How to Send Commands to Another Command-Line Program in Java?

How can I send commands to another command-line program using Java?

try {
    ProcessBuilder processBuilder = new ProcessBuilder("yourCommand");
    Process process = processBuilder.start();
    BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(process.getOutputStream()));
    writer.write("yourCommandArgument\n");
    writer.flush();
    writer.close();
} catch (IOException e) {
    e.printStackTrace();
}

In Java, you can communicate with another command-line program by using the `ProcessBuilder` and `Process` classes. These classes allow you to start a new process, send commands, and read the output or error streams of a running program.

ProcessBuilder processBuilder = new ProcessBuilder("yourCommand");
Process process = processBuilder.start();

BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(process.getOutputStream()));
writer.write("yourCommandArgument\n");
writer.flush();
writer.close();

Causes

• Incorrect command syntax.
• Issue with process input/output stream handling.
• Not properly closing the output stream after writing commands.

Solutions

• Use `ProcessBuilder` to create and manage the new process.
• Flush and close the output stream after sending commands.
• Read the input and error streams to handle responses from the command-line program.

Mistake: Failing to handle command output properly.

Solution: Always read the input stream for results and the error stream for any error messages.

Mistake: Not closing resources, leading to memory leaks.

Solution: Ensure to close InputStream, OutputStream, and Buffers in a finally block or use try-with-resources.