org.apache.cassandra.utils
Class FBUtilities

java.lang.Object
  org.apache.cassandra.utils.FBUtilities

public class FBUtilities
extends java.lang.Object

Field Summary

static int	MAX_UNSIGNED_SHORT
static java.math.BigInteger	TWO

Constructor Summary

FBUtilities()

Method Summary

static long	absoluteFromFraction(double fractOrAbs, long total)
static void	atomicSetMax(java.util.concurrent.atomic.AtomicInteger atomic, int i)
static void	atomicSetMax(java.util.concurrent.atomic.AtomicLong atomic, long i)
static java.lang.String	bytesToHex(byte... bytes)
static <T> java.lang.Class<T>	classForName(java.lang.String classname, java.lang.String readable)
static int	compareUnsigned(byte[] bytes1, byte[] bytes2, int offset1, int offset2, int len1, int len2)
static <T> T	construct(java.lang.String classname, java.lang.String readable) Constructs an instance of the given class, which must have a no-arg constructor.
static void	copyIntoBytes(byte[] bytes, int offset, int i) Copy bytes from int into bytes starting from offset.
static void	copyIntoBytes(byte[] bytes, int offset, long l) Copy bytes from long into bytes starting from offset.
static void	deserialize(org.apache.thrift.TDeserializer deserializer, org.apache.thrift.TBase struct, java.io.DataInput in)
static int	encodedUTF8Length(java.lang.String st)
static org.apache.commons.collections.iterators.CollatingIterator	getCollatingIterator()
static java.net.InetAddress	getLocalAddress()
static java.lang.reflect.Field	getProtectedField(java.lang.Class klass, java.lang.String fieldName) Used to get access to protected/private field of the specified class
static java.lang.String	getReleaseVersionString()
static byte[]	hash(java.nio.ByteBuffer... data)
static java.math.BigInteger	hashToBigInteger(java.nio.ByteBuffer data)
static byte[]	hexToBytes(java.lang.String str)
static Pair<java.math.BigInteger,java.lang.Boolean>	midpoint(java.math.BigInteger left, java.math.BigInteger right, int sigbits) Given two bit arrays represented as BigIntegers, containing the given number of significant bits, calculate a midpoint.
static IRowCacheProvider	newCacheProvider(java.lang.String cache_provider)
static java.security.MessageDigest	newMessageDigest(java.lang.String algorithm)
static IPartitioner	newPartitioner(java.lang.String partitionerClassName)
static double	parseDoubleOrPercent(java.lang.String value) Parses a string representing either a fraction, absolute value or percentage.
static void	renameWithConfirm(java.lang.String tmpFilename, java.lang.String filename)
static java.lang.String	resourceToFile(java.lang.String filename)
static void	serialize(org.apache.thrift.TSerializer serializer, org.apache.thrift.TBase struct, java.io.DataOutput out)
static <T extends java.lang.Comparable> java.util.SortedSet<T>	singleton(T column)
static void	sortSampledKeys(java.util.List<DecoratedKey> keys, Range range)
static java.security.MessageDigest	threadLocalMD5Digest()
static long	timestampMicros()
static byte[]	toByteArray(int i)
static byte[]	toByteArray(long l)
static java.lang.String	toString(java.util.Map<?,?> map)
static void	waitOnFutures(java.lang.Iterable<java.util.concurrent.Future<?>> futures)
static byte[]	xor(byte[] left, byte[] right)

Methods inherited from class java.lang.Object

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

Field Detail

TWO

public static final java.math.BigInteger TWO

MAX_UNSIGNED_SHORT

public static final int MAX_UNSIGNED_SHORT

See Also:

Constant Field Values

Constructor Detail

FBUtilities

public FBUtilities()

Method Detail

threadLocalMD5Digest

public static java.security.MessageDigest threadLocalMD5Digest()

newMessageDigest

public static java.security.MessageDigest newMessageDigest(java.lang.String algorithm)

parseDoubleOrPercent

public static double parseDoubleOrPercent(java.lang.String value)

Parses a string representing either a fraction, absolute value or percentage.

getLocalAddress

public static java.net.InetAddress getLocalAddress()

absoluteFromFraction

public static long absoluteFromFraction(double fractOrAbs,
                                        long total)

Parameters:

fractOrAbs - A double that may represent a fraction or absolute value.

total - If fractionOrAbs is a fraction, the total to take the fraction from

Returns:

An absolute value which may be larger than the total.

midpoint

public static Pair<java.math.BigInteger,java.lang.Boolean> midpoint(java.math.BigInteger left,
                                                                    java.math.BigInteger right,
                                                                    int sigbits)

Given two bit arrays represented as BigIntegers, containing the given number of significant bits, calculate a midpoint.

