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Class java.io.BufferedInputStream

java.lang.Object
   |
   +----java.io.InputStream
           |
           +----java.io.FilterInputStream
                   |
                   +----java.io.BufferedInputStream

public class BufferedInputStream

extends FilterInputStream

Version:

1.14, 31 Jan 1995

Author:

Arthur van Hoff

buf

The buffer.

count

The number of bytes in the buffer.

marklimit

The maximum readahead allowed after a mark() before subsequent calls to reset() fail.

markpos

The position in the buffer of the current mark.

pos

The current position in the buffer.

BufferedInputStream(InputStream)

Creates a new buffered stream with a default buffer size.

BufferedInputStream(InputStream, int)

Creates a new buffered stream with a given buffer size.

available()

Returns the number of bytes that can be read without blocking.

mark(int)

Mark the current position in the input stream.

markSupported()

Return true since this stream type supports mark/reset

read()

Reads a byte.

read(byte[], int, int)

Reads into an array of bytes.

reset()

Reposition the stream to the last marked position.

skip(int)

Skips bytes of input.

  protected byte buf[]

The buffer.

  protected int count

The number of bytes in the buffer.

  protected int pos

The current position in the buffer.

  protected int markpos

The position in the buffer of the current mark. -1 if there is no current mark.

  protected int marklimit

The maximum readahead allowed after a mark() before subsequent calls to reset() fail.

  public BufferedInputStream(InputStream in)

Creates a new buffered stream with a default buffer size.

Parameters:

in - the input stream

BufferedInputStream

  public BufferedInputStream(InputStream in,
                             int size)

Creates a new buffered stream with a given buffer size.

Parameters:

in - the input stream

size - the buffer size

  public synchronized int read()

Reads a byte. Will block if no input is available.

Returns:

the byte read, or -1 if the end of the stream is reached.

Throws: IOException

i/o error occurred

Overrides:

read in class FilterInputStream

read

  public synchronized int read(byte b[],
                               int off,
                               int len)

Reads into an array of bytes. Blocks until some input is available. This method should be overridden in a subclass for efficiency (the default implementation reads 1 byte at a time).

Parameters:

b - the buffer into which the data is read

off - the start offset of the data

len - the maximum number of bytes read

Returns:

the actual number of bytes read, -1 is returned when the end of the stream is reached.

Throws: IOException

i/o error occurred

Overrides:

read in class FilterInputStream

skip

  public synchronized int skip(int n)

Skips bytes of input.

Parameters:

n - bytes to be skipped

Returns:

actual number of bytes skipped

Throws: IOException

i/o error occurred

Overrides:

skip in class FilterInputStream

available

  public synchronized int available()

Returns the number of bytes that can be read without blocking. This is the total of the number of bytes in the buffer and the number of bytes available from the input stream.

Returns:

the number of available bytes

Overrides:

available in class FilterInputStream

mark

  public synchronized void mark(int readlimit)

Mark the current position in the input stream. A subsequent call to reset() will reposition the stream at the last marked position so that subsequent reads will re-read the same bytes. The stream promises to allow readlimit bytes to be read before the mark position gets invalidated.

Overrides:

mark in class FilterInputStream

reset

  public synchronized void reset()

Reposition the stream to the last marked position. If the stream has not been marked, or if the mark has been invalidated, an IOException is thrown. Stream marks are intended to be used in situations where you need to read ahead a little to see what's in the stream. Often this is most easily done by invoking some general parser. If the stream is of the type handled by the parse, it just chugs along happily. If the stream is *not* of that type, the parser should toss an exception when it fails, which, if it happens within readlimit bytes, allows the outer code to reset the stream and try another parser.

Overrides:

reset in class FilterInputStream

markSupported

  public boolean markSupported()

Return true since this stream type supports mark/reset

Overrides:

markSupported in class FilterInputStream

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