||Contains information about an error, for error pages.
JspContext serves as the base class for the
PageContext class and abstracts all information that is not specific
||The JspEngineInfo is an abstract class that provides information on the
current JSP engine.
The JspFactory is an abstract class that defines a number of factory
methods available to a JSP page at runtime for the purposes of creating
instances of various interfaces and classes used to support the JSP
The actions and template data in a JSP page is written using the
JspWriter object that is referenced by the implicit variable out which
is initialized automatically using methods in the PageContext object.
PageContext extends JspContext to provide useful context information for
when JSP technology is used in a Servlet environment.