public class Example_014 {

  class Person{
    String name;
    int age;
    public Person(String name, int age) {
      this.name = name;
      this.age = age;
    }
    // example start
    public String toString() {
      return new String(name + ":" + age);
    }
    // fixed code
    public String toString2() {
      return name + ":" + age;
    }
    // example end
  }
  // test start
  public static void main(String[] args) {
    Example_014 test = new Example_014();
    test.time(100000, false); // to warm up jvm
    test.time(100000, true);
  }
  boolean print = false;
  private long stamp;
  private void time(int n, boolean p) {
    print = p;
    start();
    Person bob = new Person("bob", 18);
    for (int i = 0; i < n; i++) {
      bob.toString();
    }
    time("with extra constructor");
    for (int i = 0; i < n; i++) {
      bob.toString2();
    }
    time("fixed");
  }
  private void start() {
    stamp = System.currentTimeMillis();
  }
  private void time(String m) {
    long a1 = System.currentTimeMillis() - stamp;
    if (print) {
      System.out.println(a1 + " ms for " + m);
    }
    System.gc();
    start();
  }