Question

I have a jar file that runs this code:

public class InputOutput {      /**      * @param args      * @throws IOException       */     public static void main(String[] args) throws IOException {         boolean cont = true;         BufferedReader in = new BufferedReader(new InputStreamReader(System.in));         while (cont) {             System.out.print('Input something: ');             String temp = in.readLine();             if (temp.equals('end')) {                 cont = false;                 System.out.println('Terminated.');             }             else                 System.out.println(temp);         }     } } 

I want to program another java class that executes this jar file and can get the input and send output to it. Is it possible? The current code I have is this but it is not working:

public class JarTest {      /**      * Test input and output of jar files      * @author Jack      */     public static void main(String[] args) {         try {             Process io = Runtime.getRuntime().exec('java -jar InputOutput.jar');             BufferedReader in = new BufferedReader(new InputStreamReader(io.getInputStream()));             OutputStreamWriter out = new OutputStreamWriter(io.getOutputStream());             boolean cont = true;             BufferedReader consolein = new BufferedReader(new InputStreamReader(System.in));             while (cont) {                 String temp = consolein.readLine();                 out.write(temp);                 System.out.println(in.readLine());             }         } catch (IOException e) {             e.printStackTrace();         }      } } 

Thanks for your help

Answer 1

Using Runtime.exec is platform dependent.

If you’re using windows try prepending:

cmd /c 

to

java -jar .... etc. et 

Something like:

...getRuntime().exec('cmd /c java -jar InputOutput....  

See this also: Make system call and return stdout output.