servlet HttpServletRequest request forwarding class 4

Request forwarding is, the server receives a request, from a resource to jump to another operation called resource request is forwarded.

 

 servlet 1:

// obtain parameters (work material) to view the request 
String username = req.getParameter ( "username" );
System.out.println ( "servlet1 view (counter 1) of the parameters (material):" + username);
 // to a material of the cover section, and transferred to servlet2 (2 counter) to see 
req.setAttribute ( "key1" "counter Chapter 1" );
 // ask: servlet2 (counter 2) how to go 
/ ** 
* forwards the request must begin with a slash, / slash indicates address: HTTP: // ip : Port / Engineering name / code mapped to the IDEA web directory
<br/>
//
*
*/
RequestDispatcher requestDispatcher = req.getRequestDispatcher("/servlet2");
//RequestDispatcher requestDispatcher = req.getRequestDispatcher("http://www.baidu.com");
// 走向 Sevlet2 (柜台 2 )
requestDispatcher.forward(req,resp);

 Forwarded to the doGet method of servlet2:

// obtain parameters (work material) to view the request 
String username = req.getParameter ( "username" );
System.out.println ( "view parameters (material) Servlet2 counter 2) (:" + username);
 // see if there is a counter seal 
Object req.getAttribute key1 = ( "key1" );
System.out.println ( "Are there Chapter 1 counter:" + key1);
 // handle their own business 
System.out.println ( "Servlet2 handle their own business");