org.apache.iotdb.tsfile.encoding.bitpacking

Class IntPacker

java.lang.Object

org.apache.iotdb.tsfile.encoding.bitpacking.IntPacker

public class IntPacker
extends Object

This class is used to encode(decode) Integer in Java with specified bit-width. User need to guarantee that the length of every given Integer in binary mode is less than or equal to the bit-width.

e.g., if bit-width is 4, then Integer '16'(10000)b is not allowed but '15'(1111)b is allowed.

Constructor Summary

Constructors

Constructor and Description
IntPacker(int width)

Method Summary

Modifier and Type	Method and Description
void	pack8Values(int[] values, int offset, byte[] buf) Encode 8 (NUM_OF_INTS) Integers from the array 'values' with specified bit-width to bytes.
void	setWidth(int width)
void	unpack8Values(byte[] buf, int offset, int[] values) decode Integers from byte array.
void	unpackAllValues(byte[] buf, int length, int[] values) decode all values from 'buf' with specified offset and length decoded result will be saved in the array named 'values'.

Methods inherited from class java.lang.Object

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

Constructor Detail

IntPacker

public IntPacker(int width)

Method Detail

pack8Values

public void pack8Values(int[] values,
                        int offset,
                        byte[] buf)

Encode 8 (NUM_OF_INTS) Integers from the array 'values' with specified bit-width to bytes.

Parameters:

values - - array where '8 Integers' are in

offset - - the offset of first Integer to be encoded

buf - - encoded bytes, buf size must be equal to (NUM_OF_INTS * width / 8)

unpack8Values

public void unpack8Values(byte[] buf,
                          int offset,
                          int[] values)

decode Integers from byte array.

Parameters:

buf - - array where bytes are in.

offset - - offset of first byte to be decoded in buf

values - - decoded result , the length of 'values' should be @{link IntPacker#NUM_OF_INTS}

unpackAllValues

public void unpackAllValues(byte[] buf,
                            int length,
                            int[] values)

decode all values from 'buf' with specified offset and length decoded result will be saved in the array named 'values'.

Parameters:

buf - array where all bytes are in.

length - length of bytes to be decoded in buf.

values - decoded result.

setWidth

public void setWidth(int width)