Get Remote Host from Servlet Request : Request « Servlet « Java Tutorial

1. Java Tutorial
2. Servlet
3. Request

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class MyServlet extends HttpServlet {

  public void doGet(HttpServletRequest req, HttpServletResponse res)
                               throws ServletException, IOException {
    res.setContentType("text/html");
    PrintWriter out = res.getWriter();

    // Get the client's hostname
    String remoteHost = req.getRemoteHost();

    out.println("remoteHost:"+remoteHost);
    // See if the client is allowed
    if (! isHostAllowed(remoteHost)) {
      out.println("Access <BLINK>denied</BLINK>");
    }
    else {
      out.println("Access granted");
      // Display download links, etc...
    }
  }

  // Disallow hosts ending with .cu, .ir, .iq, .kp, .ly, .sy, and .sd.
  private boolean isHostAllowed(String host) {
    return (!host.endsWith(".cu") &&
            !host.endsWith(".ir") &&
            !host.endsWith(".iq") &&
            !host.endsWith(".kp") &&
            !host.endsWith(".ly") &&
            !host.endsWith(".sy") &&
            !host.endsWith(".sd"));
  }
}

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN"
    "http://java.sun.com/j2ee/dtds/web-app_2_2.dtd">

<web-app>
    <servlet><servlet-name>MyServletName</servlet-name>
             <servlet-class>MyServlet</servlet-class>
    </servlet>
    
    <servlet-mapping><servlet-name>MyServletName</servlet-name>
        <url-pattern>/index.html</url-pattern>
    </servlet-mapping>
</web-app>

25.12.Request
	25.12.1.	Print Request Headers for a Servlet
	25.12.2.	Get Servlet Request Parameter
	25.12.3.	Get Remote User and display welcome message
	25.12.4.	Get Users IP Address
	25.12.5.	Get Remote Host from Servlet Request
	25.12.6.	Request parsing and encoding utility methods