How I can use CMD Command in Java program?

Question

I want to use cmd Commands in java program,

Want to crope all images in folder, I downlaoded ImageMagick, and using cmd commands Its working 1 image,

cd C:\Users\Robert\Java-workspace\Crop_test\Crop_test1
cd  convert -crop 312x312+0-10 image1.jpg new_image1.jpg

But, I want to use this in Java so, I can crop all images in folder by program, Here is my java program:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import org.omg.CORBA.portable.OutputStream;

 public class test1 {
    public static void main(String argv[]) throws IOException, InterruptedException {

        ProcessBuilder pb = new ProcessBuilder("cmd", "/c", "C:\\Users\\Robert\\Java-workspace\\Crop_test\\Crop_test1\\", "convert -crop 312x312+0-10 image1.jpg new_image1.jpg"); 
        Process p = pb.start();
        p.waitFor();
    }
}

Answer 1

Although you are asking how to use CMD and this was addressed on other answers I think that the best solution (considering your explanation of your implementation) would be to use a ImageMagick wrapper for Java as you can see here.

Cheers

Answer 2

You can invoke CMD commands as follows in Java;

Runtime.getRuntime().exec(your_command);

Best thing for you to do is to creat a batch file with the commands you need to run and then invoke your batch file using the following command;

Runtime.getRuntime().exec("cmd /C start D:\\test.bat");

because you cannot do any change directory commands using the Runtime class. Please try this option and let me know if you face any other issues.

Answer 3

A couple of things to try (both of which are untested):

1. Put a cd in the command line and use && to run both commands in one line.

   import java.io.BufferedReader;
   import java.io.IOException;
   import java.io.InputStreamReader;
   
   import org.omg.CORBA.portable.OutputStream;
   
    public class test1 {
       public static void main(String argv[]) throws IOException, InterruptedException {
   
           ProcessBuilder pb = new ProcessBuilder("cmd", "/c", "cd C:\\Users\\Robert\\Java-workspace\\Crop_test\\Crop_test1\\ && convert -crop 312x312+0-10 image1.jpg new_image1.jpg"); 
           pb.redirectErrorStream(true);
           Process p = pb.start();
           p.waitFor();
       }
   }
   

2. Change the directory that the ProcessBuilder starts in:

   import java.io.BufferedReader;
   import java.io.IOException;
   import java.io.InputStreamReader;
   
   import org.omg.CORBA.portable.OutputStream;
   
    public class test1 {
       public static void main(String argv[]) throws IOException, InterruptedException {
   
           ProcessBuilder pb = new ProcessBuilder("cmd", "/c", "convert -crop 312x312+0-10 image1.jpg new_image1.jpg");
           pb.directory(new File("C:\\Users\\Robert\\Java-workspace\\Crop_test\\Crop_test1\\"));
           pb.redirectErrorStream(true);
           Process p = pb.start();
           p.waitFor();
       }
   }
   

Incidentally, are you sure you want to import org.omg.CORBA.portable.OutputStream? Did you mean java.io.OutputStream instead?

EDIT: if things still aren't working, then the next step is to see whether the problem is that convert isn't being found. Let's just run convert on its own without any arguments and see if it spits out its usage message to standard output. Run the following:

public class test1 {
    public static void main(String argv[]) throws IOException, InterruptedException {

        ProcessBuilder pb = new ProcessBuilder("cmd.exe", "/c", "convert");
        pb.redirectErrorStream(true);
        Process p = pb.start();
        StreamGobbler g = new StreamGobbler(p.getInputStream(), "OUT");
        g.start();
        p.waitFor();
    }
}

Use the StreamGobbler class here. Does this print out convert's usage method, with each line prefixed with OUT>?