org.apache.hadoop.hbase.util

Class ByteBufferUtils

java.lang.Object

org.apache.hadoop.hbase.util.ByteBufferUtils

@InterfaceAudience.Public
public final class ByteBufferUtils
extends Object

Utility functions for working with byte buffers, such as reading/writing variable-length long numbers.

Field Summary

Fields

Modifier and Type	Field and Description
static int	NEXT_BIT_MASK
static int	NEXT_BIT_SHIFT
static boolean	UNSAFE_UNALIGNED
static int	VALUE_MASK

Method Summary

Modifier and Type	Method and Description
static boolean	arePartsEqual(ByteBuffer buffer, int offsetLeft, int lengthLeft, int offsetRight, int lengthRight) Check whether two parts in the same buffer are equal.
static int	compareTo(byte[] buf1, int o1, int l1, ByteBuffer buf2, int o2, int l2)
static int	compareTo(ByteBuffer buf1, int o1, int l1, byte[] buf2, int o2, int l2)
static int	compareTo(ByteBuffer buf1, int o1, int l1, ByteBuffer buf2, int o2, int l2)
static void	copyBufferToStream(DataOutput out, ByteBuffer in, int offset, int length) Copy data from a buffer to an output stream.
static void	copyBufferToStream(OutputStream out, ByteBuffer in, int offset, int length) Copy data from a buffer to an output stream.
static void	copyFromArrayToBuffer(ByteBuffer out, byte[] in, int inOffset, int length) Copies the bytes from given array's offset to length part into the given buffer.
static void	copyFromArrayToBuffer(ByteBuffer out, int outOffset, byte[] in, int inOffset, int length) Copies bytes from given array's offset to length part into the given buffer.
static void	copyFromBufferToArray(byte[] out, ByteBuffer in, int sourceOffset, int destinationOffset, int length) Copies specified number of bytes from given offset of 'in' ByteBuffer to the array.
static void	copyFromBufferToBuffer(ByteBuffer in, ByteBuffer out) Copy one buffer's whole data to another.
static void	copyFromBufferToBuffer(ByteBuffer in, ByteBuffer out, int sourceOffset, int length) Copy from one buffer to another from given offset.
static void	copyFromBufferToBuffer(ByteBuffer in, ByteBuffer out, int sourceOffset, int destinationOffset, int length) Copy from one buffer to another from given offset.
static void	copyFromStreamToBuffer(ByteBuffer out, DataInputStream in, int length) Copy the given number of bytes from the given stream and put it at the current position of the given buffer, updating the position in the buffer.
static byte[]	copyOfRange(ByteBuffer original, int from, int to) Similar to Arrays.copyOfRange(byte[], int, int)
static ByteBuffer	drainInputStreamToBuffer(InputStream is) Copy from the InputStream to a new heap ByteBuffer until the InputStream is exhausted.
static boolean	equals(ByteBuffer buf1, int o1, int l1, byte[] buf2, int o2, int l2)
static boolean	equals(ByteBuffer buf1, int o1, int l1, ByteBuffer buf2, int o2, int l2)
static void	extendLimit(ByteBuffer buffer, int numBytes)
static int	findCommonPrefix(byte[] left, int leftOffset, int leftLength, byte[] right, int rightOffset, int rightLength) Find length of common prefix in two arrays.
static int	findCommonPrefix(ByteBuffer left, int leftOffset, int leftLength, ByteBuffer right, int rightOffset, int rightLength) Find length of common prefix in two arrays.
static int	findCommonPrefix(ByteBuffer buffer, int offsetLeft, int offsetRight, int limit) Find length of common prefix of two parts in the buffer
static int	hashCode(ByteBuffer buf, int offset, int length)
static int	intFitsIn(int value) Check how many bytes is required to store value.
static int	longFitsIn(long value) Check how many bytes are required to store value.
static void	moveBufferToStream(OutputStream out, ByteBuffer in, int length) Copy the data to the output stream and update position in buffer.
static int	putAsShort(ByteBuffer buf, int index, int val)
static int	putByte(ByteBuffer buffer, int offset, byte b)
static int	putCompressedInt(OutputStream out, int value) Put in buffer integer using 7 bit encoding.
static void	putInt(ByteBuffer buffer, int val) Put an int value out to the given ByteBuffer's current position in big-endian format.
static int	putInt(ByteBuffer buffer, int index, int val)
static void	putInt(OutputStream out, int value) Put in output stream 32 bit integer (Big Endian byte order).
static int	putLong(ByteBuffer buffer, int index, long val)
static void	putLong(ByteBuffer buffer, long val) Put a long value out to the given ByteBuffer's current position in big-endian format.
static int	putLong(OutputStream out, long value, int fitInBytes)
static int	putShort(ByteBuffer buffer, int index, short val)
static void	putShort(ByteBuffer buffer, short val) Put a short value out to the given ByteBuffer's current position in big-endian format.
static int	readAsInt(ByteBuffer buf, int offset, int length) Converts a ByteBuffer to an int value
static int	readCompressedInt(ByteBuffer buffer) Read integer from buffer coded in 7 bits and increment position.
static int	readCompressedInt(InputStream input) Read integer from stream coded in 7 bits and increment position.
static long	readLong(ByteBuffer in, int fitInBytes) Read long which was written to fitInBytes bytes and increment position.
static long	readLong(InputStream in, int fitInBytes) Read long which was written to fitInBytes bytes and increment position.
static long	readVLong(ByteBuffer in) Similar to WritableUtils.readVLong(DataInput) but reads from a ByteBuffer.
static void	skip(ByteBuffer buffer, int length) Increment position in buffer.
static BigDecimal	toBigDecimal(ByteBuffer buffer, int offset, int length) Reads a BigDecimal value at the given buffer's offset.
static byte	toByte(ByteBuffer buffer, int offset)
static byte[]	toBytes(ByteBuffer buffer, int startPosition) Copy the bytes from position to limit into a new byte[] of the exact length and sets the position and limit back to their original values (though not thread safe).
static byte[]	toBytes(ByteBuffer buffer, int offset, int length) Copy the given number of bytes from specified offset into a new byte[]
static double	toDouble(ByteBuffer buffer, int offset) Reads a double value at the given buffer's offset.
static int	toInt(ByteBuffer buffer) Reads an int value at the given buffer's current position.
static int	toInt(ByteBuffer buffer, int offset) Reads an int value at the given buffer's offset.
static long	toLong(ByteBuffer buffer, int offset) Reads a long value at the given buffer's offset.
static short	toShort(ByteBuffer buffer, int offset) Reads a short value at the given buffer's offset.
static String	toStringBinary(ByteBuffer b)
static String	toStringBinary(ByteBuffer b, int off, int len)
static void	writeVLong(ByteBuffer out, long i) Similar to WritableUtils.writeVLong(java.io.DataOutput, long), but writes to a ByteBuffer.

