setInitParameter() Method Example

In this tutorial you will learn how can you set a context initialization parameter in Servlet 3

setInitParameter() Method Example

In this tutorial you will learn how can you set a context initialization parameter in Servlet 3

setInitParameter() method of ServletContext is used to set the context initialization parameter by the specified name and value. Return type of this method is a boolean type which returns 'true' on successfully set the value otherwise returns false, if the value you are trying to set is already exists.

Syntax :

boolean setInitParameter(String name, String value);

Here parameter 'name' is a specified name by which you want to set the context initialization parameter and the parameter 'value' is a specified value that you want to bind with the corresponding specified name.

Example :

Here I am giving a simple example which will demonstrate you how to set the context initialization parameter using setInitParameter() method.

SetInitParameterExample.java

package roseindia.webContext;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(urlPatterns="/SetInitParameterExample",
initParams={
@WebInitParam(name="middleName", value="Kumar")
}
)
public class SetInitParameterExample extends HttpServlet
{
private static final long serialVersionUID = 1L;

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
ServletConfig config= getServletConfig();

ServletContext context= getServletContext();
context.setInitParameter("firstName", "Bipul");

response.setContentType("text/html");
PrintWriter out= response.getWriter();

String contextParam= context.getInitParameter("firstName");
out.println("Context Parameter Value = "+contextParam);

String configParam= config.getInitParameter("middleName");
out.println("<br>Config Parameter Value = "+configParam);

context.setInitParameter("lastName", "Choudhary");
String contextParam1= context.getInitParameter("lastName");

out.println("<br>Context Parameter Value = "+contextParam1);
boolean bol= context.setInitParameter("lastName", "Kumar");

if(bol!=true)
{
out.println("<br>you can not replace the value with same key");
}
else
{
out.println("Value is replaced.");
out.println("And Replaced value is : "+context.getInitParameter("lastName"));
} 
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
doGet(request, response);
}
}

Output :

When you will execute the above example you will get the output as :

Download Source Code