Executing executable Jar file from Java Program

Sample code to execute jar file from Java Program.

Pre-requisite
1. Need to have executable jar file.
2. Copy the code in your workspace and Run the code.

 package com.test.reusable.enterprise.service;  
 import java.io.BufferedReader;  
 import java.io.File;  
 import java.io.IOException;  
 import java.io.InputStream;  
 import java.io.InputStreamReader;  
 import org.apache.commons.lang.exception.ExceptionUtils;  
 public class ExecuteJarFile {  
      public static void main(String[] args) {  
           try {  
                //Method1 to Execute Jar file From Java Program  
                     ProcessBuilder pb = new ProcessBuilder("java", "-jar", "HelloWorld.jar"); // command to execute jar file with fileName.jar  
                  pb.redirectErrorStream(true);  
                  pb.directory(new File("C:/www/")); // Directory path where your jar file is placed.   
                  Process p = pb.start();  
                  InputStream is = p.getInputStream();  
                  BufferedReader br = new BufferedReader(new InputStreamReader(is));  
                  System.out.println("===== Method 1 output =====");  
                  for (String line = br.readLine(); line != null; line = br.readLine()) {  
                      System.out.println( line ); // Or just ignore it  
                  }  
                  p.waitFor();       
                //Method2 to Execute Jar file From Java Program  
                  Runtime re = Runtime.getRuntime();  
                  BufferedReader output = null;             
                  try{   
                   Process cmd = re.exec("java -jar C:/www/HelloWorld.jar"); // command to execute jar file with complete path  
                   output = new BufferedReader(new InputStreamReader(cmd.getInputStream()));  
                  } catch (IOException ioe){  
                   ioe.printStackTrace();  
                  }  
                  String resultOutput = output.readLine();  
                  System.out.println("===== Method 2 output =====");  
                  System.out.println("resultOutput :: "+resultOutput);  
           } catch (Exception e2) {  
                String fullStackTrace = ExceptionUtils.getFullStackTrace(e2);  
                System.out.println("Caught Exception :: "+fullStackTrace);  
           }  
      }  
 }  

=========== Output ===========

I hope that above given example gives you a better understanding of executing jar file from java program.