Java Servlets
The Java™ Servlet API is a standard extension to Java that extends the functionality of a web server. Java servlets run as Java EE (Enterprise Edition) web containers within a Java EE-compliant web server.
Uniface provides two servlets, which handle HTTP and SOAP requests received by the web server and dispatch them to the Uniface Web Application Server via the Uniface Router:
- WRD—Uniface Web Request Dispatcher for HTTP requests for Uniface web applications
- SRD—Uniface SOAP Request Dispatcher for SOAP requests for Uniface web services
The Java EE-compliant web server handles a pool of servlet instances and typically limits their number. All Uniface servlet instances communicate with the Uniface Router that handles the Uniface Server pools.
The Uniface servlets are delivered in the Java archive file wrd.jar.
Servlet Configuration
To configure a servlet, you should be aware of the following:
- The Java Virtual Machine must know where the
servlet .jar file is located. This information is normally provided in
CLASSPATHenvironment variable, but some servlet engines provide their own way to specify the location. - The web server must know that the servlet
exists. This can be specified in a ASCII file or through a GUI, depending on the servlet engine.
For example, the complete name of the Uniface WRD servlet is
com.compuware.uniface.urd.WRDServlet. - To operate correctly, a servlet needs some parameters to be set. In the case of the WRD servlet and the SRD servlet, there are several mandatory and optional configuration parameters that you can specify. These settings can be defined in an ASCII file or through a GUI, depending on the servlet engine.
