JSTL (JSP Standard Tag Libraries) is a collection of JSP custom tags developed by Java Community Process. The reference implementation is developed by the Jakarta project.
The latest version of JSTL is JSTL 1.1, which requires a JSP container that supports the Java Servlet 2.4 and JavaServer Pages 2.0 specifications.
The goal of JSTL is to help simplify JavaServer Pages page authors' lives. To achieve this goal, JSTL has provided custom tags for many common JSP page authoring tasks that require scripting statements to manipulate server side dynamic data.
JSTL offers tags through 4 libraries:
core - Basic scripting functions
xml - XML processing
fmt - Internationalization of formatting
sql - Data base accessing
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