Commons Lang - an extension of the java.lang package

 The Lang Component contains a set of Java classes that provide helper
 methods for standard Java classes, especially those found in the
 java.lang package in the Sun JDK. The following classes are included:
 .
  * StringUtils - Helper for java.lang.String.
  * CharSetUtils - Methods for dealing with CharSets, which are sets of
    characters such as [a-z] and [abcdez].
  * RandomStringUtils - Helper for creating randomised Strings.
  * NumberUtils - Helper for java.lang.Number and its subclasses.
  * NumberRange - A range of numbers with an upper and lower bound.
  * ObjectUtils - Helper for java.lang.Object.
  * SerializationUtils - Helper for serializing Objects.
  * SystemUtils - Utility class defining the Java system properties.
  * NestedException package - A sub-package for the creation of nested
    exceptions.
  * Enum package - A sub-package for the creation of enumerated types.
  * Builder package - A sub-package for the creation of equals, hashCode,
    compareTo and toString methods.