Methods inherited from class java.lang.Object

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

Field Detail

VALUE_MASK

public static final int VALUE_MASK

See Also:

Constant Field Values

NEXT_BIT_SHIFT

public static final int NEXT_BIT_SHIFT

See Also:

Constant Field Values

NEXT_BIT_MASK

public static final int NEXT_BIT_MASK

See Also:

Constant Field Values

UNSAFE_UNALIGNED

public static final boolean UNSAFE_UNALIGNED

Method Detail

writeVLong

public static void writeVLong(ByteBuffer out,
                              long i)

Similar to WritableUtils.writeVLong(java.io.DataOutput, long), but writes to a ByteBuffer.

readVLong

public static long readVLong(ByteBuffer in)

Similar to WritableUtils.readVLong(DataInput) but reads from a ByteBuffer.

putCompressedInt

public static int putCompressedInt(OutputStream out,
                                   int value)
                            throws IOException

Put in buffer integer using 7 bit encoding. For each written byte: 7 bits are used to store value 1 bit is used to indicate whether there is next bit.

Parameters:

value - Int to be compressed.

out - Where to put compressed data

Returns:

Number of bytes written.

Throws:

IOException - on stream error

putInt

public static void putInt(OutputStream out,
                          int value)
                   throws IOException

Put in output stream 32 bit integer (Big Endian byte order).

Parameters:

out - Where to put integer.

value - Value of integer.

