-------------------
Apache Commons Lang
-------------------

"The standard Java libraries fail to provide enough methods for manipulation of
its core classes. The Lang Component provides these extra methods. The Lang 
Component provides a host of helper utilities for the java.lang API, notably 
String manipulation methods, basic numerical methods, object reflection, 
creation and serialization, and System properties. Additionally it contains 
an inheritable enum type, an exception structure that supports multiple types 
of nested-Exceptions, basic enhancements to java.util.Date and a series of 
utlities dedicated to help with building methods, such as hashCode, toString 
and equals."

For more information:
http://commons.apache.org/lang/