Java Servlet Programming

Name

Servlet

Synopsis

Interface Name: javax.servlet.Servlet

Super-interface: None

Immediate Subinterfaces: None

Implemented By: javax.servlet.GenericServlet

Availability: Servlet API 1.0 and later

Description

All servlets implement the Servlet interface, either directly or by subclassing the GenericServlet or HttpServlet class. Most servlet developers find it easier to subclass one of the two existing servlet classes than to implement this interface directly. The interface declares the basic servlet functionality—initializing a servlet, handling a client request, and destroying a servlet.

Interface Declaration

public interface Servlet {
  // Methods
  public abstract void destroy();
  public abstract ServletConfig getServletConfig();
  public abstract String getServletInfo();
  public abstract void init(ServletConfig config) throws ServletException;
  public abstract void service(ServletRequest req, ServletResponse res)
    throws ServletException, IOException;
}

Methods

destroy()

public abstract void destroy()

Description

Called when the server is preparing to unload a servlet. Used to clean up any outstanding resources (database connections, threads, file handles and so forth). The servlet programmer is responsible for making sure that any requests currently executing are allowed to finish.

getServletConfig()

public abstract ServletConfig getServletConfig()

Description

Returns the ServletConfig object passed to the init() method.

getServletInfo()

public abstract String getServletInfo()

Description

Returns a programmer-defined ...