Parameters:

left - The left point.

right - The right point.

sigbits - The number of bits in the points that are significant.

Returns:

A midpoint that will compare bitwise halfway between the params, and a boolean representing whether a non-zero lsbit remainder was generated.

copyIntoBytes

public static void copyIntoBytes(byte[] bytes,
                                 int offset,
                                 int i)

Copy bytes from int into bytes starting from offset.

Parameters:

bytes - Target array

offset - Offset into the array

i - Value to write

toByteArray

public static byte[] toByteArray(int i)

Parameters:

i - Write this int to an array

Returns:

4-byte array containing the int

copyIntoBytes

public static void copyIntoBytes(byte[] bytes,
                                 int offset,
                                 long l)

Copy bytes from long into bytes starting from offset.

Parameters:

bytes - Target array

offset - Offset into the array

l - Value to write

toByteArray

public static byte[] toByteArray(long l)

Parameters:

l - Write this long to an array

Returns:

8-byte array containing the long

compareUnsigned

public static int compareUnsigned(byte[] bytes1,
                                  byte[] bytes2,
                                  int offset1,
                                  int offset2,
                                  int len1,
                                  int len2)

xor

public static byte[] xor(byte[] left,
                         byte[] right)

Returns:

The bitwise XOR of the inputs. The output will be the same length as the longer input, but if either input is null, the output will be null.

hashToBigInteger

public static java.math.BigInteger hashToBigInteger(java.nio.ByteBuffer data)

hash

public static byte[] hash(java.nio.ByteBuffer... data)

hexToBytes

public static byte[] hexToBytes(java.lang.String str)

bytesToHex

public static java.lang.String bytesToHex(byte... bytes)

renameWithConfirm

public static void renameWithConfirm(java.lang.String tmpFilename,
                                     java.lang.String filename)
                              throws java.io.IOException

Throws:

java.io.IOException

getCollatingIterator

public static org.apache.commons.collections.iterators.CollatingIterator getCollatingIterator()

atomicSetMax

public static void atomicSetMax(java.util.concurrent.atomic.AtomicInteger atomic,
                                int i)

atomicSetMax

public static void atomicSetMax(java.util.concurrent.atomic.AtomicLong atomic,
                                long i)

serialize

public static void serialize(org.apache.thrift.TSerializer serializer,
                             org.apache.thrift.TBase struct,
                             java.io.DataOutput out)
                      throws java.io.IOException

Throws:

java.io.IOException

deserialize

public static void deserialize(org.apache.thrift.TDeserializer deserializer,
                               org.apache.thrift.TBase struct,
                               java.io.DataInput in)
                        throws java.io.IOException

Throws:

java.io.IOException

sortSampledKeys

public static void sortSampledKeys(java.util.List<DecoratedKey> keys,
                                   Range range)

encodedUTF8Length

public static int encodedUTF8Length(java.lang.String st)

resourceToFile

public static java.lang.String resourceToFile(java.lang.String filename)
                                       throws ConfigurationException

Throws:

ConfigurationException

getReleaseVersionString

public static java.lang.String getReleaseVersionString()

timestampMicros

public static long timestampMicros()

waitOnFutures

public static void waitOnFutures(java.lang.Iterable<java.util.concurrent.Future<?>> futures)

newPartitioner

public static IPartitioner newPartitioner(java.lang.String partitionerClassName)
                                   throws ConfigurationException

Throws:

ConfigurationException

classForName

public static <T> java.lang.Class<T> classForName(java.lang.String classname,
                                                  java.lang.String readable)
                                       throws ConfigurationException

Parameters:

classname - Fully qualified classname.

readable - Descriptive noun for the role the class plays.

Returns:

The Class for the given name.

Throws:

ConfigurationException - If the class cannot be found.

construct

public static <T> T construct(java.lang.String classname,
                              java.lang.String readable)
                   throws ConfigurationException

Constructs an instance of the given class, which must have a no-arg constructor.

Parameters:

classname - Fully qualified classname.

readable - Descriptive noun for the role the class plays.

Throws:

ConfigurationException - If the class cannot be found.

singleton

public static <T extends java.lang.Comparable> java.util.SortedSet<T> singleton(T column)

toString

public static java.lang.String toString(java.util.Map<?,?> map)

getProtectedField

public static java.lang.reflect.Field getProtectedField(java.lang.Class klass,
                                                        java.lang.String fieldName)

Used to get access to protected/private field of the specified class

Parameters:

klass - - name of the class

fieldName - - name of the field

Returns:

Field or null on error

newCacheProvider

public static IRowCacheProvider newCacheProvider(java.lang.String cache_provider)
                                          throws ConfigurationException

Throws:

ConfigurationException