The JSP Standard Tag Library (JSTL), version 1.0, introduced the concept of an Expression Language (EL), whose main goal is to provide page authors with an easy way to access and manipulate application data without requiring the use of scriptlets
JSP 2.0 adopted the EL specification from JSTL, and expanded its scope: EL expressions are no longer limited to JSTL action attributes, but may be used in any standard or custom action attribute declared to accept a runtime expression. In addition, EL expressions may now also be used directly in template text outside of any actions. JSP 2.0 also added an important feature to the EL specification: EL functions, which allow page authors to invoke static methods in Java classes from EL expressions. Additionally, JSP 2.0 allows programmatic access and customization of the EL evaluator through a set of standard interfaces and abstract classes.
TheRelease Notes document the new features and bug fixes that have beenincluded in the latest release.
TheJavaDoc API documents for the latest release are available online. In particular, you should read the package overview of theorg.apache.commons.el package.