Java Enterprise in a Nutshell, Second Edition

Name

ServletContext

Synopsis

ServletContext defines methods that allow a servlet to interact with the host server. This includes reading server-specific attributes, finding information about particular files located on the server, and writing to the server log files. The ServletContext also allows creation of RequestDispatcher objects. As of the Servlet 2.2 API, which introduced web applications, the ServletContext has been formalized as a programmatic interface to a web application. Each web application has its own ServletContext, which is shared by all of the servlets configured in the web application. The servlets can use the setAttribute() and getAttribute() methods of the ServletContext to share information throughout a web application.

The getServlet(), getServletNames() and getServlets() methods were deprecated in versions 2.0 and 2.1 of the Servlet API, and have not been directly replaced. Instead of accessing each other directly, servlets should share information via the context attributes.

public interface ServletContext {
// Property Accessor Methods (by property name)
   public abstract java.util.Enumeration getAttributeNames();    // 2.1
   public abstract java.util.Enumeration getInitParameterNames(  // 2.2
        );  
   public abstract int getMajorVersion();                        // 2.1
   public abstract int getMinorVersion();                        // 2.1
   public abstract String getServerInfo();  
   public abstract String getServletContextName();               // 2.3
                  // Public Instance Methods
   public abstract Object getAttribute( String name); public ...