormat format,
                 byte[] data,
                 int offset,
                 int bufferSize)
          throws LineUnavailableException

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 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 LineUnavailableException.

Parameters:

format - the format of the supplied audio data

data - a byte array containing audio data to load into the clip

offset - the point at which to start copying, expressed in bytes from the beginning of the array

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

IllegalArgumentException - if the buffer size does not represent an integral number of sample frames

IllegalStateException - if the line is already open

SecurityException - if the line cannot be opened due to security restrictions

See Also:

Line.close(), Line.isOpen(), LineListener

open

public void open(AudioInputStream stream)
          throws LineUnavailableException,
                 IOException

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 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 LineUnavailableException.

Parameters:

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

IOException - if an I/O exception occurs during reading of the stream

IllegalStateException - if the line is already open

SecurityException - if the line cannot be opened due to security restrictions

See Also:

Line.close(), Line.isOpen(), LineListener

getFrameLength

public int getFrameLength()

Obtains the media length in sample frames.

Returns:

the media length, expressed in sample frames, or AudioSystem.NOT_SPECIFIED if the line is not open.

See Also:

AudioSystem.NOT_SPECIFIED

getMicrosecondLength

public long getMicrosecondLength()

Obtains the media duration in microseconds

Returns:

the media duration, expressed in microseconds, or AudioSystem.NOT_SPECIFIED if the line is not open.

See Also:

AudioSystem.NOT_SPECIFIED

setFramePosition

public void setFramePosition(int frames)

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 getFramePosition method of DataLine.

Parameters:

frames - the desired new media position, expressed in sample frames

setMicrosecondPosition

public void setMicrosecondPosition(long microseconds)

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 getMicrosecondPosition method of DataLine.

Parameters:

microseconds - the desired new media position, expressed in microseconds

setLoopPoints

public void setLoopPoints(int start,
                          int end)

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.

Parameters:

start - the loop's starting position, in sample frames (zero-based)

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

loop

public void loop(int count)

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.

Parameters:

count - the number of times playback should loop back from the loop's end position to the loop's start position, or LOOP_CONTINUOUSLY to indicate that looping should continue until interrupted