net.jini.io
Class OptimizedByteArrayInputStream

java.lang.Object
  java.io.InputStream
      net.jini.io.OptimizedByteArrayInputStream

All Implemented Interfaces:

Closeable

public class OptimizedByteArrayInputStream
extends InputStream

This class is an optimized porting of java.io.ByteArrayInputStream: a) All methods are not synchronized. b) Most safety checks have been removed.

Since:

6.6

Author:

niv

Field Summary

protected byte[]	_buffer An array of bytes that was provided by the creator of the stream.
protected int	_count The index one greater than the last valid character in the input stream buffer.
protected int	_position The index of the next character to read from the input stream buffer.

Constructor Summary

OptimizedByteArrayInputStream(byte[] buffer)
Creates a ByteArrayInputStream so that it uses buffer as its buffer array.

Method Summary

int	available() Returns the number of bytes that can be read from this input stream without blocking.
int	read() Reads the next byte of data from this input stream.
int	read(byte[] b, int off, int len) Reads up to len bytes of data into an array of bytes from this input stream.
byte	readByte()
int	readUnsignedByte()
void	setBuffer(byte[] buffer) Sets a GSByteArrayInputStream so that it uses buffer as its buffer array.
long	skip(long n) Skips n bytes of input from this input stream.

Methods inherited from class java.io.InputStream

close, mark, markSupported, read, reset

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_buffer

protected byte[] _buffer

An array of bytes that was provided by the creator of the stream. Elements buf[0] through buffer[count-1] are the only bytes that can ever be read from the stream; element buffer[pos] is the next byte to be read.

_position

protected int _position

The index of the next character to read from the input stream buffer. This value should always be nonnegative and not larger than the value of count. The next byte to be read from the input stream buffer will be buffer[position].

_count

protected int _count

The index one greater than the last valid character in the input stream buffer. This value should always be nonnegative and not larger than the length of buffer. It is one greater than the position of the last byte within buffer that can ever be read from the input stream buffer.

Constructor Detail

OptimizedByteArrayInputStream

public OptimizedByteArrayInputStream(byte[] buffer)

Creates a ByteArrayInputStream so that it uses buffer as its buffer array. The buffer array is not copied. The initial value of pos is 0 and the initial value of count is the length of buffer.

Parameters:

buffer - the input buffer.

Method Detail

setBuffer

public void setBuffer(byte[] buffer)

Sets a GSByteArrayInputStream so that it uses buffer as its buffer array. The buffer array is not copied. The initial value of pos is 0 and the initial value of count is the length of buffer.

Parameters:

buffer - the input buffer.

read

public int read()

Reads the next byte of data from this input stream. The value byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned.

This read method cannot block.

Specified by:

read in class InputStream

Returns:

the next byte of data, or -1 if the end of the stream has been reached.

readByte

public byte readByte()

readUnsignedByte

public int readUnsignedByte()

read

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

Reads up to len bytes of data into an array of bytes from this input stream. If pos equals count, then -1 is returned to indicate end of file. Otherwise, the number k of bytes read is equal to the smaller of len and count-pos. If k is positive, then bytes buffer[pos] through buffer[pos+k-1] are copied into b[off] through b[off+k-1] in the manner performed by System.arraycopy. The value k is added into pos and k is returned.

This read method cannot block.

Overrides:

read in class InputStream

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 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.

skip

public long skip(long n)

Skips n bytes of input from this input stream. Fewer bytes might be skipped if the end of the input stream is reached. The actual number k of bytes to be skipped is equal to the smaller of n and count-pos. The value k is added into pos and k is returned.

Overrides:

skip in class InputStream

Parameters:

n - the number of bytes to be skipped.

Returns:

the actual number of bytes skipped.

available

public int available()

Returns the number of bytes that can be read from this input stream without blocking. The value returned is count - pos, which is the number of bytes remaining to be read from the input buffer.

Overrides:

available in class InputStream

Returns:

the number of bytes that can be read from the input stream without blocking.