InfoCenter Home >
4: Developing applications >
4.2: Building Web applications >
4.2.2: Developing JSP files >
4.2.2.3: Overview of JSP file content
4.2.2.3: Overview of JSP file content
JSP files have the extension .jsp. A JSP file
contains any combination of the following items. Click an item to
learn about its syntax. To learn how to put it all together, see
the Related information for examples, samples, and additional
syntax references.
Syntax format |
Details |
Directives |
Use JSP directives (enclosed within <%@ and %>) to specify:
- Scripting language being used
- Interfaces a servlet implements
- Classes a servlet extends
- Packages a servlet imports
- MIME type of the generated response
See Sun's JSP Syntax Reference
for JSP 1.1 syntax descriptions and examples.
|
Class-wide variable and method declarations |
Use the <%! declaration(s) %> syntax to declare
class-wide variables and class-wide methods for the servlet class.
|
Inline Java code (scriptlets), enclosed within <% and %> |
You can embed any valid Java language code inline within
a JSP file between the <% and %> tags. Such
embedded code is called a scriptlet. If you do not specify the method directive, the generated code becomes the body of the service method.
An advantage of embedding Java coding inline in JSP files is that the servlet does not have to be compiled in advance, and placed on the server. This
makes it easier to quickly test servlet coding.
|
Variable text, specified using IBM extensions for variable data
(JSP .91 or JSP 1.0)
or Java expressions enclosed within <%= and %> |
The IBM extensions are the more user-friendly approach to
putting variable fields on your HTML pages.
A second method for adding variable data is to specify a Java language
expression that is resolved when the JSP file is processed. Use the JSP
expression tags <%= and %>. The expression is evaluated,
converted into a string, and displayed. Primitive types, such as int and float, are
automatically converted to string representation.
|
<BEAN> tag |
Use the
<BEAN> tag to create an instance of a bean that will be accessed elsewhere within the JSP file.
Then use JSP tags to access the bean. |
JSP tags for database access
(JSP .91) or
(JSP 1.1)
|
The IBM extensions
make it easy for non-programmers to create Web pages
that access databases.
|
HTML tags
A JSP file can contain any valid HTML tags. View article 0.70: What is HTML? for more information
on HTML. Refer to your favorite HTML
reference for a description of HTML tags.
<SERVLET> tags
Using the <SERVLET> tag is one method for embedding a servlet
within a JSP file.
NCSA tags
You might have legacy SHTML files that contain NCSA tags for server-side
includes. If the IBM WebSphere Application Server Version 3.5 supports the NCSA
tags in your SHTML files, you can convert the SHTML files to JSP files and
retain the NCSA tags.
|
|