Package org.yamcs.utils

Class BitWriter

java.lang.Object

org.yamcs.utils.BitWriter

public class BitWriter
extends Object

Wrapper around a ByteBuffer that allows to write individual bits or group of bits All the writings/readings are performed to a temporary long which is stored into the backing ByteBuffer when it is "full" Don't forget to call flush after the last write, such that the long is written to the backing ByteBuffer

Constructor Summary

Constructors

Constructor	Description
BitWriter(ByteBuffer bb)	Constructs a BitWriter around an existing ByteBuffer

Method Summary

Modifier and Type	Method	Description
void	flush()	flush the temporary long to the ByteBuffer do not call this method twice!!
void	write(int x, int numBits)	write the least significant numBits of x into the BitBuffer Note that there is no check that the bits will actually fit into the ByteBuffer, they will be stored in the temporary field.

Methods inherited from class java.lang.Object

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

Constructor Detail

BitWriter

public BitWriter(ByteBuffer bb)

Constructs a BitWriter around an existing ByteBuffer

Parameters:

bb -

Method Detail

write

public void write(int x,
                  int numBits)

write the least significant numBits of x into the BitBuffer Note that there is no check that the bits will actually fit into the ByteBuffer, they will be stored in the temporary field. A buffer overflow exception will happen when the temporary field is full and flushed to the buffer

Parameters:

x -

numBits -

flush

public void flush()

flush the temporary long to the ByteBuffer do not call this method twice!!