RandomString

Detailed Description

A class to generate pseudorandom sequences of strings.

Definition at line 11 of file RandomString.java.

Public Member Functions
	RandomString (int length, Random random, String symbols)
	RandomString (int length, Random random)
	RandomString (int length, String symbols)
	RandomString (int length)
String	nextString ()

Static Public Attributes
static final String	UPPER = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
static final String	LOWER = UPPER.toLowerCase(Locale.ROOT)
static final String	DIGITS = "0123456789"
static final String	ALPHANUM = UPPER + LOWER + DIGITS

Private Attributes
final Random	random
final char []	symbols
final char []	buffer

Constructor & Destructor Documentation

RandomString() [1/4]

RandomString	(	int	length,
		Random	random,
		String	symbols
	)

Constructs a new random string generator instance used to create pseudorandom strings.

Parameters

length	the random generated string size
random	the class instance to generate pseudorandom strings
symbols	the string containing all the symbols, that the random strings will be composed of

Definition at line 29 of file RandomString.java.

RandomString() [2/4]

RandomString	(	int	length,
		Random	random
	)

Constructs a new random string generator instance.

The random string will be formed with alphanumeric characters.

Parameters

length	the random generated string size
random	the class instance to generate pseudorandom strings

Definition at line 49 of file RandomString.java.

RandomString() [3/4]

RandomString	(	int	length,
		String	symbols
	)

Constructs a new random string generator instance used to create pseudorandom strings from a secure generator.

Parameters

length	the random generated string size
symbols	the string containing all the symbols, that the random strings will be composed of

Definition at line 59 of file RandomString.java.

RandomString() [4/4]

RandomString

(

int

length

)

Constructs a new random string generator instance used to create pseudorandom strings from a secure generator.

The random string will be formed with alphanumeric characters.

Parameters

length

the random generated string size

See also

SecureRandom

Definition at line 71 of file RandomString.java.

Member Function Documentation

nextString()

String nextString

(

)

Returns a pseudorandom, uniformly distributed.

String 

value, from this random string generator's sequence. The general contract of

nextString 

is that one

String 

value formed with the available symbols is pseudorandomly generated and returned. All possible

String 

values are produced with (approximately) equal probability. The method

nextString 

is implemented using the provided

Random 

class's methods.

The probability of a collision,

p 

, is approximately n²/(2q^x), where

n 

is the number of identifiers actually generated,

q 

is the number of distinct symbols in the alphabet, and

x 

is the length of the generated string. The longer the

String 

is, the lower the probability of a collision taking place is.

Returns

the next pseudorandom, uniformly distributed

String 

value formed with the provided symbols and from this random generator's sequence

See also

Random

Definition at line 92 of file RandomString.java.

Member Data Documentation

UPPER

final String UPPER = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

static

Definition at line 13 of file RandomString.java.

LOWER

final String LOWER = UPPER.toLowerCase(Locale.ROOT)

static

Definition at line 14 of file RandomString.java.

DIGITS

final String DIGITS = "0123456789"

static

Definition at line 15 of file RandomString.java.

ALPHANUM

final String ALPHANUM = UPPER + LOWER + DIGITS

static

Definition at line 16 of file RandomString.java.

random

final Random random

private

Definition at line 18 of file RandomString.java.

symbols

final char [] symbols

private

Definition at line 19 of file RandomString.java.

buffer

final char [] buffer

private

Definition at line 20 of file RandomString.java.