Installation guide

CHAPTER 8 New Features in EAServer 4.0
What’s New 75
JSP 1.2 support
EAServer 4.0 supports the JSP 1.2 specification. JSP 1.2 extends JSP 1.1 in a
number of ways:
• Uses Servlet 2.3 as the foundation for its semantics.
• Defines the XML syntax for JSP pages.
• Provides for translation-time validation of JSP pages. A new compilation
phase has been added that gives custom tag libraries the opportunity to
examine an XML view of the parsed page, and throw a translation time
exception if problems are detected.
• The ability for tag libraries to include event listener classes. The listeners
are listed in the tag library descriptor and the JSP container automatically
instantiates the listener classes and registers them in a similar way to
web.xml. Essentially, the mechanism locates the type-library descriptors
(TLDs) in the Web Application (either in WEB-INF/classes or WEB-
INF/lib), reads their
<listener> elements, and regards them as an
extension of those listed in web.xml.
• Better specification of the tag handler contract – tag handlers are Java
classes that implement specific servlet interfaces. JSP 1.2 introduces some
new interfaces and changes some existing interfaces to provide better
support.
• Improvements on authoring support – extends tag library functionality.
• Better I18N support – implements the
javax.servlet.ServletResponse.setContentType() method to
provide support for dynamic content-type.
• Fixes the “flush before you include” limitation in JSP 1.1.
For information on creating JSPs in EAServer, see Chapter 24, “Creating
JavaServer Pages,” in the EAServer Programmer’s Guide.
Standard extensions
In accord with the Servlet 2.3 specification, EAServer allows you to install
extensions and define the extensions required by a Web application. If you
import a Web application (in WAR format) that requires extensions that are not
installed, EAServer Manager warns you of the unfulfilled dependencies. For
more information, see Chapter 21, “Creating Web Applications,” in the
EAServer Programmer’s Guide