The following document illustrates how to get started writing a web application using common code that we have been using or developing over the last few years. We also describe how to deploy the application to a web server.
Web Application Skeleton
Download end extract the following zip file containing a skeleton for your new web application.
Sitemesh
Sitemesh is used to decorate the pages, making sure they all get a similar look and feel. Please refer to the sitemesh documentation for more information.
The main sitemesh related files are the following:
- src/webapp/WEB-INF/sitemesh.xml Sitemes configuration file in which appropriate modules are loaded to handle frames.
- src/webapp/WEB-INF/decorators.xml This is the mapping between your jsp pages and the templates to be used to decorate them. In this example we map all the pages to a common decorator, but for three pages belonging to a frame which need to have special decorators. The following are the decorators used:
-
- src/webapp/decorators/basicDecorator.jsp common decorator for all pages. It adds a common style sheed from the GLAST commons, a style sheet specifit to this application (src/webapp/css/style.css), it adds the logo on the top right of the page, the login button and the footer with the last modified date.
- src/webapp/decorators/justFooterDecorator.jsp decorator that just adds the footer, used for the main window of frames. It adds the last modified date at the bottom of the page.
- src/webapp/decorators/justHeaderDecorator.jsp decorator that just decorates the header with the logo and the login button. This is used for the header of a frame.
- src/webapp/decorators/justStyleDecorator.jsp decorator that just adds style sheets. Used for the menu/tree window of a frame.
The above decorators share common code stored in the form of tag files:
- src/webapp/WEB-INF/tags/decorators/footerDecorator.tag Prints the last modified date in the footer.
- src/webapp/WEB-INF/tags/decorators/headerDecorator.tag Adds the logo and the login button to the header.
Finally for sitemesh to work a filter needs to be added to the application. It's the filter that is responsible for mangling your jsp code with the decorating templates. This is done in src/webapp/WEB-INF/web.xml with the following code:
<filter>
<filter-name>sitemesh</filter-name>
<filter-class>com.opensymphony.module.sitemesh.filter.PageFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>sitemesh</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
If you are not interested in sitemesh you can remove the filter definition in web.xml and all the above files.