Throws:

IOException - On stream error.

toByte

public static byte toByte(ByteBuffer buffer,
                          int offset)

moveBufferToStream

public static void moveBufferToStream(OutputStream out,
                                      ByteBuffer in,
                                      int length)
                               throws IOException

Copy the data to the output stream and update position in buffer.

Parameters:

out - the stream to write bytes to

in - the buffer to read bytes from

length - the number of bytes to copy

Throws:

IOException

copyBufferToStream

public static void copyBufferToStream(OutputStream out,
                                      ByteBuffer in,
                                      int offset,
                                      int length)
                               throws IOException

Copy data from a buffer to an output stream. Does not update the position in the buffer.

Parameters:

out - the stream to write bytes to

in - the buffer to read bytes from

offset - the offset in the buffer (from the buffer's array offset) to start copying bytes from

length - the number of bytes to copy

Throws:

IOException

copyBufferToStream

public static void copyBufferToStream(DataOutput out,
                                      ByteBuffer in,
                                      int offset,
                                      int length)
                               throws IOException

Copy data from a buffer to an output stream. Does not update the position in the buffer.

Parameters:

out - the output stream to write bytes to

in - the buffer to read bytes from

offset - the offset in the buffer (from the buffer's array offset) to start copying bytes from

length - the number of bytes to copy

Throws:

IOException

putLong

public static int putLong(OutputStream out,
                          long value,
                          int fitInBytes)
                   throws IOException

Throws:

IOException

putByte

public static int putByte(ByteBuffer buffer,
                          int offset,
                          byte b)

longFitsIn

public static int longFitsIn(long value)

Check how many bytes are required to store value.

Parameters:

value - Value which size will be tested.

Returns:

How many bytes are required to store value.

intFitsIn

public static int intFitsIn(int value)

Check how many bytes is required to store value.

Parameters:

value - Value which size will be tested.

Returns:

How many bytes are required to store value.

readCompressedInt

public static int readCompressedInt(InputStream input)
                             throws IOException

Read integer from stream coded in 7 bits and increment position.

Returns:

the integer that has been read

Throws:

IOException

readCompressedInt

public static int readCompressedInt(ByteBuffer buffer)

Read integer from buffer coded in 7 bits and increment position.

Returns:

Read integer.

readLong

public static long readLong(InputStream in,
                            int fitInBytes)
                     throws IOException

Read long which was written to fitInBytes bytes and increment position.

Parameters:

fitInBytes - In how many bytes given long is stored.

Returns:

The value of parsed long.

Throws:

IOException

readLong

public static long readLong(ByteBuffer in,
                            int fitInBytes)

Read long which was written to fitInBytes bytes and increment position.

Parameters:

fitInBytes - In how many bytes given long is stored.

Returns:

The value of parsed long.

copyFromStreamToBuffer

public static void copyFromStreamToBuffer(ByteBuffer out,
                                          DataInputStream in,
                                          int length)
                                   throws IOException

Copy the given number of bytes from the given stream and put it at the current position of the given buffer, updating the position in the buffer.

Parameters:

out - the buffer to write data to

in - the stream to read data from

length - the number of bytes to read/write

Throws:

IOException

drainInputStreamToBuffer

public static ByteBuffer drainInputStreamToBuffer(InputStream is)
                                           throws IOException

Copy from the InputStream to a new heap ByteBuffer until the InputStream is exhausted.

Throws:

IOException

copyFromBufferToBuffer

public static void copyFromBufferToBuffer(ByteBuffer in,
                                          ByteBuffer out)

Copy one buffer's whole data to another. Write starts at the current position of 'out' buffer. Note : This will advance the position marker of out and also change the position maker for in.

Parameters:

in - source buffer

out - destination buffer

copyFromBufferToBuffer

public static void copyFromBufferToBuffer(ByteBuffer in,
                                          ByteBuffer out,
                                          int sourceOffset,
                                          int destinationOffset,
                                          int length)

Copy from one buffer to another from given offset. This will be absolute positional copying and won't affect the position of any of the buffers.

