JSP Overview


	BEA Home \| Events \| Solutions \| Partners \| Products \| Services \| Download \| Developer Center \| WebSUPPORT
	http://www.oracle.com/technology/documentation/index.html \| Site Map \| Search \| Download Documentation \| Contact \| Glossary

\| WebLogic Server Doc Home \| WebLogic JSP \| Previous Topic \| Next Topic \| Contents \| Index \| View as PDF

JSP Overview

This document is an introduction and reference for the basic syntax of JavaServer Pages (JSP). It provides information about how to use JSP with WebLogic Server. It is not intended as a comprehensive guide to programming with JSP.

The following sections provide an overview of JSP:

What Is JSP?

JavaServer Pages (JSP) is a Sun Microsystems specification for combining Java with HTML to provide dynamic content for Web pages. When you create dynamic content, JSPs are more convenient to write than HTTP servlets because they allow you to embed Java code directly into your HTML pages, in contrast with HTTP servlets, in which you embed HTML inside Java code. JSP is part of the Java 2 Enterprise Edition (J2EE).

JSP enables you to separate the dynamic content of a Web page from its presentation. It caters to two different types of developers: HTML developers, who are responsible for the graphical design of the page, and Java developers, who handle the development of software to create the dynamic content.

Because JSP is part of the J2EE standard, you can deploy JSPs on a variety of platforms, including WebLogic Server. In addition, third-party vendors and application developers can provide JavaBean components and define custom JSP tags that can be referenced from a JSP page to provide dynamic content.

WebLogic Implementation of JSP

BEA WebLogic JSP supports the JSP 1.1 specification from Sun Microsystems. JSP 1.1 includes support for defining custom JSP tag extensions. (See Programming JSP Extensions)

WebLogic Server also supports the Servlet 2.2 specification from Sun Microsystems, and the proposed final draft of the Servlet 2.3 specification. For more information, see Servlet 2.3.

Note: WebLogic Server version 6.1 supports the JSP 1.2 specification with the following exceptions:

The jsp:id mechanism has not been implemented

The following feature has not been implemented:

A JAR containing a packaged tag libraries can be dropped into the WEB-INF/lib directory to make its classes available at request time

The following DTD Elements are not supported:

The <listener> element in the taglib.tld is not registered with the webapp
The <example> element in the taglib.tld is not honored.
We still use the older signature of the TaglibraryValidator.validate() method which returns a String

The Servlet 2.3 and JSP 1.2 specifications are part of the J2EE 1.3 specification. To use these features, please see WebLogic Server 6.1 with J2EE 1.2 and J2EE 1.3 Functionality.

WebLogic Server 6.1 with J2EE 1.2 and J2EE 1.3 Functionality

BEA WebLogic Server 6.1 is the first e-commerce transaction platform to implement advanced J2EE 1.3 features. To comply with the rules governing J2EE, BEA Systems provides two separate downloads: one with J2EE 1.3 features enabled, and one that is limited to J2EE 1.2 features only. Both downloads offer the same container and differ only in the APIs that are available.

WebLogic Server 6.1 with J2EE 1.2 Plus Additional J2EE 1.3 Features

With this download, WebLogic Server defaults to running with J2EE 1.3 features enabled. These features include EJB 2.0, JSP 1.2, Servlet 2.3, and J2EE Connector Architecture 1.0. When you run WebLogic Server 6.1 with J2EE 1.3 features enabled, J2EE 1.2 applications are still fully supported. The J2EE 1.3 feature implementations use non-final versions of the appropriate API specifications. Therefore, application code developed for BEA WebLogic Server 6.1 that uses the new features of J2EE 1.3 may be incompatible with the J2EE 1.3 platform supported in future releases of BEA WebLogic Server.

WebLogic Server 6.1 with J2EE 1.2 Certification

With this download, WebLogic Server defaults to running with J2EE 1.3 features disabled and is fully compliant with the J2EE 1.2 specification and regulations.

How JSP Requests Are Handled

WebLogic Server handles JSP requests in the following sequence:

A browser requests a page with a .jsp file extension from WebLogic Server.
WebLogic Server reads the request.
Using the JSP compiler, WebLogic Server converts the JSP into a servlet class that implements the javax.servlet.jsp.JspPage interface. The JSP file is compiled only when the page is first requested, or when the JSP file has been changed. Otherwise, the previously compiled JSP servlet class is re-used, making subsequent responses much quicker.
The generated JspPage servlet class is invoked to handle the browser request.

It is also possible to invoke the JSP compiler directly without making a request from a browser. For details, see Using the WebLogic JSP Compiler. Because the JSP compiler creates a Java servlet as its first step, you can look at the Java files it produces, or even register the generated JspPage servlet class as an HTTP servlet.

Additional Information