页面代码：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>HelloServlet.html</title>
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="this is my page">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<!--<link rel="stylesheet" type="text/css" href="./styles.css">-->
<script type="text/javascript">
var outMsg = "";
var xhr;
function createXMLHttpRequest(){
if(window.ActiveXObject){
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}else if(window.XMLHttpRequest){
xhr = new XMLHttpRequest();
}
}
function createQueryString(){
var userName = document.getElementById("username").value;
var queryString = "userName="+userName;
return queryString;
}
function doRequest(){
createXMLHttpRequest();
var queryString = "HelloAjaxJava1?";
queryString = queryString + createQueryString();
xhr.onreadystatechange = handleStatechange;
xhr.open("POST",queryString,true);
xhr.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
xhr.send(null);
}
function handleStatechange(){
if(xhr.readyState == 4){
if(xhr.status == 200){
parseResults();
}
}
}
function parseResults(){
responseDiv = document.getElementById("serverResponse");
if(responseDiv.hasChildNodes()){
responseDiv.removeChild(responseDiv.childNodes[0]);
}
var responseText = document.createTextNode(xhr.responseText);
responseDiv.appendChild(responseText);
}
</script>
</head>
<body>
<form action = "#">
password:
<input type = "password" id = "username"/>
<input type = "reset" value = "reset"/>
<input type = "button" id = "submission" value = "submit" onclick="doRequest();"/>
</form>
<h2>server response</h2>
<div id = "serverResponse"></div>
</body>
</html>
Servlet代码：
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class HelloAjaxJava1 extends HttpServlet {
/**
* Constructor of the object.
*/
public HelloAjaxJava1() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out
.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the GET method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();
String userName = request.getParameter("userName");
String userText = "密码是 : "+userName;
out.println(userText);
out.flush();
out.close();
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
