org.eclipse.rdf4j.common.io

Class ByteArrayUtil

java.lang.Object

org.eclipse.rdf4j.common.io.ByteArrayUtil

public class ByteArrayUtil
extends Object

Class providing utility methods for handling byte arrays.

Constructor Summary

Constructors

Constructor and Description
ByteArrayUtil()

Method Summary

Modifier and Type	Method and Description
static int	compareRegion(byte[] array1, int startIdx1, byte[] array2, int startIdx2, int length) Compares two regions of bytes, indicating whether one is larger than the other.
static int	find(byte[] a, int fromIndex, int toIndex, byte key) Retrieve a byte from a byte array.
static int	find(byte[] a, int fromIndex, int toIndex, byte[] key) Look for a sequence of bytes in a byte array.
static byte[]	get(byte[] array, int offset) Gets the subarray from array that starts at offset.
static byte[]	get(byte[] array, int offset, int length) Gets the subarray of length length from array that starts at offset.
static int	getInt(byte[] array, int offset) Get an integer value from a byte array at a specific offset.
static long	getLong(byte[] array, int offset) Get a long value from a byte array at a specific offset.
static boolean	matchesPattern(byte[] value, byte[] mask, byte[] pattern) Checks whether value matches pattern with respect to the bits specified by mask.
static void	put(byte[] source, byte[] target, int offset) Puts the entire source array in the target array at offset offset.
static void	putInt(int value, byte[] array, int offset) Put an integer value (padded) in a byte array at a specific offset.
static void	putLong(long value, byte[] array, int offset) Put a long value (padded) in a byte array at a specific offset.
static boolean	regionMatches(byte[] subValue, byte[] superValue, int offset) Checks whether subValue matches the region in superValue starting at offset offset.
static BitSet	toBitSet(byte[] array) Convert a byte array to a vector of bits.
static byte[]	toByteArray(BitSet bitSet) Convert a bitset to a byte array.
static String	toHexString(byte[] array) Returns the hexadecimal value of the supplied byte array.

Methods inherited from class java.lang.Object

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

Constructor Detail

ByteArrayUtil

public ByteArrayUtil()

Method Detail

put

public static void put(byte[] source,
                       byte[] target,
                       int offset)

Puts the entire source array in the target array at offset offset.

Parameters:

source - source array

target - target array

offset - non-negative offset

get

public static byte[] get(byte[] array,
                         int offset)

Gets the subarray from array that starts at offset.

Parameters:

array - source array

offset - non-negative offset

Returns:

byte array

get

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

Gets the subarray of length length from array that starts at offset.

Parameters:

array - byte array

offset - non-negative offset

length - length

Returns:

byte array

putInt

public static void putInt(int value,
                          byte[] array,
                          int offset)

Put an integer value (padded) in a byte array at a specific offset.

Parameters:

value - integer value

array - byte array

offset - non-negative offset

getInt

public static int getInt(byte[] array,
                         int offset)

Get an integer value from a byte array at a specific offset.

Parameters:

array - byte array

offset - non-negative offset

Returns:

integer value

putLong

public static void putLong(long value,
                           byte[] array,
                           int offset)

Put a long value (padded) in a byte array at a specific offset.

Parameters:

value - long value

array - byte array

offset - non-negative offset

getLong

public static long getLong(byte[] array,
                           int offset)

Get a long value from a byte array at a specific offset.

Parameters:

array - byte array

offset - offset

Returns:

long value

find

public static int find(byte[] a,
                       int fromIndex,
                       int toIndex,
                       byte key)

Retrieve a byte from a byte array.

Parameters:

a - the byte array to look in

fromIndex - the position from which to start looking

toIndex - the position up to which to look

key - the byte to find

Returns:

the position of the byte in the array, or -1 if the byte was not found in the array

find

public static int find(byte[] a,
                       int fromIndex,
                       int toIndex,
                       byte[] key)

Look for a sequence of bytes in a byte array.

Parameters:

a - the byte array to look in

fromIndex - the position from which to start looking

toIndex - the position up to which to look

key - the bytes to find

Returns:

the position of the bytes in the array, or -1 if the bytes were not found in the array

matchesPattern

public static boolean matchesPattern(byte[] value,
                                     byte[] mask,
                                     byte[] pattern)

Checks whether value matches pattern with respect to the bits specified by mask. In other words: this method returns true if (value[i] ^ pattern[i]) & mask[i] == 0 for all i.

Parameters:

value - byte array

mask -

pattern - pattern

Returns:

true if pattern was found

regionMatches

public static boolean regionMatches(byte[] subValue,
                                    byte[] superValue,
                                    int offset)

Checks whether subValue matches the region in superValue starting at offset offset.

Parameters:

subValue - value to search for

superValue - byte array

offset - non-negative offset

Returns:

true upon exact match, false otherwise

compareRegion

public static int compareRegion(byte[] array1,
                                int startIdx1,
                                byte[] array2,
                                int startIdx2,
                                int length)

Compares two regions of bytes, indicating whether one is larger than the other.

Parameters:

array1 - The first byte array.

startIdx1 - The start of the region in the first array.

array2 - The second byte array.

startIdx2 - The start of the region in the second array.

length - The length of the region that should be compared.

Returns:

A negative number when the first region is smaller than the second, a positive number when the first region is larger than the second, or 0 if the regions are equal.

toBitSet

public static BitSet toBitSet(byte[] array)

Convert a byte array to a vector of bits.

Parameters:

array - byte array

Returns:

bitset

toByteArray

public static byte[] toByteArray(BitSet bitSet)

Convert a bitset to a byte array.

Parameters:

bitSet - bitset (should not be null)

Returns:

byte array

toHexString

public static String toHexString(byte[] array)

Returns the hexadecimal value of the supplied byte array. The resulting string always uses two hexadecimals per byte. As a result, the length of the resulting string is guaranteed to be twice the length of the supplied byte array.

Parameters:

array - byte array

Returns:

hexadecimal string