parquet.bytes

Class BytesUtils

java.lang.Object

parquet.bytes.BytesUtils

public class BytesUtils
extends Object

utility methods to deal with bytes

Author:

Julien Le Dem

Field Summary

Fields

Modifier and Type	Field and Description
static Charset	UTF8

Constructor Summary

Constructors

Constructor and Description
BytesUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static int	getWidthFromMaxInt(int bound) give the number of bits needed to encode an int given the max value
static int	paddedByteCountFromBits(int bitLength)
static int	readIntLittleEndian(byte[] in, int offset) reads an int in little endian at the given position
static int	readIntLittleEndian(InputStream in)
static int	readIntLittleEndianOnOneByte(InputStream in)
static int	readIntLittleEndianOnThreeBytes(InputStream in)
static int	readIntLittleEndianOnTwoBytes(InputStream in)
static int	readIntLittleEndianPaddedOnBitWidth(InputStream in, int bitWidth)
static int	readUnsignedVarInt(InputStream in)
static int	readZigZagVarInt(InputStream in) uses a trick mentioned in https://developers.google.com/protocol-buffers/docs/encoding to read zigZag encoded data
static void	writeIntLittleEndian(OutputStream out, int v)
static void	writeIntLittleEndianOnOneByte(OutputStream out, int v)
static void	writeIntLittleEndianOnThreeBytes(OutputStream out, int v)
static void	writeIntLittleEndianOnTwoBytes(OutputStream out, int v)
static void	writeIntLittleEndianPaddedOnBitWidth(OutputStream out, int v, int bitWidth) Write a little endian int to out, using the the number of bytes required by bit width
static void	writeUnsignedVarInt(int value, OutputStream out)
static void	writeZigZagVarInt(int intValue, OutputStream out)

Methods inherited from class java.lang.Object

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

Field Detail

UTF8

public static final Charset UTF8

Constructor Detail

BytesUtils

public BytesUtils()

Method Detail

getWidthFromMaxInt

public static int getWidthFromMaxInt(int bound)

give the number of bits needed to encode an int given the max value

Parameters:

bound - max int that we want to encode

Returns:

the number of bits required

readIntLittleEndian

public static int readIntLittleEndian(byte[] in,
                      int offset)
                               throws IOException

reads an int in little endian at the given position

Parameters:

in -

offset -

Returns:

Throws:

IOException

readIntLittleEndian

public static int readIntLittleEndian(InputStream in)
                               throws IOException

Throws:

IOException

readIntLittleEndianOnOneByte

public static int readIntLittleEndianOnOneByte(InputStream in)
                                        throws IOException

Throws:

IOException

readIntLittleEndianOnTwoBytes

public static int readIntLittleEndianOnTwoBytes(InputStream in)
                                         throws IOException

Throws:

IOException

readIntLittleEndianOnThreeBytes

public static int readIntLittleEndianOnThreeBytes(InputStream in)
                                           throws IOException

Throws:

IOException

readIntLittleEndianPaddedOnBitWidth

public static int readIntLittleEndianPaddedOnBitWidth(InputStream in,
                                      int bitWidth)
                                               throws IOException

Throws:

IOException

writeIntLittleEndianOnOneByte

public static void writeIntLittleEndianOnOneByte(OutputStream out,
                                 int v)
                                          throws IOException

Throws:

IOException

writeIntLittleEndianOnTwoBytes

public static void writeIntLittleEndianOnTwoBytes(OutputStream out,
                                  int v)
                                           throws IOException

Throws:

IOException

writeIntLittleEndianOnThreeBytes

public static void writeIntLittleEndianOnThreeBytes(OutputStream out,
                                    int v)
                                             throws IOException

Throws:

IOException

writeIntLittleEndian

public static void writeIntLittleEndian(OutputStream out,
                        int v)
                                 throws IOException

Throws:

IOException

writeIntLittleEndianPaddedOnBitWidth

public static void writeIntLittleEndianPaddedOnBitWidth(OutputStream out,
                                        int v,
                                        int bitWidth)
                                                 throws IOException

Write a little endian int to out, using the the number of bytes required by bit width

Throws:

IOException

readUnsignedVarInt

public static int readUnsignedVarInt(InputStream in)
                              throws IOException

Throws:

IOException

readZigZagVarInt

public static int readZigZagVarInt(InputStream in)
                            throws IOException

uses a trick mentioned in https://developers.google.com/protocol-buffers/docs/encoding to read zigZag encoded data

Parameters:

in -

Returns:

Throws:

IOException

writeUnsignedVarInt

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

Throws:

IOException

writeZigZagVarInt

public static void writeZigZagVarInt(int intValue,
                     OutputStream out)
                              throws IOException

Throws:

IOException

paddedByteCountFromBits

public static int paddedByteCountFromBits(int bitLength)

Parameters:

bitLength - a count of bits

Returns:

the corresponding byte count padded to the next byte