com.graphhopper.util

Class BitUtil

java.lang.Object

com.graphhopper.util.BitUtil

Direct Known Subclasses:

BitUtilBig, BitUtilLittle

public abstract class BitUtil
extends Object

Examples for BIG endianness (default for Java and computer network).

 0=>0100 0001
 1=>1110 1011
 2=>...
 

LITTLE endianness is default for GraphHopper and most microprocessors.

Author:

Peter Karich

Field Summary

Fields

Modifier and Type	Field and Description
static BitUtil	BIG BIG endianness.
static BitUtil	LITTLE Default for GraphHopper

Constructor Summary

Constructors

Constructor and Description
BitUtil()

Method Summary

Modifier and Type	Method and Description
long	combineIntsToLong(int intLow, int intHigh)
abstract byte[]	fromBitString(String str)
long	fromBitString2Long(String str) The only purpose of this method is to test 'reverse'.
void	fromDouble(byte[] bytes, double value)
void	fromDouble(byte[] bytes, double value, int offset)
byte[]	fromDouble(double value)
void	fromFloat(byte[] bytes, float value)
void	fromFloat(byte[] bytes, float value, int offset)
byte[]	fromFloat(float value)
void	fromInt(byte[] bytes, int value)
abstract void	fromInt(byte[] bytes, int value, int offset)
byte[]	fromInt(int value)
void	fromLong(byte[] bytes, long value)
abstract void	fromLong(byte[] bytes, long value, int offset)
byte[]	fromLong(long value)
void	fromShort(byte[] bytes, short value)
abstract void	fromShort(byte[] bytes, short value, int offset)
byte[]	fromShort(short value)
static BitUtil	get(ByteOrder order)
int	getIntHigh(long longValue)
int	getIntLow(long longValue)
long	reverse(long value, int maxBits) Reverses the bits in the specified long value and it removes the remaining higher bits.
long	reverseLeft(long value, int maxBits)
abstract String	toBitString(byte[] bytes) Higher order bits comes first in the returned string.
String	toBitString(IntsRef intsRef)
String	toBitString(long value) Similar to Long.toBinaryString
String	toBitString(long value, int bits) Higher order bits comes first in the returned string.
double	toDouble(byte[] bytes)
double	toDouble(byte[] bytes, int offset)
float	toFloat(byte[] bytes)
float	toFloat(byte[] bytes, int offset)
int	toInt(byte[] b)
abstract int	toInt(byte[] b, int offset)
String	toLastBitString(long value, int bits)
long	toLong(byte[] b)
abstract long	toLong(byte[] b, int offset)
abstract long	toLong(int high, int low)
short	toShort(byte[] b)
abstract short	toShort(byte[] b, int offset)

Methods inherited from class java.lang.Object

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

Field Detail

LITTLE

public static final BitUtil LITTLE

Default for GraphHopper

BIG

public static final BitUtil BIG

BIG endianness. Little is the default for GraphHopper.

Constructor Detail

BitUtil

public BitUtil()

Method Detail

get

public static BitUtil get(ByteOrder order)

toDouble

public final double toDouble(byte[] bytes)

toDouble

public final double toDouble(byte[] bytes,
                             int offset)

fromDouble

public final byte[] fromDouble(double value)

fromDouble

public final void fromDouble(byte[] bytes,
                             double value)

fromDouble

public final void fromDouble(byte[] bytes,
                             double value,
                             int offset)

toFloat

public final float toFloat(byte[] bytes)

toFloat

public final float toFloat(byte[] bytes,
                           int offset)

fromFloat

public final byte[] fromFloat(float value)

fromFloat

public final void fromFloat(byte[] bytes,
                            float value)

fromFloat

public final void fromFloat(byte[] bytes,
                            float value,
                            int offset)

toShort

public final short toShort(byte[] b)

toShort

public abstract short toShort(byte[] b,
                              int offset)

toInt

public final int toInt(byte[] b)

toInt

public abstract int toInt(byte[] b,
                          int offset)

fromInt

public final byte[] fromInt(int value)

fromInt

public final void fromInt(byte[] bytes,
                          int value)

fromShort

public final byte[] fromShort(short value)

fromShort

public final void fromShort(byte[] bytes,
                            short value)

fromShort

public abstract void fromShort(byte[] bytes,
                               short value,
                               int offset)

fromInt

public abstract void fromInt(byte[] bytes,
                             int value,
                             int offset)

toLong

public final long toLong(byte[] b)

toLong

public abstract long toLong(int high,
                            int low)

toLong

public abstract long toLong(byte[] b,
                            int offset)

fromLong

public final byte[] fromLong(long value)

fromLong

public final void fromLong(byte[] bytes,
                           long value)

fromLong

public abstract void fromLong(byte[] bytes,
                              long value,
                              int offset)

fromBitString2Long

public final long fromBitString2Long(String str)

The only purpose of this method is to test 'reverse'. toBitString is the reverse and both are independent of the endianness.

fromBitString

public abstract byte[] fromBitString(String str)

toBitString

public final String toBitString(IntsRef intsRef)

toBitString

public final String toBitString(long value)

Similar to Long.toBinaryString

toLastBitString

public String toLastBitString(long value,
                              int bits)

toBitString

public String toBitString(long value,
                          int bits)

Higher order bits comes first in the returned string.

Parameters:

bits - how many bits should be returned.

toBitString

public abstract String toBitString(byte[] bytes)

Higher order bits comes first in the returned string.

reverse

public final long reverse(long value,
                          int maxBits)

Reverses the bits in the specified long value and it removes the remaining higher bits. See also http://graphics.stanford.edu/~seander/bithacks.html#BitReverseObvious

Parameters:

maxBits - the maximum number of recognized bits for reversal

getIntLow

public final int getIntLow(long longValue)

getIntHigh

public final int getIntHigh(long longValue)

combineIntsToLong

public final long combineIntsToLong(int intLow,
                                    int intHigh)

reverseLeft

public final long reverseLeft(long value,
                              int maxBits)