public abstract class FilteredAudioInputStream
extends javax.sound.sampled.AudioInputStream
FilteredAudioInputStream
is an AudioInputStream with buffers
to facilitate transcoding the audio.
A first byte array can buffer the data from the underlying inputstream until
sufficient data for transcoding is present.
A second byte array can hold the transcoded audio data, ready to be read out
by the stream user.Modifier and Type | Field and Description |
---|---|
protected byte[] |
buf
The internal buffer array where the data is stored.
|
protected int |
count
The index one greater than the index of the last valid byte in the buffer.
|
static int |
DEFAULT_BUFFER_SIZE
The default size of the buffer.
|
protected java.io.InputStream |
in
The underlying inputStream.
|
protected int |
marklimit
The maximum read ahead allowed after a call to the
mark
method before subsequent calls to the reset method fail. |
protected int |
markpos
The value of the
pos field at the time the last
mark method was called. |
protected int |
pos
The current position in the buffer.
|
protected byte[] |
prebuf
The internal buffer array where the unfiltered data is temporarily stored.
|
protected int |
precount
The index one greater than the index of the last valid byte in the
unfiltered data buffer.
|
protected int |
prepos
The current position in the unfiltered data buffer.
|
private byte[] |
single
Array of size 1, used by the read method to read just 1 byte.
|
Constructor and Description |
---|
FilteredAudioInputStream(java.io.InputStream in,
javax.sound.sampled.AudioFormat format,
long length)
Creates a
FilteredAudioInputStream and saves its argument,
the input stream in , for later use. |
FilteredAudioInputStream(java.io.InputStream in,
javax.sound.sampled.AudioFormat format,
long length,
int size)
Creates a
FilteredAudioInputStream with the specified buffer
size, and saves its argument, the inputstream in for later use. |
FilteredAudioInputStream(java.io.InputStream in,
javax.sound.sampled.AudioFormat format,
long length,
int size,
int presize)
Creates a
FilteredAudioInputStream with the specified buffer
size, and saves its argument, the inputstream in for later use. |
Modifier and Type | Method and Description |
---|---|
int |
available()
Returns the number of bytes that can be read from this inputstream without
blocking.
|
protected void |
checkIfStillOpen()
Check to make sure that this stream has not been closed
|
void |
close()
Closes this input stream and releases any system resources associated with
the stream.
|
protected void |
fill()
Fills the buffer with more data, taking into account shuffling and other
tricks for dealing with marks.
|
protected void |
makeSpace()
Free up some space in the buffers.
|
void |
mark(int readlimit)
See the general contract of the
mark method of
InputStream . |
boolean |
markSupported()
Tests if this input stream supports the
mark and
reset methods. |
int |
read()
See the general contract of the
read method of
InputStream . |
int |
read(byte[] b,
int off,
int len)
Reads bytes from this byte-input stream into the specified byte array,
starting at the given offset.
|
void |
reset()
See the general contract of the
reset method of
InputStream . |
long |
skip(long n)
See the general contract of the
skip method of
InputStream . |
public static final int DEFAULT_BUFFER_SIZE
protected java.io.InputStream in
protected byte[] buf
protected int count
buf.length
;
elements buf[0]
through buf[count-1]
contain
buffered input data obtained and filtered from the underlying inputstream.protected int pos
buf
array.
This value is always in the range 0 through count
.
If it is less than count
, then buf[pos]
is the
next byte to be supplied as input.
If it is equal to count
, then the next read
or
skip
operation will require more bytes to be read and
filtered from the underlying inputstream.
buf
protected int markpos
pos
field at the time the last
mark
method was called.
This value is always in the range -1 through pos
.
If there is no marked position in the inputstream, this field is -1.
If there is a marked position in the inputstream, then
buf[markpos]
is the first byte to be supplied as input after
a reset
operation.
If markpos
is not -1, then all bytes from positions
buf[markpos]
through buf[pos-1]
must remain in
the buffer array (though they may be moved to another place in the buffer
array, with suitable adjustments to the values of count
,
pos
, and markpos
); they may not be discarded
unless and until the difference between pos
and
markpos
exceeds marklimit
.
protected int marklimit
mark
method before subsequent calls to the reset
method fail.
Whenever the difference between pos
and markpos
exceeds marklimit
, then the mark may be dropped by setting
markpos
to -1.private final byte[] single
protected byte[] prebuf
protected int precount
prebuf.length
;
elements prebuf[0]
through prebuf[count-1]
contain buffered input data obtained from the underlying input stream.protected int prepos
prebuf
array.
This value is always in the range 0 through precount
.
