org.ice4j.pseudotcp.util

Class ByteFifoBuffer

java.lang.Object

org.ice4j.pseudotcp.util.ByteFifoBuffer

public class ByteFifoBuffer
extends Object

First in - first out byte buffer

Author:

Pawel Domas

Field Summary

Fields

Modifier and Type	Field and Description
private byte[]	array Backing byte array
private int	buffered Stored bytes count
private int	read_pos Current read position
private int	write_pos Current write position

Constructor Summary

Constructors

Constructor and Description
ByteFifoBuffer(int len) Creates buffer of specified size

Method Summary

Modifier and Type	Method and Description
private void	assertWriteLimit(int newWrPos) Checks if new write position is correct
void	consumeReadData(int count) Aligns current read position by count
void	consumeWriteBuffer(int count) Advances current buffer's write position by count bytes
int	getBuffered()
int	getWriteRemaining()
int	length()
int	read(byte[] out_buffer, int count) Reads count bytes into out_buffer.
int	read(byte[] out_buffer, int buff_offset, int count) Read with buffer offset
private int	readLimit(int desiredReadCount) Limits desiredReadCount to count that is actually available
int	readOffset(byte[] dst_buff, int dst_buff_offset, int count, int offset) Reads count bytes from buffer without storing new read position
private static void	readOp(byte[] outBuffer, int dst_buff_offset, int count, byte[] srcBuffer, int read_pos, int buff_len) Utility method used for read operations
void	resetReadPosition()
void	resetWritePosition()
boolean	setCapacity(int new_size) Sets new buffer's capacity
int	write(byte[] buffer, int count) Writes count of bytes from the buffer
int	write(byte[] data, int offset, int count) Writes data into the buffer.
private int	writeLimit(int desiredWriteCount) Limits desiredWriteCount to what's actually available
int	writeOffset(byte[] data, int count, int nOffset) Writes count bytes from data to the buffer without affecting buffer's write position
private static void	writeOp(byte[] inBuffer, int inOffset, int count, byte[] outBuffer, int write_pos, int buff_len) Utility method for write operations

Methods inherited from class java.lang.Object

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

Field Detail

array

private byte[] array

Backing byte array

write_pos

private int write_pos

Current write position

buffered

private int buffered

Stored bytes count

read_pos

private int read_pos

Current read position

Constructor Detail

ByteFifoBuffer

public ByteFifoBuffer(int len)

Creates buffer of specified size

Parameters:

len - buffer's size

Method Detail

length

public int length()

Returns:

buffer's capacity

read

public int read(byte[] out_buffer,
                int count)

Reads count bytes into out_buffer. Current read position is incremented by count of bytes that has been successfully read.

Parameters:

out_buffer - read count bytes into this buffer

count - number of bytes to read into the out_buffer

Returns:

bytes successfully read

read

public int read(byte[] out_buffer,
                int buff_offset,
                int count)

Read with buffer offset

Parameters:

out_buffer - read count bytes into this buffer

buff_offset - offset where to start writing into out_buffer

count - bytes to read

Returns:

read byte count

readLimit

private int readLimit(int desiredReadCount)

Limits desiredReadCount to count that is actually available

Parameters:

desiredReadCount - desired amount of bytes to read

Returns:

min(buffered, desiredReadCount)

readOp

private static void readOp(byte[] outBuffer,
                           int dst_buff_offset,
                           int count,
                           byte[] srcBuffer,
                           int read_pos,
                           int buff_len)

Utility method used for read operations

Parameters:

outBuffer -

dst_buff_offset -

count -

srcBuffer -

read_pos -

buff_len -

getWriteRemaining

public int getWriteRemaining()

Returns:

space left in buffer for write

getBuffered

public int getBuffered()

Returns:

bytes stored in buffer and available for reading

write

public int write(byte[] buffer,
                 int count)

Writes count of bytes from the buffer

Parameters:

buffer - data to write into the buffer

count - number of bytes to read from the buffer

Returns:

bytes successfully written to buffer

write

public int write(byte[] data,
                 int offset,
                 int count)

Writes data into the buffer.

Parameters:

data - source data

offset - source buffer's offset

count - number of bytes to read from the buffer

Returns:

byte count actually read

writeOp

private static void writeOp(byte[] inBuffer,
                            int inOffset,
                            int count,
                            byte[] outBuffer,
                            int write_pos,
                            int buff_len)

Utility method for write operations

Parameters:

inBuffer -

inOffset -

count -

outBuffer -

write_pos -

buff_len -

writeLimit

private int writeLimit(int desiredWriteCount)

Limits desiredWriteCount to what's actually available

Parameters:

desiredWriteCount -

Returns:

assertWriteLimit

private void assertWriteLimit(int newWrPos)
                       throws IllegalArgumentException

Checks if new write position is correct

Parameters:

newWrPos - new write position

Throws:

IllegalArgumentException

consumeWriteBuffer

public void consumeWriteBuffer(int count)
                        throws IllegalArgumentException,
                               BufferOverflowException

Advances current buffer's write position by count bytes

Parameters:

count - number of bytes to move forward

Throws:

IllegalArgumentException

BufferOverflowException

setCapacity

public boolean setCapacity(int new_size)

Sets new buffer's capacity

Parameters:

new_size - number of bytes

Returns:

true if operation is possible to perform, that is if new buffered data fits into new buffer

consumeReadData

public void consumeReadData(int count)
                     throws IllegalArgumentException,
                            BufferUnderflowException

Aligns current read position by count

Parameters:

count - number of bytes to move the read position

Throws:

BufferUnderflowException - if new position exceeds buffered data count

IllegalArgumentException

readOffset

public int readOffset(byte[] dst_buff,
                      int dst_buff_offset,
                      int count,
                      int offset)

Reads count bytes from buffer without storing new read position

Parameters:

dst_buff - buffer to write the read data to

dst_buff_offset - offset of destination buffer

count - bytes to read

offset - from current read position

Returns:

bytes successfully read

writeOffset

public int writeOffset(byte[] data,
                       int count,
                       int nOffset)
                throws BufferOverflowException

Writes count bytes from data to the buffer without affecting buffer's write position

Parameters:

data - the data to write to the buffer

count - number of bytes to read from data

nOffset - from buffer's write position

Returns:

bytes successfully written

Throws:

BufferOverflowException

resetReadPosition

public void resetReadPosition()

resetWritePosition

public void resetWritePosition()