How to lock, shutdown, restart and suspend the pc with runtime.exec in java?

Question

How to lock, shutdown, restart and suspend the pc with runtime.exec in java?

I want to make a jar for windows and linux os.

I want to lock, shutdown, restart and suspend the pc programmatically.

I tried this code.

package poweroff;

import mousekeyboardcontrol.MouseKeyboardControl;


public class PowerOff {
String os;
Runtime runtime;
public PowerOff() {
    os = System.getProperty("os.name");
    runtime = Runtime.getRuntime();
}

public void shutdown() {     
    try {
        if ("Windows 8.1".equals(os) || "Windows 8.0".equals(os) || "Windows 10".equals(os)) {
            runtime.exec("shutdown -s");
        } else {
            System.out.println("Unsupported operating system");
        }
    } catch(Exception e) {
        System.out.println("shutdown error");
        e.printStackTrace();
    }
    
}

public void restart() {     
    try {
        if ("Windows 8.1".equals(os) || "Windows 8.0".equals(os) || "Windows 10".equals(os)) {
            runtime.exec("shutdown -r");
        } else {
            System.out.println("Unsupported operating system");
        }
    } catch(Exception e) {
        System.out.println("restart error");
        e.printStackTrace();
    }
    
}

public void suspend() {     
    try {
        if ("Windows 8.1".equals(os) || "Windows 8.0".equals(os) || "Windows 10".equals(os)) {
            runtime.exec("Rundll32.exe powrprof.dll,SetSuspendState Sleep");
        } else {
            System.out.println("Unsupported operating system");
        }
    } catch(Exception e) {
        System.out.println("suspend error");
        e.printStackTrace();
    }   
}

public void lock() {     
    try {
        if ("Linux".equals(os) || "Mac OS X".equals(os)) {
            new MouseKeyboardControl().ctrlAltL();
        } else if ("Windows 8.1".equals(os) || "Windows 8.0".equals(os) || "Windows 10".equals(os)) {
            runtime.exec("Rundll32.exe user32.dll,LockWorkStation");
        } else {
            System.out.println("Unsupported operating system");
        }
    } catch(Exception e) {
        System.out.println("pc lock error");
        e.printStackTrace();
    }
    
}

public static void main(String args[]) {
    PowerOff powerOff = new PowerOff();
    powerOff.lock();
}
}

But, it not worked.

I want to lock, shutdown, restart and suspend with programmatically in java for windows 7, 8, 10 and all linux os.

How can I solve this?

Answer 1

A solution could be to use the command line tools of each OS with appropriate flags. See here for instance for linux. See also this answer on another example Shutting down a computer

For Windows shutdown try: "shutdown -s -t 0" For Windows Restart try: "shutdown -r -t 0" For Windows Hibernate try: "shutdown -h -t 0"

For Linux shutdown try: "shutdown now" For Linux restart try: "reboot now"

Tip: If you can introduce dependencies, using SystemUtils from Apache Commons could help check the OS version correctly in an easy to read/maintain manner.