package aula09.ex2; import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; public class CollectionTester { public static void main(String[] args) { int DIM = 5000; Collection col = new ArrayList<>(); checkPerformance(col, DIM); } private static void checkPerformance(Collection col, int DIM) { double start, stop, delta; // Add start = System.nanoTime(); // clock snapshot before for (int i = 0; i < DIM; i++) col.add(i); stop = System.nanoTime(); // clock snapshot after delta = (stop - start) / 1e6; // convert to milliseconds System.out.println(col.size() + ": Add to " + col.getClass().getSimpleName() + " took " + delta + "ms"); // Search start = System.nanoTime(); // clock snapshot before for (int i = 0; i < DIM; i++) { int n = (int) (Math.random() * DIM); if (!col.contains(n)) System.out.println("Not found???" + n); } stop = System.nanoTime(); // clock snapshot after delta = (stop - start) / 1e6; // convert nanoseconds to milliseconds System.out.println(col.size() + ": Search to " + col.getClass().getSimpleName() + " took " + delta + "ms"); // Remove start = System.nanoTime(); // clock snapshot before Iterator iterator = col.iterator(); while (iterator.hasNext()) { iterator.next(); iterator.remove(); } stop = System.nanoTime(); // clock snapshot after delta = (stop - start) / 1e6; // convert nanoseconds to milliseconds System.out.println(col.size() + ": Remove from " + col.getClass().getSimpleName() + " took " + delta + "ms"); } }