Parameters:

in -

out -

sourceOffset -

destinationOffset -

length -

copyFromBufferToBuffer

public static void copyFromBufferToBuffer(ByteBuffer in,
                                          ByteBuffer out,
                                          int sourceOffset,
                                          int length)

Copy from one buffer to another from given offset.

Note : This will advance the position marker of out but not change the position maker for in

Parameters:

in - source buffer

out - destination buffer

sourceOffset - offset in the source buffer

length - how many bytes to copy

findCommonPrefix

public static int findCommonPrefix(ByteBuffer buffer,
                                   int offsetLeft,
                                   int offsetRight,
                                   int limit)

Find length of common prefix of two parts in the buffer

Parameters:

buffer - Where parts are located.

offsetLeft - Offset of the first part.

offsetRight - Offset of the second part.

limit - Maximal length of common prefix.

Returns:

Length of prefix.

findCommonPrefix

public static int findCommonPrefix(byte[] left,
                                   int leftOffset,
                                   int leftLength,
                                   byte[] right,
                                   int rightOffset,
                                   int rightLength)

Find length of common prefix in two arrays.

Parameters:

left - Array to be compared.

leftOffset - Offset in left array.

leftLength - Length of left array.

right - Array to be compared.

rightOffset - Offset in right array.

rightLength - Length of right array.

findCommonPrefix

public static int findCommonPrefix(ByteBuffer left,
                                   int leftOffset,
                                   int leftLength,
                                   ByteBuffer right,
                                   int rightOffset,
                                   int rightLength)

Find length of common prefix in two arrays.

Parameters:

left - ByteBuffer to be compared.

leftOffset - Offset in left ByteBuffer.

leftLength - Length of left ByteBuffer.

right - ByteBuffer to be compared.

rightOffset - Offset in right ByteBuffer.

rightLength - Length of right ByteBuffer.

arePartsEqual

public static boolean arePartsEqual(ByteBuffer buffer,
                                    int offsetLeft,
                                    int lengthLeft,
                                    int offsetRight,
                                    int lengthRight)

Check whether two parts in the same buffer are equal.

Parameters:

buffer - In which buffer there are parts

offsetLeft - Beginning of first part.

lengthLeft - Length of the first part.

offsetRight - Beginning of the second part.

lengthRight - Length of the second part.

Returns:

True if equal

skip

public static void skip(ByteBuffer buffer,
                        int length)

Increment position in buffer.

Parameters:

buffer - In this buffer.

length - By that many bytes.

extendLimit

public static void extendLimit(ByteBuffer buffer,
                               int numBytes)

toBytes

public static byte[] toBytes(ByteBuffer buffer,
                             int startPosition)

Copy the bytes from position to limit into a new byte[] of the exact length and sets the position and limit back to their original values (though not thread safe).

Parameters:

buffer - copy from here

startPosition - put buffer.get(startPosition) into byte[0]

Returns:

a new byte[] containing the bytes in the specified range

toBytes

public static byte[] toBytes(ByteBuffer buffer,
                             int offset,
                             int length)

Copy the given number of bytes from specified offset into a new byte[]

Parameters:

buffer -

offset -

length -

Returns:

a new byte[] containing the bytes in the specified range

equals

public static boolean equals(ByteBuffer buf1,
                             int o1,
                             int l1,
                             ByteBuffer buf2,
                             int o2,
                             int l2)

hashCode

public static int hashCode(ByteBuffer buf,
                           int offset,
                           int length)

Parameters:

buf - ByteBuffer to hash

offset - offset to start from

length - length to hash

compareTo

public static int compareTo(ByteBuffer buf1,
                            int o1,
                            int l1,
                            ByteBuffer buf2,
                            int o2,
                            int l2)

equals

public static boolean equals(ByteBuffer buf1,
                             int o1,
                             int l1,
                             byte[] buf2,
                             int o2,
                             int l2)

compareTo

public static int compareTo(byte[] buf1,
                            int o1,
                            int l1,
                            ByteBuffer buf2,
                            int o2,
                            int l2)

compareTo

public static int compareTo(ByteBuffer buf1,
                            int o1,
                            int l1,
                            byte[] buf2,
                            int o2,
                            int l2)

toShort

public static short toShort(ByteBuffer buffer,
                            int offset)

Reads a short value at the given buffer's offset.

