Skip navigation.

Programming WebLogic HTTP Servlets

  Previous Next vertical dots separating previous/next from contents/index/pdf Contents Index View as PDF   Get Adobe Reader

Administration and Configuration

The following sections provide an overview of administration and configuration tasks for WebLogic HTTP servlets. For a complete discussion of servlet administration and configuration see Configuring Servlets.

This section discusses the following topics:


Overview of WebLogic HTTP Servlet Administration

Consistent with the Java 2 Enterprise Edition standard, HTTP servlets are deployed as part of a Web Application. A Web Application is a grouping of application components, such as servlet classes, JavaServer Pages (JSP), static HTML pages, images, and utility classes.

In a Web Application the components are deployed using a standard directory structure. This directory structure can be archived into a file called a .war file and then deployed on WebLogic Server. Information about the resources and operating parameters of a Web Application are defined using two deployment descriptors, which are packaged with the Web Application.

Using Deployment Descriptors to Configure and Deploy Servlets

The first deployment descriptor, web.xml, is defined in the Servlet 2.3 specification from Sun Microsystems and provides a standardized format that describes the Web Application. The second deployment descriptor, weblogic.xml, is a WebLogic-specific deployment descriptor that maps resources defined in the web.xml file to resources available in WebLogic Server, defines JSP behavior, and defines HTTP session parameters.

web.xml (Web Application Deployment Descriptor)

In the Web Application deployment descriptor you define the following attributes for HTTP servlets:

For a complete discussion of creating the web.xml file, see Deployment Descriptors.

weblogic.xml (Weblogic-Specific Deployment Descriptor)

In the WebLogic-specific deployment descriptor you define the following attributes for HTTP servlets:

For a complete discussion of creating the weblogic.xml file, see Writing Web Application Deployment Descriptors.

WebLogic Server Administration Console

Use the WebLogic Server Administration Console to set the following parameters:

For more information see the following resources:


Directory Structure for Web Applications

Use the following directory structure for all Web Applications:

Default WebApp/(Publicly available files, such as
| .jsp, .html, .jpg, .gif)
+ classes/(directory containing
| Java classes including
| servlets used by the
| Web Application)
+ lib/(directory containing
| jar files used by the
| Web Application)
+ web.xml
+ weblogic.xml


Referencing a Servlet in a Web Application

The URL used to reference a servlet in a Web Application is constructed as follows:


The components of this URL are defined as follows:


The DNS name mapped to the Web Server defined in the WebLogic Server Administration Console.

This portion of the URL can be replaced with host:port, where host is the name of the machine running WebLogic Server and port is the port at which WebLogic Server is listening for requests.


The port at which WebLogic Server is listening for requests. The Servlet can communicate with the proxy only through the listenPort on the Server mBean and the SSL mBean.


The name of the context root which is specified in the weblogic.xml file, or the uri of the web module which is specified in the config.xml file.


The name of the servlet as defined in the web.xml file.


Optional HTTP request parameters encoded in the URL, which can be read by an HTTP servlet.

URL Pattern Matching

WebLogic Server provides the user with the ability to implement a URL matching utility which does not conform to the J2EE rules for matching. The utility must be configured in the weblogic.xml deployment descriptor rather than the web.xml deployment descriptor used for the configuration of the default implementation of URLMatchMap.

To be used with WebLogic Server, the URL matching utility must implement the following interface:

Package weblogic.servlet.utils;

public interface URLMapping {

public void put(String pattern, Object value);

public Object get(String uri);

public void remove(String pattern)

public void setDefault(Object defaultObject);

public Object getDefault();

public void setCaseInsensitive(boolean ci);

public boolean isCaseInsensitive();

public int size();

public Object[] values();

public String[] keys();


The SimpleApacheURLMatchMap Utility

The included SimpleApacheURLMatchMap utility is not J2EE specific. It can be configured in the weblogic.xml deployment descriptor file and allows the user to specify Apache style pattern matching rather than the default URL pattern matching provided in the web.xml deployment descriptor.


Servlet Security

Security for servlets is defined in the context of the Web Application containing the servlet. Security can be handled by WebLogic Server, or it can be incorporated programmatically into your servlet classes.

For more information see Securing WebLogic Resourcessecwlres/index.html.


You can incorporate user authentication into your servlets using any of the following three techniques:

The BASIC and FORM techniques call into a security role that contains user and password information. You can use a default role provided with WebLogic Server, or a variety of existing roles, including roles for Windows NT, UNIX, RDBMS, and user-defined roles. For more information about security roles, see Security Fundamentals.

Authorization (Security Constraints)

You can restrict access to servlets and other resources in a Web Application by using security constraints. Security constraints are defined in the Web Application deployment descriptor (web.xml). There are three basic types of security constraints:

Roles can be mapped to a principal. Specific resources can be constrained by matching a URL pattern to a resource in a Web Application. You can also use Secure Sockets Layer (SSL) as a security constraint.

You can perform authorization programmatically, using one of the following methods of the HttpServletRequest interface:

For more information see the javax.servlet API.


Servlet Development Tips

Consider the following tips when writing HTTP servlets:


Clustering Servlets

Clustering servlets provides failover and load balancing benefits. To deploy a servlet in a WebLogic Server cluster, deploy the Web Application containing the servlet on all servers in the cluster. For instructions, see Deploying Applications to a Cluster in Using WebLogic Server Clusters.

For information on requirements for clustering servlets, and to understand the connection and failover processes for requests that are routed to clustered servlets, see Replication and Failover for Servlets and JSPs in Using WebLogic Server Clusters.

Note: Automatic failover for servlets requires that the servlet session state be replicated in memory. For instructions, see Configure In-Memory HTTP Replication in Using WebLogic Server Clusters.

For information on the load balancing support that a WebLogic Server cluster provides for servlets, and for related planning and configuration considerations for architects and administrators, see Load Balancing for Servlets and JSPs in Using WebLogic Server Clusters.


Back to Top Previous Next