If it is less than precount
, then prebuf[pos]
is
the next byte to be supplied as input.
If it is equal to precount
, then the next read
or skip
operation will require more bytes to be read from the
contained inputstream.
prebuf
public FilteredAudioInputStream(java.io.InputStream in, javax.sound.sampled.AudioFormat format, long length)
FilteredAudioInputStream
and saves its argument,
the input stream in
, for later use.
An internal buffer array is created and stored in buf
.in
- the underlying input stream.format
- the format of this stream's audio data.length
- the length in sample frames of the data in this stream.java.lang.IllegalArgumentException
- if size <= 0 or presize <= 0.public FilteredAudioInputStream(java.io.InputStream in, javax.sound.sampled.AudioFormat format, long length, int size)
FilteredAudioInputStream
with the specified buffer
size, and saves its argument, the inputstream in
for later use.
An internal buffer array of length size
is created and stored
in buf
.in
- the underlying input stream.format
- the format of this stream's audio data.length
- the length in sample frames of the data in this stream.size
- the buffer sizes.java.lang.IllegalArgumentException
- if size <= 0.public FilteredAudioInputStream(java.io.InputStream in, javax.sound.sampled.AudioFormat format, long length, int size, int presize)
FilteredAudioInputStream
with the specified buffer
size, and saves its argument, the inputstream in
for later use.
An internal buffer array of length size
is created and stored
in buf
.in
- the underlying input stream.format
- the format of this stream's audio data.length
- the length in sample frames of the data in this stream.size
- the buffer size.presize
- the prebuffer size.java.lang.IllegalArgumentException
- if size <= 0 or presize <= 0.protected void checkIfStillOpen() throws java.io.IOException
java.io.IOException
protected void fill() throws java.io.IOException
java.io.IOException
protected void makeSpace()
public int read() throws java.io.IOException
read
method of
InputStream
.read
in class javax.sound.sampled.AudioInputStream
-1
if the end of the
stream is reached.java.io.IOException
- if an I/O error occurs.in
public int read(byte[] b, int off, int len) throws java.io.IOException
This method implements the general contract of the corresponding
method of
the read
class. As an additional
convenience, it attempts to read as many bytes as possible by repeatedly
invoking the InputStream
read
method of the underlying stream. This
iterated read
continues until one of the following
conditions becomes true:
read
method of the underlying stream returns
-1
, indicating end-of-file, or
available
method of the underlying stream
returns zero, indicating that further input requests would block.
read
on the underlying stream returns
-1
to indicate end-of-file then this method returns
-1
. Otherwise this method returns the number of bytes
actually read.
Subclasses of this class are encouraged, but not required, to attempt to read as many bytes as possible in the same fashion.
read
in class javax.sound.sampled.AudioInputStream
b
- destination buffer.off
- offset at which to start storing bytes.len
- maximum number of bytes to read.-1
if the end of
the stream has been reached.java.io.IOException
- if an I/O error occurs.public long skip(long n) throws java.io.IOException
skip
method of
InputStream
.skip
in class javax.sound.sampled.AudioInputStream
n
- the number of bytes to be skipped.java.io.IOException
- if an I/O error occurs.public int available() throws java.io.IOException
The available
method of FilteredAudioInputStream
returns the sum of the the number of bytes remaining to be read in the
buffer (count - pos
).
The result of calling the available
method of the underlying
inputstream is not used, as this data will have to be filtered, and thus
may not be the same size after processing (although subclasses that do the
filtering should override this method and use the amount of data available
in the underlying inputstream).
available
in class javax.sound.sampled.AudioInputStream
java.io.IOException
- if an I/O error occurs.in
public void mark(int readlimit)
mark
method of
InputStream
.mark
in class javax.sound.sampled.AudioInputStream
readlimit
- the maximum limit of bytes that can be read before
the mark position becomes invalid.reset()
public void reset() throws java.io.IOException
reset
method of
InputStream
.
If markpos
is -1 (no mark has been set or the mark has been
invalidated), an IOException
is thrown.
Otherwise, pos
is set equal to markpos
.
reset
in class javax.sound.sampled.AudioInputStream
java.io.IOException
- if this stream has not been marked or
if the mark has been invalidated.mark(int)
public boolean markSupported()
mark
and
reset
methods. The markSupported
method of
FilteredAudioInputStream
returns true
.public void close() throws java.io.IOException
close
in interface java.io.Closeable
close
in interface java.lang.AutoCloseable
close
in class javax.sound.sampled.AudioInputStream
java.io.IOException
- if an I/O error occurs.Copyright © 1999-2004 Wimba S.A. All Rights Reserved.