Package com.pnfsoftware.jeb.util.io

Class ByteBufferUtil

java.lang.Object

com.pnfsoftware.jeb.util.io.ByteBufferUtil

public class ByteBufferUtil
extends Object

Utility methods for ByteBuffers.

Constructor Summary

Constructors

Constructor	Description
ByteBufferUtil()

Method Summary

Modifier and Type	Method	Description
static int	align(ByteBuffer b, int align)	Align the buffer using the provided byte alignment.
static boolean	equalsByteArray(ByteBuffer b, int bufferOffset, byte[] a, int arrayOffset, int size)	Compare bytes of a buffer against the bytes of an array.
static byte[]	getBytes(ByteBuffer b)	Read the remaining bytes of a buffer.
static byte[]	getBytes(ByteBuffer b, int offset, int size)	Extract a sequence of bytes from a buffer into a newly-created byte array.
static long	getUnsignedInt(ByteBuffer b)	Unpack a 4-byte int and zero-extend it to a long.
static long	getUnsignedInt(ByteBuffer b, int index)	Unpack a 4-byte int and zero-extend it to a long.
static void	skip(ByteBuffer b, int n)	Skip bytes, including "backward skipping".
static int	skipAttempt(ByteBuffer b, int n)	Attempt to skip bytes, including "backward skipping".
static void	skipToEnd(ByteBuffer b)	Go to the end of the buffer.
static ByteBuffer	wrapBE(byte[] array)	Wrap the provided bytes in a big-endian buffer.
static ByteBuffer	wrapBE(byte[] array, int offset, int length)	Wrap the provided bytes in a big-endian buffer.
static ByteBuffer	wrapLE(byte[] array)	Wrap the provided bytes in a little-endian buffer.
static ByteBuffer	wrapLE(byte[] array, int offset, int length)	Wrap the provided bytes in a little-endian buffer.

Methods inherited from class java.lang.Object

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

Constructor Details

ByteBufferUtil

public ByteBufferUtil()

Method Details

equalsByteArray

public static boolean equalsByteArray(ByteBuffer b,
 int bufferOffset,
 byte[] a,
 int arrayOffset,
 int size)

Compare bytes of a buffer against the bytes of an array.

Parameters:

b - source buffer

bufferOffset - offset in buffer

a - source array

arrayOffset - offset in array

size - number to bytes to be compared

Returns:

true on equality

getBytes

public static byte[] getBytes(ByteBuffer b,
 int offset,
 int size)

Extract a sequence of bytes from a buffer into a newly-created byte array.

Parameters:

b -

offset - offset in `b` (!)

size - number of bytes to read, from `b.position()`

Returns:

getBytes

public static byte[] getBytes(ByteBuffer b)

Read the remaining bytes of a buffer.

Parameters:

b -

Returns:

skip

public static void skip(ByteBuffer b,
 int n)

Skip bytes, including "backward skipping". An exception is raised if the exact amount of bytes could not be skipped.

Parameters:

b - buffer

n - number of bytes to skip (move forward); can be negative to partially rewind the pointer

skipAttempt

public static int skipAttempt(ByteBuffer b,
 int n)

Attempt to skip bytes, including "backward skipping".

Parameters:

b - buffer

n - number of bytes to skip

Returns:

the number of bytes skipped.

skipToEnd

public static void skipToEnd(ByteBuffer b)

Go to the end of the buffer.

Parameters:

b - buffer

getUnsignedInt

public static long getUnsignedInt(ByteBuffer b)

Unpack a 4-byte int and zero-extend it to a long.

Parameters:

b -

Returns:

getUnsignedInt

public static long getUnsignedInt(ByteBuffer b,
 int index)

Unpack a 4-byte int and zero-extend it to a long.

Parameters:

b -

index -

Returns:

wrapLE

public static ByteBuffer wrapLE(byte[] array)

Wrap the provided bytes in a little-endian buffer.

Parameters:

array -

Returns:

wrapBE

public static ByteBuffer wrapBE(byte[] array)

Wrap the provided bytes in a big-endian buffer.

Parameters:

array -

Returns:

wrapLE

public static ByteBuffer wrapLE(byte[] array,
 int offset,
 int length)

Wrap the provided bytes in a little-endian buffer.

Parameters:

array -

offset -

length -

Returns:

wrapBE

public static ByteBuffer wrapBE(byte[] array,
 int offset,
 int length)

Wrap the provided bytes in a big-endian buffer.

Parameters:

array -

offset -

length -

Returns:

align

public static int align(ByteBuffer b,
 int align)

Align the buffer using the provided byte alignment. The position will be increased from anything from 0 to ALIGN-1 bytes so that the new position is congurent to 0 (modulo N).

Parameters:

b -

align - must be >= 1

Returns:

the buffer's new position