Servlet Controller Dispatcher : RequestDispatcher « Servlet « Java Tutorial

Java Tutorial 1.  Language 2.  Data Type 3.  Operators 4.  Statement Control 5.  Class Definition 6.  Development 7.  Reflection 8.  Regular Expressions 9.  Collections 10.  Thread 11.  File 12.  Generics 13.  I18N 14.  Swing 15.  Swing Event 16.  2D Graphics 17.  SWT 18.  SWT 2D Graphics 19.  Network 20.  Database 21.  Hibernate 22.  JPA 23.  JSP 24.  JSTL 25.  Servlet 26.  Web Services SOA 27.  EJB3 28.  Spring 29.  PDF 30.  Email 31.  J2ME 32.  J2EE Application 33.  XML 34.  Design Pattern 35.  Log 36.  Security 37.  Apache Common 38.  Ant 39.  JUnit Java Java Source Code / Java Documentation Java Open Source Jar File Download Java Articles Java Products Java by API Photoshop Tutorials Maya Tutorials Flash Tutorials 3ds-Max Tutorials Illustrator Tutorials GIMP Tutorials C# / C Sharp C# / CSharp Tutorial C# / CSharp Open Source ASP.Net ASP.NET Tutorial JavaScript DHTML JavaScript Tutorial JavaScript Reference HTML / CSS HTML CSS Reference C / ANSI-C C Tutorial C++ C++ Tutorial Ruby PHP Python Python Tutorial Python Open Source SQL Server / T-SQL SQL Server / T-SQL Tutorial Oracle PL / SQL Oracle PL/SQL Tutorial PostgreSQL SQL / MySQL MySQL Tutorial VB.Net VB.Net Tutorial Flash / Flex / ActionScript VBA / Excel / Access / Word XML XML Tutorial Microsoft Office PowerPoint 2007 Tutorial Microsoft Office Excel 2007 Tutorial Microsoft Office Word 2007 Tutorial

Java Tutorial » Servlet » RequestDispatcher   25. 14. 2. Servlet Controller Dispatcher import java.io.*; import javax.servlet.*; import javax.servlet.http.*; import java.util.*; public class MyServlet extends HttpServlet {     public void doGet(HttpServletRequest request,          HttpServletResponse response)           throws ServletException, java.io.IOException {         RequestDispatcher dispatcher = null;         String param = request.getParameter("go");              if (param == null)                  throw new                       ServletException("Missing parameter in Controller.");              else if (param.equals("weather"))                  dispatcher = getServletContext().                      getNamedDispatcher("Weather");              else if (param.equals("maps"))                  dispatcher = getServletContext().                      getNamedDispatcher("Maps");             else                 throw new ServletException(                     "Improper parameter passed to Controller.");          /*check for a null dispatcher, then              dispatch the request to the correct URL*/         if (dispatcher != null)             dispatcher.forward(request,response);         else             throw new ServletException(               "Controller received a null dispatcher.");     } } <?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE web-app     PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN"     "http://java.sun.com/j2ee/dtds/web-app_2_2.dtd"> <web-app>     <servlet><servlet-name>MyServletName</servlet-name>              <servlet-class>MyServlet</servlet-class>         <init-param>             <param-name>                 go             </param-name>             <param-value>                 weather             </param-value>         </init-param>                   </servlet>          <servlet-mapping><servlet-name>MyServletName</servlet-name>         <url-pattern>/index.html</url-pattern>     </servlet-mapping> </web-app>   Download:  ServletControllerDispatcher.zip( 89 k) 25. 14. RequestDispatcher 25. 14. 1.  Servlet Forwarding Dispatch 25. 14. 2.  Servlet Controller Dispatcher