If we want to measure time of code execution then we can get the time as long (in milliseconds) before and after specific code execution and find the difference which will give us the answer how long a code execution take.
Lest see example program:
package org.example;
public class Main {
public static void main(String[] args) throws InterruptedException {
System.out.println("Start of the program");
final long startTime = System.currentTimeMillis();
// Here the measurements are done
// For testing reasons we make the thread sleep for 1 second
Thread.sleep(1000L);
final long endTime = System.currentTimeMillis();
System.out.println("Execution time in milliseconds: " + (endTime - startTime));
}
}
And the result is:
Start of the program
Execution time in milliseconds: 1000