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Home » apache-tomcat-6.0.26-src » javax » servlet » [javadoc | source]
javax.servlet
abstract public class: GenericServlet [javadoc | source]
java.lang.Object
   javax.servlet.GenericServlet

All Implemented Interfaces:
    ServletConfig, Servlet, Serializable

Direct Known Subclasses:
    HttpServlet

Defines a generic, protocol-independent servlet. To write an HTTP servlet for use on the Web, extend javax.servlet.http.HttpServlet instead.

GenericServlet implements the Servlet and ServletConfig interfaces. GenericServlet may be directly extended by a servlet, although it's more common to extend a protocol-specific subclass such as HttpServlet.

GenericServlet makes writing servlets easier. It provides simple versions of the lifecycle methods init and destroy and of the methods in the ServletConfig interface. GenericServlet also implements the log method, declared in the ServletContext interface.

To write a generic servlet, you need only override the abstract service method.

Constructor:
 public GenericServlet() 
Method from javax.servlet.GenericServlet Summary:
destroy,   getInitParameter,   getInitParameterNames,   getServletConfig,   getServletContext,   getServletInfo,   getServletName,   init,   init,   log,   log,   service
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.servlet.GenericServlet Detail:
 public  void destroy() 
    Called by the servlet container to indicate to a servlet that the servlet is being taken out of service. See Servlet#destroy .
 public String getInitParameter(String name) 
    Returns a String containing the value of the named initialization parameter, or null if the parameter does not exist. See ServletConfig#getInitParameter .

    This method is supplied for convenience. It gets the value of the named parameter from the servlet's ServletConfig object.

 public Enumeration getInitParameterNames() 
    Returns the names of the servlet's initialization parameters as an Enumeration of String objects, or an empty Enumeration if the servlet has no initialization parameters. See ServletConfig#getInitParameterNames .

    This method is supplied for convenience. It gets the parameter names from the servlet's ServletConfig object.

 public ServletConfig getServletConfig() 
 public ServletContext getServletContext() 
 public String getServletInfo() 
    Returns information about the servlet, such as author, version, and copyright. By default, this method returns an empty string. Override this method to have it return a meaningful value. See Servlet#getServletInfo .
 public String getServletName() 
 public  void init() throws ServletException 
    A convenience method which can be overridden so that there's no need to call super.init(config).

    Instead of overriding #init(ServletConfig) , simply override this method and it will be called by GenericServlet.init(ServletConfig config). The ServletConfig object can still be retrieved via #getServletConfig .

 public  void init(ServletConfig config) throws ServletException 
    Called by the servlet container to indicate to a servlet that the servlet is being placed into service. See Servlet#init .

    This implementation stores the ServletConfig object it receives from the servlet container for later use. When overriding this form of the method, call super.init(config).

 public  void log(String msg) 
 public  void log(String message,
    Throwable t) 
 abstract public  void service(ServletRequest req,
    ServletResponse res) throws ServletException, IOException
    Called by the servlet container to allow the servlet to respond to a request. See Servlet#service .

    This method is declared abstract so subclasses, such as HttpServlet, must override it.