Dummy benchmark

ClassWithNakedConstructorInstantiationBenchMark.java

package com.company;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Random;

public class ClassWithNakedConstructorInstantiationBenchMark {
  static final int COUNT = 1000000;
  static final String CLASS_NAME = HelloWorld.class.getName();

  public static void main(String[] args)
      throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException,
      InvocationTargetException, InstantiationException {
    // dummy warming up
    Random random = new Random();
    for (int i=0; i < 100; ++i) {
      random.nextInt();
      random.nextBoolean();
    }

    normalWay();
    callStaticMethod();
    newInstance();
    constructorThenNewInstance();

    System.out.println("\n");

    normalWay();
    constructorThenNewInstance();
    newInstance();
    callStaticMethod();

    System.out.println("\n");

    normalWay();
    constructorThenNewInstance();
    callStaticMethod();
    newInstance();
  }

  private static void normalWay() {
    long start = System.currentTimeMillis();
    for (int i = 0; i < COUNT; ++i) {
      HelloWorld hw = new HelloWorld();
      hw.d2Method1();
    }
    long end = System.currentTimeMillis();
    System.out.printf("[%d] Normal way\n", end - start);
  }

  private static void callStaticMethod()
      throws NoSuchMethodException, ClassNotFoundException, IllegalAccessException,
      InvocationTargetException {
    long start = System.currentTimeMillis();
    for (int i = 0; i < COUNT; ++i) {
      Method m1 = Class.forName(CLASS_NAME).getMethod("s2Method1");
      m1.invoke(null);
    }
    long end = System.currentTimeMillis();
    System.out.printf("[%d] Use static method\n", end - start);
  }

  private static void newInstance()
      throws InstantiationException, IllegalAccessException, ClassNotFoundException {
    long start = System.currentTimeMillis();
    for (int i = 0; i < COUNT; ++i) {
      HelloWorld hw1 =
          (HelloWorld) Class.forName(CLASS_NAME).newInstance();
      hw1.d2Method1();
    }
    long end = System.currentTimeMillis();
    System.out.printf("[%d] Use newInstance\n", end - start);
  }

  private static void constructorThenNewInstance()
      throws InstantiationException, IllegalAccessException, InvocationTargetException,
      NoSuchMethodException, ClassNotFoundException {
    long start = System.currentTimeMillis();
    for (int i = 0; i < COUNT; ++i) {
      HelloWorld hw1 =
          (HelloWorld) Class.forName(CLASS_NAME).getConstructor().newInstance();
      hw1.d2Method1();
    }
    long end = System.currentTimeMillis();
    System.out.printf("[%d] Use getConstructor().newInstance()\n", end - start);
  }

  public static class HelloWorld extends HelloWorld1 {
    public HelloWorld() {}
    public HelloWorld(String s) {}
    public HelloWorld(Integer i) {}
    public HelloWorld(Double d) {}
    public HelloWorld(Float f) {}

    public static HelloWorld getInstance() {
      return new HelloWorld();
    }

    public static void s2Method1() { }
    public static void s2Method2() { }
    public static void s2Method3() { }
    public static void s2Method4() { }
    public static void s2Method5() { }
    public static void s2Method6() { }
    public static void s2Method7() { }
    public static void s2Method8() { }
    public static void s2Method9() { }

    public void dMethod1() { }
    public void dMethod2() { }
    public void dMethod3() { }
    public void dMethod4() { }
    public void dMethod5() { }
    public void dMethod6() { }
    public void dMethod7() { }
    public void dMethod8() { }
    public void dMethod9() { }
  }

  public static class HelloWorld1 extends HelloWorld2 {
    public HelloWorld1() {}
    public HelloWorld1(String s) {}
    public HelloWorld1(Integer i) {}
    public HelloWorld1(Double d) {}
    public HelloWorld1(Float f) {}

    public static void sMethod1() { }
    public static void sMethod2() { }
    public static void sMethod3() { }
    public static void sMethod4() { }
    public static void sMethod5() { }
    public static void sMethod6() { }
    public static void sMethod7() { }
    public static void sMethod8() { }
    public static void sMethod9() { }

    public void d1Method1() { }
    public void d1Method2() { }
    public void d1Method3() { }
    public void d1Method4() { }
    public void d1Method5() { }
    public void d1Method6() { }
    public void d1Method7() { }
    public void d1Method8() { }
    public void d1Method9() { }
  }

  public static class HelloWorld2 extends HelloWorld3 {
    public HelloWorld2() {}
    public HelloWorld2(String s) {}
    public HelloWorld2(Integer i) {}
    public HelloWorld2(Double d) {}
    public HelloWorld2(Float f) {}

    public static void s2Method1() { }
    public static void s2Method2() { }
    public static void s2Method3() { }
    public static void s2Method4() { }
    public static void s2Method5() { }
    public static void s2Method6() { }
    public static void s2Method7() { }
    public static void s2Method8() { }
    public static void s2Method9() { }

    public void d2Method1() { }
    public void d2Method2() { }
    public void d2Method3() { }
    public void d2Method4() { }
    public void d2Method5() { }
    public void d2Method6() { }
    public void d2Method7() { }
    public void d2Method8() { }
    public void d2Method9() { }
  }

  public static class HelloWorld3 extends HelloWorld4 {
    public HelloWorld3() {}
    public HelloWorld3(String s) {}
    public HelloWorld3(Integer i) {}
    public HelloWorld3(Double d) {}
    public HelloWorld3(Float f) {}

    public static void s2Method1() { }
    public static void s2Method2() { }
    public static void s2Method3() { }
    public static void s2Method4() { }
    public static void s2Method5() { }
    public static void s2Method6() { }
    public static void s2Method7() { }
    public static void s2Method8() { }
    public static void s2Method9() { }

    public void d3Method1() { }
    public void d3Method2() { }
    public void d3Method3() { }
    public void d3Method4() { }
    public void d3Method5() { }
    public void d3Method6() { }
    public void d3Method7() { }
    public void d3Method8() { }
    public void d3Method9() { }
  }

  public static class HelloWorld4 {
    public HelloWorld4() {}
    public HelloWorld4(String s) {}
    public HelloWorld4(Integer i) {}
    public HelloWorld4(Double d) {}
    public HelloWorld4(Float f) {}


    public static void s2Method1() { }
    public static void s2Method2() { }
    public static void s2Method3() { }
    public static void s2Method4() { }
    public static void s2Method5() { }
    public static void s2Method6() { }
    public static void s2Method7() { }
    public static void s2Method8() { }
    public static void s2Method9() { }

    public void d4Method1() { }
    public void d4Method2() { }
    public void d4Method3() { }
    public void d4Method4() { }
    public void d4Method5() { }
    public void d4Method6() { }
    public void d4Method7() { }
    public void d4Method8() { }
    public void d4Method9() { }
  }
}