This method is intended to process an unhandled "page" level exception
by redirecting the exception to either the specified error page for this
JSP, or if none was specified, to perform some implementation dependent
The initialize method is called to initialize an uninitialized PageContext
so that it may be used by a JSP Implementation class to service an
incoming request and response within it's _jspService() method.
The javax.servlet.jsp package contains a number of classes and
interfaces that describe and define the contracts between a JSP page
implementation class and the runtime environment provided for an
instance of such a class by a conforming JSP container.
Constructs a new JSP exception when the JSP
needs to throw an exception and include a message
about the "root cause" exception that interfered with its
normal operation, including a description message.
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.