Accessing post variables using Java Servlets
JavaHttpServletsJava Problem Overview
What is the Java equivalent of PHP's $_POST? After searching the web for an hour, I'm still nowhere closer.
Java Solutions
Solution 1 - Java
Here's a simple example. I didn't get fancy with the html or the servlet, but you should get the idea.
I hope this helps you out.
<html>
<body>
<form method="post" action="/myServlet">
<input type="text" name="username" />
<input type="password" name="password" />
<input type="submit" />
</form>
</body>
</html>
Now for the Servlet
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class MyServlet extends HttpServlet {
public void doPost(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
String userName = request.getParameter("username");
String password = request.getParameter("password");
....
....
}
}
Solution 2 - Java
Your HttpServletRequest object has a getParameter(String paramName) method that can be used to get parameter values. <http://java.sun.com/javaee/5/docs/api/javax/servlet/ServletRequest.html#getParameter(java.lang.String)>
Solution 3 - Java
POST variables should be accessible via the request object: HttpRequest.getParameterMap(). The exception is if the form is sending multipart MIME data (the FORM has enctype="multipart/form-data"). In that case, you need to parse the byte stream with a MIME parser. You can write your own or use an existing one like the Apache Commons File Upload API.
Solution 4 - Java
The previous answers are correct but remember to use the name attribute in the input fields (html form) or you won't get anything. Example:
<input type="text" id="username" /> <!-- won't work --> <input type="text" name="username" /> <!-- will work --> <input type="text" name="username" id="username" /> <!-- will work too -->
All this code is HTML valid, but using getParameter(java.lang.String) you will need the name attribute been set in all parameters you want to receive.
Solution 5 - Java
For getting all post parameters there is Map which contains request param name as key and param value as key.
Map params = servReq.getParameterMap();
And to get parameters with known name normal
String userId=servReq.getParameter("user_id");