Package org.yamcs.utils

Class VarIntUtil

java.lang.Object

org.yamcs.utils.VarIntUtil

public class VarIntUtil
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	VarIntUtil.ArrayDecoder	decodes an array of varints
static class	VarIntUtil.SignedArrayDecoder

Constructor Summary

Constructors

Constructor	Description
VarIntUtil()

Method Summary

Modifier and Type	Method	Description
static int[]	decodeDeltaDeltaZigZag(int[] ddz)
static IntArray	decodeDeltaIntArray(byte[] buf)	The reverse of the encodeDeltaIntArray(IntArray) method.
static int	decodeZigZag(int x)
static int[]	encodeDeltaDeltaZigZag(int[] x)
static int[]	encodeDeltaDeltaZigZag(IntArray a)
static int[]	encodeDeltaDeltaZigZag(SortedIntArray a)
static byte[]	encodeDeltaIntArray(IntArray s)	Encode an int array as a sequence of varints representing the deltas between the subsequent elements of the input array.
static int	encodeSigned(byte[] buf, int pos, int x)
static int	encodeZigZag(int x)
static int	getEncodedSize(int value)	get the number of bytes necessary to encode value
static VarIntUtil.ArrayDecoder	newArrayDecoder(byte[] buf)
static int	readSignedVarInt32(ByteBuffer bb)
static String	readSizeDelimitedString(ByteBuffer bb)
static int	readVarInt32(ByteBuffer bb)
static long	readVarInt64(ByteBuffer bb)
static void	writeSignedVarint32(ByteBuffer bb, int x)
static void	writeSizeDelimitedString(ByteBuffer bb, String s)
static int	writeVarInt32(byte[] buf, int pos, int x)	Encodes x as varint in the buffer at position pos and returns the new position
static void	writeVarInt32(ByteBuffer bb, int x)
static void	writeVarInt64(ByteBuffer bb, long x)

Methods inherited from class java.lang.Object

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

Constructor Details

VarIntUtil

public VarIntUtil()

Method Details

writeVarInt32

public static int writeVarInt32(byte[] buf,
 int pos,
 int x)

Encodes x as varint in the buffer at position pos and returns the new position

Parameters:

buf -

x -

Returns:

the decoded integer

writeVarInt32

public static void writeVarInt32(ByteBuffer bb,
 int x)

writeVarInt64

public static void writeVarInt64(ByteBuffer bb,
 long x)

readVarInt32

public static int readVarInt32(ByteBuffer bb)
                        throws DecodingException

Throws:

DecodingException

readVarInt64

public static long readVarInt64(ByteBuffer bb)

writeSignedVarint32

public static void writeSignedVarint32(ByteBuffer bb,
 int x)

readSignedVarInt32

public static int readSignedVarInt32(ByteBuffer bb)
                              throws DecodingException

Throws:

DecodingException

encodeSigned

public static int encodeSigned(byte[] buf,
 int pos,
 int x)

newArrayDecoder

public static VarIntUtil.ArrayDecoder newArrayDecoder(byte[] buf)

decodeZigZag

public static int decodeZigZag(int x)

encodeZigZag

public static int encodeZigZag(int x)

writeSizeDelimitedString

public static void writeSizeDelimitedString(ByteBuffer bb,
 String s)

readSizeDelimitedString

public static String readSizeDelimitedString(ByteBuffer bb)
                                      throws DecodingException

Throws:

DecodingException

encodeDeltaDeltaZigZag

public static int[] encodeDeltaDeltaZigZag(int[] x)

decodeDeltaDeltaZigZag

public static int[] decodeDeltaDeltaZigZag(int[] ddz)

encodeDeltaDeltaZigZag

public static int[] encodeDeltaDeltaZigZag(SortedIntArray a)

encodeDeltaDeltaZigZag

public static int[] encodeDeltaDeltaZigZag(IntArray a)

getEncodedSize

public static int getEncodedSize(int value)

get the number of bytes necessary to encode value

Parameters:

value -

Returns:

encodeDeltaIntArray

public static byte[] encodeDeltaIntArray(IntArray s)

Encode an int array as a sequence of varints representing the deltas between the subsequent elements of the input array. It is best if the array is sorted in ascending order (because encoding negative numbers in varint is not efficient).

Parameters:

s -

Returns:

decodeDeltaIntArray

public static IntArray decodeDeltaIntArray(byte[] buf)

The reverse of the encodeDeltaIntArray(IntArray) method.

Parameters:

buf -

Returns: