Execute Command Prompt Commands in Java

Problem:

Running command prompt commands through Java can be challenging. Although you may find code snippets that open the command prompt, they often lack the ability to change directories and execute additional commands.

Solution:

To run command prompt commands and change directories using Java, utilize a ProcessBuilder. This approach allows you to:

• Start a process and redirect its standard error to its standard output.
• Change directory and execute commands in a single command line.

Code Example:

import java.io.*;

public class CmdRunner {
    public static void main(String[] args) throws Exception {
        ProcessBuilder builder = new ProcessBuilder(
            "cmd.exe", "/c", "cd \"C:\\Program Files\\Flowella\" && dir");
        builder.redirectErrorStream(true);
        Process p = builder.start();

        BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
        String line;
        while ((line = r.readLine()) != null) {
            System.out.println(line);
        }
    }
}

This code:

• Utilizes a ProcessBuilder to run the "cd" and "dir" commands.
• Redirects the process's standard error into its standard output for a single read stream.
• Prints the output to the console.