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java.lang.Objectjavax.servlet.GenericServlet
Defines a generic, protocol-independent
 servlet. To write an HTTP servlet for use on the
 Web, extend 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 Summary | |
| GenericServlet()Does nothing. | |
| Method Summary | |
|  void | destroy()Called by the servlet container to indicate to a servlet that the servlet is being taken out of service. | 
|  java.lang.String | getInitParameter(java.lang.String name)Returns a Stringcontaining the value of the named
 initialization parameter, ornullif the parameter does
 not exist. | 
|  java.util.Enumeration | getInitParameterNames()Returns the names of the servlet's initialization parameters as an EnumerationofStringobjects,
 or an emptyEnumerationif the servlet has no
 initialization parameters. | 
|  ServletConfig | getServletConfig()Returns this servlet's ServletConfigobject. | 
|  ServletContext | getServletContext()Returns a reference to the ServletContextin which this servlet
 is running. | 
|  java.lang.String | getServletInfo()Returns information about the servlet, such as author, version, and copyright. | 
|  java.lang.String | getServletName()Returns the name of this servlet instance. | 
|  void | init()A convenience method which can be overridden so that there's no need to call super.init(config). | 
|  void | init(ServletConfig config)Called by the servlet container to indicate to a servlet that the servlet is being placed into service. | 
|  void | log(java.lang.String msg)Writes the specified message to a servlet log file, prepended by the servlet's name. | 
|  void | log(java.lang.String message,
    java.lang.Throwable t)Writes an explanatory message and a stack trace for a given Throwableexception
 to the servlet log file, prepended by the servlet's name. | 
| abstract  void | service(ServletRequest req,
        ServletResponse res)Called by the servlet container to allow the servlet to respond to a request. | 
| Methods inherited from class java.lang.Object | 
| clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait | 
| Constructor Detail | 
public GenericServlet()
init methods.
| Method Detail | 
public void destroy()
Servlet.destroy().
destroy in interface Servletpublic java.lang.String getInitParameter(java.lang.String name)
String containing the value of the named
 initialization parameter, or null if the parameter does
 not exist.  See ServletConfig.getInitParameter(java.lang.String).
 This method is supplied for convenience. It gets the 
 value of the named parameter from the servlet's 
 ServletConfig object.
getInitParameter in interface ServletConfigname - a String specifying the name 
				of the initialization parameter
String containing the value
				of the initialization parameterpublic java.util.Enumeration getInitParameterNames()
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.
getInitParameterNames in interface ServletConfigString
				objects containing the names of 
				the servlet's initialization parameterspublic ServletConfig getServletConfig()
ServletConfig object.
getServletConfig in interface ServletServletConfig object
				that initialized this servletServlet.init(javax.servlet.ServletConfig)public ServletContext getServletContext()
ServletContext in which this servlet
 is running.  See ServletConfig.getServletContext().
 This method is supplied for convenience. It gets the 
 context from the servlet's ServletConfig object.
getServletContext in interface ServletConfigServletContext object
				passed to this servlet by the init
				methodServletContextpublic java.lang.String getServletInfo()
Servlet.getServletInfo().
getServletInfo in interface Servlet
public void init(ServletConfig config)
          throws ServletException
Servlet.init(javax.servlet.ServletConfig).
 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).
init in interface Servletconfig - the ServletConfig object
					that contains configutation
					information for this servlet
ServletException - if an exception occurs that
					interrupts the servlet's normal
					operationUnavailableException
public void init()
          throws ServletException
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().
ServletException - if an exception occurs that
					interrupts the servlet's
					normal operationpublic void log(java.lang.String msg)
ServletContext.log(String).
msg - a String specifying
			the message to be written to the log file
public void log(java.lang.String message,
                java.lang.Throwable t)
Throwable exception
 to the servlet log file, prepended by the servlet's name.
 See ServletContext.log(String, Throwable).
message - a String that describes
				the error or exceptiont - the java.lang.Throwable error
 				or exception
public abstract void service(ServletRequest req,
                             ServletResponse res)
                      throws ServletException,
                             java.io.IOException
Servlet.service(javax.servlet.ServletRequest, javax.servlet.ServletResponse).
 
 This method is declared abstract so subclasses, such as 
 HttpServlet, must override it.
service in interface Servletreq - the ServletRequest object
			that contains the client's requestres - the ServletResponse object
			that will contain the servlet's response
ServletException - if an exception occurs that
					interferes with the servlet's
					normal operation occurred
java.io.IOException - if an input or output
					exception occurspublic java.lang.String getServletName()
ServletConfig.getServletName().
getServletName in interface ServletConfig| 
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