Hello Service

A simple service program


 A simple service program to show usage of Service type of applications.

This demo program listens on a PORT, accepts connections and serves like a HTTP server. It responses a simple message on any request.

1. Edit a java source file: "X:\demos\src\hello\HelloService.java"

package hello;

import java.io.*;
import java.net.*;

public class HelloService {

    // port to listen
    public static int PORT = 8080;

    public static void main(String[] args) throws IOException {
        // load port settings from properties
        PORT = Integer.parseInt(System.getProperty("hello.service.port",
        // listen
        ServerSocket listener = new ServerSocket(PORT);
        System.out.println("HelloService started.");
        // accept a connection
        Socket socket;
        while(null != (socket = listener.accept())) {
            // open a thead to serve
            final Socket fsocket = socket;
            Thread t = new Thread(new Runnable() {
                // A simple variable to let response changing
                int n = 1;
                public void run() {
                    try {
                        BufferedReader in = new BufferedReader(new InputStreamReader(
                                fsocket.getInputStream(), "iso-8859-1"));
                        PrintStream out = new PrintStream(
                                new BufferedOutputStream(fsocket.getOutputStream()));
                        // Get any http request
                        while(readHttpRequest(in)) {
                            // Response a simple message
                            String msg = "<font color='red'>Hello, this is a demo service," +
                                    " you have requested " + n++ + " times.";
                            out.println("HTTP/1.1 200 OK");
                            out.println("Content-Type: text/html; charset=iso-8859-1");
                            out.println("Content-Length: " + msg.length());
                    catch (IOException e) {
                    finally {
                        try { fsocket.close(); } catch (IOException e) { }

                // Get any http request
                private boolean readHttpRequest(BufferedReader in) {
                    try {
                        String line;
                        while((line = in.readLine()) != null)
                            if(line.length() == 0) {
                                return true;
                    catch (IOException e) {
                    return false;


2. Enter "X:\demos" directory and compile it to a class file:

X:\>cd demos
X:\demos>javac src/hello/HelloService.java

3. Make a jar file:

X:\demos>jar -cvf helloservice.jar -C src .

4. Use Jar2Exe to generate exe file for Windows and Linux separately:

X:\demos>j2ewiz helloservice.jar /m hello.HelloService /type service /service HelloService
X:\demos>j2ewiz helloservice.jar /m hello.HelloService /type service /platform linux

5. Install the program as a Service on Windows and Linux respectively:

helloservice /install

6. Start the service by 'net' command on Windows, by 'service' command on Linux:

net start HelloService

Now open a browser to visit http://localhost:8080 to test the service.

7. Download the program for reference.

See Also

  • See Run as Service page for more details about Service type of applications.