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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

A buffered input stream. This stream lets you read characters from a stream without causing a read every time. The data is read into a buffer, subsequent reads result in a fast buffer access.

Version:
  1.15, 10 May 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.

##

buf

      protected byte buf[]

  The buffer.

count

      protected int count

  The number of bytes in the buffer.

pos

      protected int pos

  The current position in the buffer.

markpos

      protected int markpos

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

marklimit

      protected int marklimit

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

##

BufferedInputStream

      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

##

read

      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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