Class对象

Posted 2020-10-29 来自IT国的猴子

package typeinfo;//: typeinfo/SweetShop.java
// Examination of the way the class loader works.
import static net.mindview.util.Print.*;

class Candy {
  static { print("Loading Candy"); }
}

class Gum {
  static { print("Loading Gum"); }
}

class Cookie {
  static { print("Loading Cookie"); }
}

public class SweetShop {
  public static void main(String[] args) {    
    print("inside main");
    new Candy();
    print("After creating Candy");
    try {
      Class.forName("Gum");
    } catch(ClassNotFoundException e) {
      print("Couldn‘t find Gum");
    }
    print("After Class.forName(\"Gum\")");
    new Cookie();
    print("After creating Cookie");
  }
} /* Output:
inside main
Loading Candy
After creating Candy
Loading Gum
After Class.forName("Gum")
Loading Cookie
After creating Cookie
*///:~

这里的每一个类都有一个static，当类被加载时自动执行static的代码

 Class.forName("Gum");这个语句也会执行Gum这个类中的代码