Current system time
static long nanoTime()- Returns the current value of the most precise available system timer, in nanoseconds.
static long currentTimeMillis()- Returns the current time in milliseconds.
public class Main {
public static void main(String args[]) {
System.out.println(System.nanoTime());
System.out.println(System.currentTimeMillis());
}
}
The output:
238819728662434
1288461269875
The following code uses the System.currentTimeMillis() to check the performance of a for loop.
public class Main {
public static void main(String args[]) {
long start, end;
System.out.println("Timing a for loop from 0 to 1,000,000");
start = System.currentTimeMillis(); // get starting time
for (int i = 0; i < 9999999; i++)
;
end = System.currentTimeMillis(); // get ending time
System.out.println("Elapsed time: " + (end - start));
}
}
The output:
Timing a for loop from 0 to 1,000,000
Elapsed time: 16