JSTL is developed under the Java Community Process, in the JSR-052 expert group. The purpose of JSTL is to work towards a common and standard set of custom tags.
encapsulates simple tags as the common core functionality to many Web
applications. It also provides a framework for integrating existing custom
tags with JSTL tags.
A tag library is a set of actions that are used within JSP pages. It encapsulates a wide variety of functionality that can be broken down into specific functional areas. JSTL is a single taglib, which is exposed through multiple Tag Library Descriptors (TLDs) where each TLD can have its own namespace, or prefix.
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