Executing another application from Java

The Runtime.getRuntime().exec() approach is quite troublesome, as you'll find out shortly.

Take a look at the Apache Commons Exec project. It abstracts you way of a lot of the common problems associated with using the Runtime.getRuntime().exec() and ProcessBuilder API.

It's as simple as:

String line = "myCommand.exe";
CommandLine commandLine = CommandLine.parse(line);
DefaultExecutor executor = new DefaultExecutor();
executor.setExitValue(1);
int exitValue = executor.execute(commandLine);

Yes it is possible using ProcessBuilder.

ProcessBuilder example:

import java.io.*;
import java.util.*;

public class CmdProcessBuilder {
  public static void main(String args[]) 
     throws InterruptedException,IOException 
  {
    List<String> command = new ArrayList<String>();
    command.add(args[0]);


    ProcessBuilder builder = new ProcessBuilder(command);
    Map<String, String> environ = builder.environment();

    final Process process = builder.start();
    InputStream is = process.getInputStream();
    InputStreamReader isr = new InputStreamReader(is);
    BufferedReader br = new BufferedReader(isr);
    String line;
    while ((line = br.readLine()) != null) {
      System.out.println(line);
    }
    System.out.println("Program terminated!");
  }
}

Check these examples:

http://www.rgagnon.com/javadetails/java-0014.html

http://www.java-tips.org/java-se-tips/java.util/from-runtime.exec-to-processbuilder.html

Here is an example of how to use ProcessBuilder to execute your remote application. Since you do not care about input/output and/or errors, you can do as follows:

List<String> args = new ArrayList<String>();
args.add ("script.bat"); // command name
args.add ("-option"); // optional args added as separate list items
ProcessBuilder pb = new ProcessBuilder (args);
Process p = pb.start();
p.waitFor();

the waitFor() method will wait until the process had ended before continuing. This method returns the error code of the process but, since you don't care about it, I didn't put it in the example.

I assume that you know how to execute the command using the ProcessBuilder.

Executing a command from Java always should read the stdout and stderr streams from the process. Otherwise it can happen that the buffer is full and the process cannot continue because writing its stdout or stderr blocks.

You can execute a batch instruction, or any other application using

Runtime.getRuntime().exec(cmd);

cmd is the command or te application path.

Also yo can wait for executing and getting the return code (to check if its executed correctly) with this code:

  Process p = Runtime.getRuntime().exec(cmd);
  p.waitFor();
  int exitVal = p.exitValue();

You have a full explanation of different types of calls here http://www.rgagnon.com/javadetails/java-0014.html

Executing another application from Java

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