Check if android device is rooted programmatically

import android.os.Build;
import java.io.File;

public class UtilCheckIcon {
    public static boolean isDeviceRooted() {
        return checkRootMethod1() || checkRootMethod2() || checkRootMethod3();
    }

    private static boolean checkRootMethod1() {
        String str = Build.TAGS;
        return str != null && str.contains("test-keys");
    }

    private static boolean checkRootMethod2() {
        String[] strArr = {"/system/app/Superuser.apk", "/sbin/su", "/system/bin/su", "/system/xbin/su", "/data/local/xbin/su", "/data/local/bin/su", "/system/sd/xbin/su", "/system/bin/failsafe/su", "/data/local/su", "/su/bin/su"};
        for (int i = 0; i < 10; i++) {
            if (new File(strArr[i]).exists()) {
                return true;
            }
        }
        return false;
    }

   private static boolean checkRootMethod3() {
       return new File("/system/app/Superuser.apk").exists();
   }