Forwards. Hides the Jsp.url address. MD

First, forwarding parameters:

1. Transfer the parameters inside the JSP via Loginservlet to Pageselvert:

@WebServlet("/login") Public  class loginservlet extends httpservlet { protected void dopost(httpservletrequest request,httpservletresponse response)  throws servletexception,ioexception{//forward to PageservletRequest.getrequestdispatcher ("/page"), ForWord (REQUEST,REAPOMSE); }}@WebServlet("page") Public  class pageservlet extends httpservlet { protected void dopost(httpservletrequest request,httpservletresponse response)  throws servletexception,ioexception{String usename = Request.getparameter ("Usename"); String Password = request.getparameter ("password"); System.out.pritln (Usename); System.out.pritln (PASSWORRD);}}

2. Bring the values stored in the Loginservlet to the Pageservlet:

@WebServlet("/login") Public class loginservlet extends httpservlet {Protected void dopost(httpservletrequest request,httpservletresponse response) {//In the Request object, set the property value, as long as it is the same request object to obtain this data (so forward can, redirect No, redirect is two) //Send e-mail to the past (only in front, if it is after the Getrequestdispatcher (behind), you will not get it)Request.setattribute ("Email", "123456@163. com "); Request.getrequestdispatcher ("/page"), ForWord (Request,response);}}@WebServlet("/page") Public class pageservlet extends httpservlet {Protected void dopost(httpservletrequest request,httpservletresponse response) {//Get [email protected]string email = (string) request.getattribute ("email");//Delete email valuesRequest.removeattribute ("email");//Get all the namesRequest.getattributenames (); String usename = Request.getparameter ("Usename"); String Password = request.getparameter ("password");}}

* * Forwarding Parameters: * * removeattribute Delete getattributenames get all the names SetAttribute set value getattribute get value

The request response their life cycle, which ends between requests and responses.

Second, hidden JSP:

You can put the JSP into the Web-inf directory, and later can only use forwarding to access the following JSP

<welcome-file-list><----><welcome-file >index.jsp</welcome-file></welcome-file-list>

Purpose: Hide the JSP to change the access page to the following:

<welcome-file-list><welcome-file>/web-inf/pages/index.jsp</ welcome-file></welcome-file-list>

Front add "/" directly to the place where it is the root directory

//admin for a virtual clip @WebServlet("/admin/test") Public  class testservlet entends httpservlet { protected void deget(httpservletquest req,httpservletresponse resp) throws Servletexception,ioeception{Resp.sendredirect ("index.jsp");}}

There are 3 ways to access it:

//"..." Represents jumping up a directory in the index.jsp directory resp.sendredirect (".. /index.jsp ");

System.out.println (Req.getcontextpath ()); //servlet7_url Resp.sendredirect (Req.getcontextpath () +"/index.jsp");

"/");

Third, garbled problem:

TOMCAT7 version conversion garbled need to see the method to go to get the String class transcoding post directly set the code can be

String s=req.getparament ("text");        ↓

<fromactoin="lm"method="Get">

System.out.println (new String (s.getbytes (iso-8859),"Utf-8")), req, Setcharacterencoding ("UTF-8"); String s=req.getparamenter ("test");        ↓

<fromactoin="lm"method="POST">

System.out.println (s);

TOMCAT8 version does not require a half-paragraph method, directly set the transcoding can be

Req.setcharacterencoding ("UTF-8"); String s=req.getparameter ("test"); System.out.println (s);

If you do not transcode, direct printing, there will be garbled, such as:

If you want to nginx the word inside a servlet into another servlet, you need to transcode it, such as:

Request.sendredirect (text1?name= "dog Son");

This should be written as:

 Text0Servlet:Request.sendRedirect ("Text1?name=" +urlencode.encode ("dog Son")); Text1servlet: //tomcat8  Request.setcharacterencoding ("Utf-8 "); //tomcat 7  String S=new  String (request.getparameter ("name"). GetBytes ("Iso-8859 - 1  ")," Utf-8  "); System.out.println (Request.getparameter ("name")); 

Resp.sendredirect ("test1?name=" +urlencoder.encode ("polymorphic","UTF-8"));                           ↓req.setcharacterencoding ("UTF-8"//string s=new String (req.getparameter ("name"). GetBytes (" Iso-8859-1 ")," UTF-8 ") System.out.println (Req.getparameter);

Forwards. Hides the Jsp.url address. MD