How do I get parameter names from servlet request?

This example show you how to obtain parameter name from servlet request. By calling request.getParameterNames() you will get an Enumeration object by iterating this object you can get the parameter names.

package org.kodejava.example.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class ParameterName extends javax.servlet.http.HttpServlet implements
		javax.servlet.Servlet {

	public ParameterName() {
		super();
	}

	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		
		PrintWriter pw = response.getWriter();

                //
                // Let's obtains parameters name here! 
                //
		Enumeration enumeration = request.getParameterNames();
		while (enumeration.hasMoreElements()) {
			String parameterName = (String) enumeration.nextElement();
			pw.println("Parameter = " + parameterName);
		}
		pw.close();
	}

	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
	}
}

When you call the servlet and pass some parameters you get the parameter name echoed on the web browser.

http://localhost:8080/java-web-examples/ParameterName?txid=001&item=10&price=1000

Parameter = price
Parameter = item
Parameter = txid

Wayan Saryada

A programmer, a slow runner, a recreational open water diver, currently living in the island of Bali, Indonesia. Mostly programming in Java, creating web based application with Spring Framework, JPA, etc. If you need help on Java programming you can hire me on Fiverr.

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