JSP Tag Libraries is the collection of standard tags. JSP tags are the Java components that can be used in a JSP file. JSP tag libraries allow us to make Java APIs or frameworks available to Web designers, move Java code outside of existing JSP pages, reduce Web development and maintenance costs, develop Web applications easier and faster, and reuse your Java code in multiple Web applications. JavaServer Pages (JSP) tag libraries declares modular functionality so that any JSP page can reuse it. Tag libraries shorten the necessity to embed large amounts of Java code in JSP pages by moving the functionality of the tags into tag implementation classes. Tag libraries includes a specific type of library known as Java Server Pages Tag Library(JSTL).
The JavaServer Pages Standard Tag Library (JSTL) is the collection of the components of the Java EE Web application development platform. JSTL adds a tag library of JSP by extending the JSP specification to perform common tasks, such as XML data processing, conditional execution, loops and internationalization. JSTL provides an better way to embed logic without using embedded Java code directly within a JSP page. Use of a standardized tag set, rather than breaking in and out of Java code leads to more maintainable code and enables separation of concerns between the development of the application code and user interface.
To know more about JSTL click on the link: http:/www.roseindia.net/jstl/introduction.shtml
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