Package com.atlassian.crowd.util

Class SecureRandomStringUtils

java.lang.Object

com.atlassian.crowd.util.SecureRandomStringUtils

public class SecureRandomStringUtils
extends Object

Generates random Strings by selecting characters from an alphabet using a cryptographically secure PRNG. Methods on this class are thread-safe.

Method Summary

Modifier and Type	Method	Description
static SecureRandomStringUtils	getInstance()
String	randomAlphanumericString(int length)	Generates a random String by randomly selecting characters from the the alphabet of characters in the range 0-9, A-Z and a-z.
String	randomString(int length, char[] alphabet)	Generates a random String by randomly selecting characters from the provided alphabet until the desired length is reached.

Methods inherited from class java.lang.Object

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

Method Details

getInstance

public static SecureRandomStringUtils getInstance()

Returns:

shared instance of SecureRandomStringUtils.

randomString

public String randomString(int length,
 char[] alphabet)

Generates a random String by randomly selecting characters from the provided alphabet until the desired length is reached.

The method for selecting a random character is specified by the implementation.

Unicode surrogate-pairing is not supported. All the provided characters should be in the Unicode BMP, if you wish to avoid generating Strings with invalid UTF-16 surrogates.

Parameters:

length - desired length of random String. Must be positive.

alphabet - collection of characters to select from. Must contain at least one character.

Returns:

String of length length, composed of characters from the supplied alphabet.

randomAlphanumericString

public String randomAlphanumericString(int length)

Generates a random String by randomly selecting characters from the the alphabet of characters in the range 0-9, A-Z and a-z.

The method for selecting a random character is specified by the implementation.

Parameters:

length - desired length of random String.

Returns:

alphanumeric String of length length.

See Also:

• randomString(int, char[])