io.snappydata.test.hydra

Class GsRandom

java.lang.Object

java.util.Random

io.snappydata.test.hydra.GsRandom

All Implemented Interfaces:

java.io.Serializable

public class GsRandom
extends java.util.Random
implements java.io.Serializable

This is a simple extension of java.util.Random that allows for the generation of random numbers within ranges. It also allows for the generation of random strings (within ranges as well).

Since:

JDK1.0

See Also:

Math.random(), Random, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected static java.lang.String	ourString ourString is a privately held instance of a String with with some junk characters

Constructor Summary

Constructors

Constructor and Description
GsRandom() Creates a new random number generator.
GsRandom(long seed) Creates a new random number generator using a single long seed.

Method Summary

Modifier and Type	Method and Description
boolean	nextBoolean() Returns the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence
byte	nextByte() Returns the next pseudorandom, uniformly distributed byte value from this random number generator's sequence
char	nextChar() Returns the next pseudorandom, uniformly distributed char value from this random number generator's sequence There is a hack here to prevent '}' so as to eliminate the possiblity of generating a sequence which would falsely get marked as a suspect string while we are matching the pattern {[0-9]+}.
java.util.Date	nextDate() Returns a random Date.
double	nextDouble(double max) Returns the next pseudorandom, uniformly distributed double value from this random number generator's sequence within a range from 0 to max.
double	nextDouble(double min, double max) Returns the next pseudorandom, uniformly distributed double value from this random number generator's sequence within a range from min to max.
int	nextInt(int max) Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence within a range from 0 to max (inclusive -- which is different from Random.nextInt()).
int	nextInt(int min, int max) Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence within a range from min to max.
long	nextLong(long max) Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence within a range from 0 to max.
long	nextLong(long min, long max) Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence within a range from min to max.
short	nextShort()
java.lang.Object	randomElement(java.util.Vector vec) Returns a randomly-selected element of Vector vec.
java.lang.String	randomReadableString(int max) Like randomString(), but returns only readable characters.
java.lang.String	randomString() Returns a random subset of a pregenerated string.
java.lang.String	randomString(int max) Returns a bounded random subset of a pregenerated large string.

Methods inherited from class java.util.Random

doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, next, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextLong, setSeed

Methods inherited from class java.lang.Object

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

Field Detail

ourString

protected static java.lang.String ourString

ourString is a privately held instance of a String with with some junk characters

Constructor Detail

GsRandom

public GsRandom()

Creates a new random number generator. Its seed is initialized to a value based on the current time.

See Also:

System.currentTimeMillis(), Random.Random()

GsRandom

public GsRandom(long seed)

Creates a new random number generator using a single long seed.

Parameters:

seed - the initial seed.

See Also:

Random.Random(long)

Method Detail

nextBoolean

public boolean nextBoolean()

Returns the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence

Overrides:

nextBoolean in class java.util.Random

Returns:

the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence.

nextChar

public char nextChar()

Returns the next pseudorandom, uniformly distributed char value from this random number generator's sequence There is a hack here to prevent '}' so as to eliminate the possiblity of generating a sequence which would falsely get marked as a suspect string while we are matching the pattern {[0-9]+}. https://svn.gemstone.com/trac/gemfire/ticket/40415

Returns:

the next pseudorandom, uniformly distributed char value from this random number generator's sequence.

nextByte

public byte nextByte()

Returns the next pseudorandom, uniformly distributed byte value from this random number generator's sequence

Returns:

the next pseudorandom, uniformly distributed byte value from this random number generator's sequence.

nextDouble

public double nextDouble(double max)

Returns the next pseudorandom, uniformly distributed double value from this random number generator's sequence within a range from 0 to max.

Parameters:

max - the maximum range (inclusive) for the pseudorandom.

Returns:

the next pseudorandom, uniformly distributed double value from this random number generator's sequence.

nextDouble

public double nextDouble(double min,
                         double max)

Returns the next pseudorandom, uniformly distributed double value from this random number generator's sequence within a range from min to max.

Parameters:

min - the minimum range (inclusive) for the pseudorandom.

max - the maximum range (inclusive) for the pseudorandom.

Returns:

the next pseudorandom, uniformly distributed double value from this random number generator's sequence.

nextShort

public short nextShort()

nextLong

public long nextLong(long max)

Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence within a range from 0 to max.

Parameters:

max - the maximum range (inclusive) for the pseudorandom.

Returns:

the next pseudorandom, uniformly distributed long value from this random number generator's sequence.

nextLong

public long nextLong(long min,
                     long max)

Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence within a range from min to max.

Parameters:

min - the minimum range (inclusive) for the pseudorandom.

max - the maximum range (inclusive) for the pseudorandom.

Returns:

the next pseudorandom, uniformly distributed long value from this random number generator's sequence.

nextInt

public int nextInt(int max)

Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence within a range from 0 to max (inclusive -- which is different from Random.nextInt()).

Overrides:

nextInt in class java.util.Random

Parameters:

max - the maximum range (inclusive) for the pseudorandom.

Returns:

the next pseudorandom, uniformly distributed int value from this random number generator's sequence.

nextInt

public int nextInt(int min,
                   int max)

Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence within a range from min to max. If max < min, returns 0 .

Parameters:

min - the minimum range (inclusive) for the pseudorandom.

max - the maximum range (inclusive) for the pseudorandom.

Returns:

the next pseudorandom, uniformly distributed int value from this random number generator's sequence.

nextDate

public java.util.Date nextDate()

Returns a random Date.

Returns:

A random Date.

randomElement

public java.lang.Object randomElement(java.util.Vector vec)

Returns a randomly-selected element of Vector vec.

randomString

public java.lang.String randomString()

Returns a random subset of a pregenerated string. Both the length and offset of the string are pseudorandom values.

Returns:

a random subset of a pregenerated string.

randomString

public java.lang.String randomString(int max)

Returns a bounded random subset of a pregenerated large string. The length can be no longer than max. max must be no longer than the length of the pregenerated string.

Parameters:

max - the maximum length of the random string to generate.

Returns:

a bounded random string with a length between 0 and max length inclusive.

randomReadableString

public java.lang.String randomReadableString(int max)

Like randomString(), but returns only readable characters.