SetFromListPerfTest

SetFromListPerfTest.java

public class SetFromListPerfTest {

  @Test
  public void listToLinkedHashSetTest() throws Exception {

    final List<byte[]> data = buildListData();

    doTest(new Callback() {
      @Override
      public String name() {
        return "LinkedHashSet creation";
      }

      @Override
      public void test() {
        new LinkedHashSet<byte[]>(data);
      }
    });
  }

  @Test
  public void listToSetFromListTest() throws Exception {

    final List<byte[]> data = buildListData();

    doTest(new Callback() {
      @Override
      public String name() {
        return "SetFromList creation";
      }

      @Override
      public void test() {
        SetFromList.of(data);
      }
    });
  }

  @Test
  public void iterationLinkedHashSetTest() throws Exception {

    final Set<byte[]> s = new LinkedHashSet<byte[]>(buildListData());

    doTest(new Callback() {
      @Override
      public String name() {
        return "LinkedHashSet iteration";
      }

      @Override
      public void test() {
        for (byte[] x : s) {
          // skip
        }
      }
    });
  }

  @Test
  public void iterationSetFromListTest() throws Exception {

    final Set<byte[]> s = SetFromList.of(buildListData());

    doTest(new Callback() {
      @Override
      public String name() {
        return "SetFromList iteration";
      }

      @Override
      public void test() {
        for (byte[] x : s) {
          // skip
        }
      }
    });
  }

  private List<byte[]> buildListData() {

    List<byte[]> data = new ArrayList<byte[]>(1000000);
    for (int i = 0; i < 1000000; i++) {
      data.add(Integer.toString(i).getBytes());
    }
    return data;
  }

  private void doTest(Callback callback) {
    List<Long> elapseds = new ArrayList<Long>(10);

    for (int j = 1; j <= 10; j++) {

      System.gc();

      long start = System.currentTimeMillis();

      callback.test();

      long elapsed = System.currentTimeMillis() - start;
      elapseds.add(elapsed);
      System.out.println(callback.name() + " Timing : " + elapsed + " ms");
    }

    // remove outlier
    Collections.sort(elapseds);
    long sum = 0;

    for (int i = 0; i < elapseds.size() - 1; i++) {
      sum += elapseds.get(i);
    }

    System.out.println(callback.name() + " Timing avg : " + (sum / 9.0) + " ms");
  }

  static interface Callback {
    public String name();

    public void test();
  }
}