An example of basic Ajax application

JS:

<SCRIPT> var xhr = ajaxxmlhttprequest (); function getsups () {If (xhr = NULL) {alert ('ajax not supported by browsers '); return;} xhr. onreadystatechange = statechanged; var url = "supliers. do? Method = getallsup "; xhr. open ("Post", URL, true); xhr. setRequestHeader ("Content-Type", "application/X-WWW-form-urlencoded");} function statechanged () {// alert ("test"); If (xhr. readystate = 4) {document. getelementbyid ("Sup "). innerhtml = xhr. responsetext; return ;}} function ajaxxmlhttprequest () {var XMLHTTP; try {// Firefox, opera 8.0 +, Safari XMLHTTP = new XMLHttpRequest ();} catch (E) {// Internet Explorer try {XM Lhttp = new activexobject ("msxml2.xmlhttp");} catch (e) {try {XMLHTTP = new activexobject ("Microsoft. XMLHTTP ");} catch (e) {alert (" your browser does not support Ajax! "); Return false ;}}return XMLHTTP ;}</SCRIPT>

Java code

 

 public ActionForward getSups(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {  List<Supplier> rlist = this.supServices.getAllSupp();  String beg1 = "<option value= ";  String beg2=">";  String end = "</option>";  for(Supplier sup:rlist){   beg1+=sup.getS_id();   beg1+=beg2;   beg1+=sup.getSupplier_name();   beg1+=end;  }  PrintWriter pw = response.getWriter();  pw.write(beg1);  return null; }