JavaTM 2 Platform
Standard Ed. 5.0

javax.sound.sampled
Class AudioInputStream

java.lang.Object
  extended by java.io.InputStream
      extended by javax.sound.sampled.AudioInputStream
All Implemented Interfaces:
Closeable

public class AudioInputStream
extends InputStream

An audio input stream is an input stream with a specified audio format and length. The length is expressed in sample frames, not bytes. Several methods are provided for reading a certain number of bytes from the stream, or an unspecified number of bytes. The audio input stream keeps track of the last byte that was read. You can skip over an arbitrary number of bytes to get to a later position for reading. An audio input stream may support marks. When you set a mark, the current position is remembered so that you can return to it later.

The AudioSystem class includes many methods that manipulate AudioInputStream objects. For example, the methods let you:

Since:
1.3
See Also:
AudioSystem, Clip.open(AudioInputStream)

Field Summary
protected  AudioFormat format
          The format of the audio data contained in the stream.
protected  long frameLength
          This stream's length, in sample frames.
protected  long framePos
          The current position in this stream, in sample frames (zero-based).
protected  int frameSize
          The size of each frame, in bytes.
 
Constructor Summary
AudioInputStream(InputStream stream, AudioFormat format, long length)
          Constructs an audio input stream that has the requested format and length in sample frames, using audio data from the specified input stream.
AudioInputStream(TargetDataLine line)
          Constructs an audio input stream that reads its data from the target data line indicated.
 
Method Summary
 int available()
          Returns the maximum number of bytes that can be read (or skipped over) from this audio input stream without blocking.
 void close()
          Closes this audio input stream and releases any system resources associated with the stream.
 AudioFormat getFormat()
          Obtains the audio format of the sound data in this audio input stream.
 long getFrameLength()
          Obtains the length of the stream, expressed in sample frames rather than bytes.
 void mark(int readlimit)
          Marks the current position in this audio input stream.
 boolean markSupported()
          Tests whether this audio input stream supports the mark and reset methods.
 int read()
          Reads the next byte of data from the audio input stream.
 int read(byte[] b)
          Reads some number of bytes from the audio input stream and stores them into the buffer array b.
 int read(byte[] b, int off, int len)
          Reads up to a specified maximum number of bytes of data from the audio stream, putting them into the given byte array.
 void reset()
          Repositions this audio input stream to the position it had at the time its mark method was last invoked.
 long skip(long n)
          Skips over and discards a specified number of bytes from this audio input stream.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

format

protected AudioFormat format
The format of the audio data contained in the stream.


frameLength

protected long frameLength
This stream's length, in sample frames.


frameSize

protected int frameSize
The size of each frame, in bytes.


framePos

protected long framePos
The current position in this stream, in sample frames (zero-based).

Constructor Detail

AudioInputStream

public AudioInputStream(InputStream stream,
                        AudioFormat format,
                        long length)
Constructs an audio input stream that has the requested format and length in sample frames, using audio data from the specified input stream.

Parameters:
stream - the stream on which this AudioInputStream object is based
format - the format of this stream's audio data
length - the length in sample frames of the data in this stream

AudioInputStream

public AudioInputStream(TargetDataLine line)
Constructs an audio input stream that reads its data from the target data line indicated. The format of the stream is the same as that of the target data line, and the length is AudioSystem#NOT_SPECIFIED.

Parameters:
line - the target data line from which this stream obtains its data.
See Also:
AudioSystem.NOT_SPECIFIED
Method Detail

getFormat

public AudioFormat getFormat()
Obtains the audio format of the sound data in this audio input stream.

Returns:
an audio format object describing this stream's format

getFrameLength

public long getFrameLength()
Obtains the length of the stream, expressed in sample frames rather than bytes.

Returns:
the length in sample frames

read

public int read()
         throws IOException
Reads the next byte of data from the audio input stream. The audio input stream's frame size must be one byte, or an IOException will be thrown.

Specified by:
read in class InputStream
Returns:
the next byte of data, or -1 if the end of the stream is reached
Throws:
IOException - if an input or output error occurs
See Also:
read(byte[], int, int), read(byte[]),


read

public int read(byte[] b)
         throws IOException
Reads some number of bytes from the audio input stream and stores them into the buffer array b. The number of bytes actually read is returned as an integer. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

This method will always read an integral number of frames. If the length of the array is not an integral number of frames, a maximum of b.length - (b.length % frameSize) bytes will be read.

Overrides:
read in class InputStream
Parameters:
b - the buffer into which the data is read
Returns:
the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached
Throws:
IOException - if an input or output error occurs
See Also:
read(byte[], int, int), read(), available()

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException
Reads up to a specified maximum number of bytes of data from the audio stream, putting them into the given byte array.

This method will always read an integral number of frames. If len does not specify an integral number of frames, a maximum of len - (len % frameSize) bytes will be read.

Overrides:
read in class InputStream
Parameters:
b - the buffer into which the data is read
off - the offset, from the beginning of array b, at which the data will be written
len - the maximum number of bytes to read
Returns:
the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached
Throws:
IOException - if an input or output error occurs
See Also:
read(byte[]), read(), skip(long), available()

skip

public long skip(long n)
          throws IOException
Skips over and discards a specified number of bytes from this audio input stream.

Overrides:
skip in class InputStream
Parameters:
n - the requested number of bytes to be skipped
Returns:
the actual number of bytes skipped
Throws:
IOException - if an input or output error occurs
See Also:
read(), available()

available

public int available()
              throws IOException
Returns the maximum number of bytes that can be read (or skipped over) from this audio input stream without blocking. This limit applies only to the next invocation of a read or skip method for this audio input stream; the limit can vary each time these methods are invoked. Depending on the underlying stream,an IOException may be thrown if this stream is closed.

Overrides:
available in class InputStream
Returns:
the number of bytes that can be read from this audio input stream without blocking
Throws:
IOException - if an input or output error occurs
See Also:
read(byte[], int, int), read(byte[]), read(), skip(long)

close

public void close()
           throws IOException
Closes this audio input stream and releases any system resources associated with the stream.

Specified by:
close in interface Closeable
Overrides:
close in class InputStream
Throws:
IOException - if an input or output error occurs

mark

public void mark(int readlimit)
Marks the current position in this audio input stream.

Overrides:
mark in class InputStream
Parameters:
readlimit - the maximum number of bytes that can be read before the mark position becomes invalid.
See Also:
reset(), markSupported()

reset

public void reset()
           throws IOException
Repositions this audio input stream to the position it had at the time its mark method was last invoked.

Overrides:
reset in class InputStream
Throws:
IOException - if an input or output error occurs.
See Also:
mark(int), markSupported()

markSupported

public boolean markSupported()
Tests whether this audio input stream supports the mark and reset methods.

Overrides:
markSupported in class InputStream
Returns:
true if this stream supports the mark and reset methods; false otherwise
See Also:
mark(int), reset()

JavaTM 2 Platform
Standard Ed. 5.0

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