Spring MVC Filter-Login Filter

The following code is the code that inherits the Onceperrequestfilter implementation login filtering:

/** * *  @author  geloin *  @date  2012-4-10  afternoon 2:37:38 */package  com.test.spring.filter;import java.io.IOException;import java.io.PrintWriter;import  javax.servlet.filterchain;import javax.servlet.servletexception;import  javax.servlet.http.httpservletrequest;import javax.servlet.http.httpservletresponse;import  org.springframework.web.filter.onceperrequestfilter;/** *  Login Filter  *  *  @author  geloin *  @date  2012-4-10  pm 2:37:38 */public class sessionfilter  extends onceperrequestfilter {/* *  (non-javadoc)  *  *  @see  *  org.springframework.web.filter.onceperrequestfilter#dofilterinternal ( *  javax.servlet.http.httpservletrequest, * javax.servlet.http.httpservletresponse,  Javax.servlet.FilterChain)  */@Overrideprotected  void dofilterinternal (httpservletrequest&Nbsp;request,httpservletresponse response, filterchain filterchain) throws ServletException , ioexception {//  non-filtered uristring[] notfilter = new string[] {  " Login.html ", " index.html " };//  requested Uristring uri = request.getrequesturi ();// Filter if  (uri.indexof ("background")  != -1)  {//  Filter Boolean if background is included in  uri  doFilter = true;for  (String s : notfilter)  {if  (Uri.indexof (s) &NBSP;!=&NBSP;-1)  {//  do not filter dofilter = false;break if the URI contains a URI that is not filtered;}} if  (doFilter)  {//  perform filtering//  get the login entity object obj = request.getsession () from the session. GetAttribute ("Logineduser");if  (null == obj)  {//  if the login entity does not exist in session, the popup prompts to log back in//   Set the character set of request and response to prevent garbled request.setcharacterencoding ("UTF-8"); Response.setcharacterencoding ("UTF-8"); Printwriter out = response.getwriteR (); string loginpage =  "..."; Stringbuilder builder = new stringbuilder (); Builder.append ("<script type=\" text/ Javascript\ ">") builder.append ("Alert (' page expires, please login again! ‘);"); Builder.append ("window.top.location.href="); Builder.append (LoginPage); Builder.append ("';"); Builder.append ("</script>"); Out.print (builder.tostring ());}  else {//  if the login entity exists in the session, continue to Filterchain.dofilter (Request, response);}}  else {//  continue Filterchain.dofilter (request, response) If filtering is not performed;}}  else {//  if the URI does not contain background, continue filterchain.dofilter (Request, response);}}

After you finish writing the filter, you need to configure it in Web. xml:

<filter><filter-name>sessionFilter</filter-name><filter-class> Com.test.spring.filter.sessionfilter</filter-class></filter><filter-mapping><filter-name >sessionFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping>

Spring MVC Filter-Login Filter