JSP XMLHttpRequest Dynamic Non-refreshing and its Chinese garbled processing _jsp programming

1. Join in the <script type= "Text/javascript" in the page
XMLHTTP request with no refresh request
var Http_request=false;
function createrequest (URL)
{
Http_request = false;
if (window. XMLHttpRequest) {//Mozilla, Safari,...
Http_request = new XMLHttpRequest ();
if (Http_request.overridemimetype) {
Http_request.overridemimetype (' text/html ');
}
else if (window. ActiveXObject) {//IE
try {
Http_request = new ActiveXObject ("Msxml2.xmlhttp");
catch (e) {
try {
Http_request = new ActiveXObject ("Microsoft.XMLHTTP");
catch (e) {}
}
}
if (!http_request) {
Alert (' Cannot create XMLHTTP instance! ');
return false;
}
http_request.onreadystatechange=alertcontents;
Http_request.open ("POST", url,true);
Http_request.send (NULL);
}
2. Call--in the JS call request "Control is the url-mapping of the servlet configuration, the reference is the same as the generic URL"
Createrequest (' control ' + '? Cmd=listen ');
3. Handle "Chinese garbled problem" in servlet
PrintWriter out;
Response.setcontenttype ("Html/text");//This 5 line must be used for outputting Chinese, otherwise garbled
Response.setcharacterencoding ("UTF-8");
Response.setheader ("Cache-control", "No-cache");
Out=response.getwriter ();
Out.println ("Sorry, the system is busy, please try again later!") "); For the returned response result, the page is displayed directly with alert ()