Parameters:

buffer -

offset -

Returns:

short value at offset

toInt

public static int toInt(ByteBuffer buffer)

Reads an int value at the given buffer's current position. Also advances the buffer's position

toInt

public static int toInt(ByteBuffer buffer,
                        int offset)

Reads an int value at the given buffer's offset.

Parameters:

buffer -

offset -

Returns:

int value at offset

readAsInt

public static int readAsInt(ByteBuffer buf,
                            int offset,
                            int length)

Converts a ByteBuffer to an int value

Parameters:

buf - The ByteBuffer

offset - Offset to int value

length - Number of bytes used to store the int value.

Returns:

the int value

Throws:

IllegalArgumentException - if there's not enough bytes left in the buffer after the given offset

toLong

public static long toLong(ByteBuffer buffer,
                          int offset)

Reads a long value at the given buffer's offset.

Parameters:

buffer -

offset -

Returns:

long value at offset

putInt

public static void putInt(ByteBuffer buffer,
                          int val)

Put an int value out to the given ByteBuffer's current position in big-endian format. This also advances the position in buffer by int size.

Parameters:

buffer - the ByteBuffer to write to

val - int to write out

putInt

public static int putInt(ByteBuffer buffer,
                         int index,
                         int val)

toDouble

public static double toDouble(ByteBuffer buffer,
                              int offset)

Reads a double value at the given buffer's offset.

Parameters:

buffer -

offset - offset where double is

Returns:

double value at offset

toBigDecimal

public static BigDecimal toBigDecimal(ByteBuffer buffer,
                                      int offset,
                                      int length)

Reads a BigDecimal value at the given buffer's offset.

Parameters:

buffer -

offset -

Returns:

BigDecimal value at offset

putShort

public static void putShort(ByteBuffer buffer,
                            short val)

Put a short value out to the given ByteBuffer's current position in big-endian format. This also advances the position in buffer by short size.

Parameters:

buffer - the ByteBuffer to write to

val - short to write out

putShort

public static int putShort(ByteBuffer buffer,
                           int index,
                           short val)

putAsShort

public static int putAsShort(ByteBuffer buf,
                             int index,
                             int val)

putLong

public static void putLong(ByteBuffer buffer,
                           long val)

Put a long value out to the given ByteBuffer's current position in big-endian format. This also advances the position in buffer by long size.

Parameters:

buffer - the ByteBuffer to write to

val - long to write out

putLong

public static int putLong(ByteBuffer buffer,
                          int index,
                          long val)

copyFromArrayToBuffer

public static void copyFromArrayToBuffer(ByteBuffer out,
                                         byte[] in,
                                         int inOffset,
                                         int length)

Copies the bytes from given array's offset to length part into the given buffer. Puts the bytes to buffer's current position. This also advances the position in the 'out' buffer by 'length'

Parameters:

out -

in -

inOffset -

length -

copyFromArrayToBuffer

public static void copyFromArrayToBuffer(ByteBuffer out,
                                         int outOffset,
                                         byte[] in,
                                         int inOffset,
                                         int length)

Copies bytes from given array's offset to length part into the given buffer. Puts the bytes to buffer's given position. This doesn't affact the position of buffer.

Parameters:

out -

in -

inOffset -

length -

copyFromBufferToArray

public static void copyFromBufferToArray(byte[] out,
                                         ByteBuffer in,
                                         int sourceOffset,
                                         int destinationOffset,
                                         int length)

Copies specified number of bytes from given offset of 'in' ByteBuffer to the array. This doesn't affact the position of buffer.

Parameters:

out -

in -

sourceOffset -

destinationOffset -

length -

copyOfRange

public static byte[] copyOfRange(ByteBuffer original,
                                 int from,
                                 int to)

Similar to Arrays.copyOfRange(byte[], int, int)

Parameters:

original - the buffer from which the copy has to happen

from - the starting index

to - the ending index

Returns:

a byte[] created out of the copy

toStringBinary

public static String toStringBinary(ByteBuffer b,
                                    int off,
                                    int len)

toStringBinary

public static String toStringBinary(ByteBuffer b)