org.apache.kafka.common.utils
Class Utils

java.lang.Object
  org.apache.kafka.common.utils.Utils

public class Utils
extends java.lang.Object

Field Summary

static java.lang.String

NL

Constructor Summary

Utils()

Method Summary

static int	abs(int n) Get the absolute value of the given number.
static java.lang.String	formatAddress(java.lang.String host, java.lang.Integer port) Formats hostname and port number as a "host:port" address string, surrounding IPv6 addresses with braces '[', ']'
static java.lang.String	getHost(java.lang.String address) Extracts the hostname from a "host:port" address string.
static java.lang.Integer	getPort(java.lang.String address) Extracts the port number from a "host:port" address string.
static int	murmur2(byte[] data) Generates 32 bit murmur2 hash from byte array
static java.lang.Object	newInstance(java.lang.Class<?> c) Instantiate the class
static <T> T	notNull(T t) Check that the parameter t is not null
static long	readUnsignedInt(java.nio.ByteBuffer buffer) Read an unsigned integer from the current position in the buffer, incrementing the position by 4 bytes
static long	readUnsignedInt(java.nio.ByteBuffer buffer, int index) Read an unsigned integer from the given position without modifying the buffers position
static int	readUnsignedIntLE(byte[] buffer, int offset) Read an unsigned integer stored in little-endian format from a byte array at a given offset.
static int	readUnsignedIntLE(java.io.InputStream in) Read an unsigned integer stored in little-endian format from the InputStream.
static byte[]	toArray(java.nio.ByteBuffer buffer) Read the given byte buffer into a byte array
static byte[]	toArray(java.nio.ByteBuffer buffer, int offset, int size) Read a byte array from the given offset and size in the buffer
static java.lang.String	utf8(byte[] bytes) Turn the given UTF8 byte array into a string
static byte[]	utf8(java.lang.String string) Turn a string into a utf8 byte[]
static int	utf8Length(java.lang.CharSequence s) Get the length for UTF8-encoding a string without encoding it first
static void	writetUnsignedInt(java.nio.ByteBuffer buffer, long value) Write the given long value as a 4 byte unsigned integer.
static void	writeUnsignedInt(java.nio.ByteBuffer buffer, int index, long value) Write the given long value as a 4 byte unsigned integer.
static void	writeUnsignedIntLE(byte[] buffer, int offset, int value) Write an unsigned integer in little-endian format to a byte array at a given offset.
static void	writeUnsignedIntLE(java.io.OutputStream out, int value) Write an unsigned integer in little-endian format to the OutputStream.

Methods inherited from class java.lang.Object

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

Field Detail

NL

public static java.lang.String NL

Constructor Detail

Utils

public Utils()

Method Detail

utf8

public static java.lang.String utf8(byte[] bytes)

Turn the given UTF8 byte array into a string

Parameters:

bytes - The byte array

Returns:

The string

utf8

public static byte[] utf8(java.lang.String string)

Turn a string into a utf8 byte[]

Parameters:

string - The string

Returns:

The byte[]

readUnsignedInt

public static long readUnsignedInt(java.nio.ByteBuffer buffer)

Read an unsigned integer from the current position in the buffer, incrementing the position by 4 bytes

Parameters:

buffer - The buffer to read from

Returns:

The integer read, as a long to avoid signedness

readUnsignedInt

public static long readUnsignedInt(java.nio.ByteBuffer buffer,
                                   int index)

Read an unsigned integer from the given position without modifying the buffers position

Parameters:

buffer - the buffer to read from

index - the index from which to read the integer

Returns:

The integer read, as a long to avoid signedness

readUnsignedIntLE

public static int readUnsignedIntLE(java.io.InputStream in)
                             throws java.io.IOException

Read an unsigned integer stored in little-endian format from the InputStream.

Parameters:

in - The stream to read from

Returns:

The integer read (MUST BE TREATED WITH SPECIAL CARE TO AVOID SIGNEDNESS)

Throws:

java.io.IOException

readUnsignedIntLE

public static int readUnsignedIntLE(byte[] buffer,
                                    int offset)

Read an unsigned integer stored in little-endian format from a byte array at a given offset.

Parameters:

buffer - The byte array to read from

offset - The position in buffer to read from

Returns:

The integer read (MUST BE TREATED WITH SPECIAL CARE TO AVOID SIGNEDNESS)

writetUnsignedInt

public static void writetUnsignedInt(java.nio.ByteBuffer buffer,
                                     long value)

Write the given long value as a 4 byte unsigned integer. Overflow is ignored.

Parameters:

buffer - The buffer to write to

value - The value to write

writeUnsignedInt

public static void writeUnsignedInt(java.nio.ByteBuffer buffer,
                                    int index,
                                    long value)

Write the given long value as a 4 byte unsigned integer. Overflow is ignored.

Parameters:

buffer - The buffer to write to

index - The position in the buffer at which to begin writing

value - The value to write

writeUnsignedIntLE

public static void writeUnsignedIntLE(java.io.OutputStream out,
                                      int value)
                               throws java.io.IOException

Write an unsigned integer in little-endian format to the OutputStream.

Parameters:

out - The stream to write to

value - The value to write

Throws:

java.io.IOException

writeUnsignedIntLE

public static void writeUnsignedIntLE(byte[] buffer,
                                      int offset,
                                      int value)

Write an unsigned integer in little-endian format to a byte array at a given offset.

Parameters:

buffer - The byte array to write to

offset - The position in buffer to write to

value - The value to write

abs

public static int abs(int n)

Get the absolute value of the given number. If the number is Int.MinValue return 0. This is different from java.lang.Math.abs or scala.math.abs in that they return Int.MinValue (!).

utf8Length

public static int utf8Length(java.lang.CharSequence s)

Get the length for UTF8-encoding a string without encoding it first

Parameters:

s - The string to calculate the length for

Returns:

The length when serialized

toArray

public static byte[] toArray(java.nio.ByteBuffer buffer)

Read the given byte buffer into a byte array

toArray

public static byte[] toArray(java.nio.ByteBuffer buffer,
                             int offset,
                             int size)

Read a byte array from the given offset and size in the buffer

notNull

public static <T> T notNull(T t)

Check that the parameter t is not null

Parameters:

t - The object to check

Returns:

t if it isn't null

Throws:

java.lang.NullPointerException - if t is null.

newInstance

public static java.lang.Object newInstance(java.lang.Class<?> c)

Instantiate the class

murmur2

public static int murmur2(byte[] data)

Generates 32 bit murmur2 hash from byte array

Parameters:

data - byte array to hash

Returns:

32 bit hash of the given array

getHost

public static java.lang.String getHost(java.lang.String address)

Extracts the hostname from a "host:port" address string.

Parameters:

address - address string to parse

Returns:

hostname or null if the given address is incorrect

getPort

public static java.lang.Integer getPort(java.lang.String address)

Extracts the port number from a "host:port" address string.

Parameters:

address - address string to parse

Returns:

port number or null if the given address is incorrect

formatAddress

public static java.lang.String formatAddress(java.lang.String host,
                                             java.lang.Integer port)

Formats hostname and port number as a "host:port" address string, surrounding IPv6 addresses with braces '[', ']'

Parameters:

host - hostname

port - port number

Returns:

address string