ajax.html
<html>
<head>
<title> Ajax at work </title>
<script language = "javascript">
var XMLHttpRequestObject = false;
if (window.XMLHttpRequest)
{
XMLHttpRequestObject = new XMLHttpRequest();
}
else if (window.ActiveXObject)
{
XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
}
function getData(dataSource, divID)
{
if(XMLHttpRequestObject)
{
var obj = document.getElementById(divID);
XMLHttpRequestObject.open("GET", dataSource);
XMLHttpRequestObject.onreadystatechange = function()
{
if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200)
{
obj.innerHTML = XMLHttpRequestObject.responseText;
}
}
XMLHttpRequestObject.send(null);
}
}
</script>
</head>
<body>
<h1> Fetching data with Ajax </h1>
<FORM ACTION="ShowParameters"
METHOD="POST">
Item Number:
<INPUT TYPE="TEXT" NAME="itemNum"><BR>
Quantity:
<INPUT TYPE="TEXT" NAME="quantity"><BR>
Price Each:
<INPUT TYPE="TEXT" NAME="price" VALUE="$"><BR>
<HR>
First Name:
<INPUT TYPE="TEXT" NAME="firstName"><BR>
Last Name:
<INPUT TYPE="TEXT" NAME="lastName"><BR>
Middle Initial:
<INPUT TYPE="TEXT" NAME="initial"><BR>
Shipping Address:
<TEXTAREA NAME="address" ROWS=3 COLS=40></TEXTAREA><BR>
Credit Card:<BR>
<INPUT TYPE="RADIO" NAME="cardType"
VALUE="Visa">Visa<BR>
<INPUT TYPE="RADIO" NAME="cardType"
VALUE="Master Card">Master Card<BR>
<INPUT TYPE="RADIO" NAME="cardType"
VALUE="Amex">American Express<BR>
<INPUT TYPE="RADIO" NAME="cardType"
VALUE="Discover">Discover<BR>
<INPUT TYPE="RADIO" NAME="cardType"
VALUE="Java SmartCard">Java SmartCard<BR>
Credit Card Number:
<INPUT TYPE="PASSWORD" NAME="cardNum"><BR>
Repeat Credit Card Number:
<INPUT TYPE="PASSWORD" NAME="cardNum"><BR><BR>
<CENTER>
<INPUT TYPE="SUBMIT" VALUE="Submit Order">
</CENTER>
<input type = "button" value = "Display Message"
onclick = "getData('ShowParameters.java', 'targetDiv')">
</FORM>
<div id="targetDiv">
<p>The fetched data will go here.</p>
</div>
</body>
</html>ShowParameters.java
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
public class ShowParameters extends HttpServlet {
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println( "<BODY>\n" +
"<TABLE BORDER=1 ALIGN=CENTER>\n" +
"<TR>\n" +
"<TH>Parameter Name<TH>Parameter Value(s)");
Enumeration paramNames = request.getParameterNames();
while(paramNames.hasMoreElements()) {
String paramName = (String)paramNames.nextElement();
out.println("<TR><TD>" + paramName + "\n<TD>");
String[] paramValues = request.getParameterValues(paramName);
if (paramValues.length == 1) {
String paramValue = paramValues[0];
if (paramValue.length() == 0)
out.print("<I>No Value</I>");
else
out.print(paramValue);
} else {
out.println("<UL>");
for(int i=0; i<paramValues.length; i++) {
out.println("<LI>" + paramValues[i]);
}
out.println("</UL>");
}
}
out.println("</TABLE>\n</BODY></HTML>");
}
public void doPost(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}