Java示例使用Method打印数组

import java.util.ArrayList;

import java.util.Vector;



public class Main {

   public static void main(String[] args) {

      Object testObject = new ArrayList();

      displayObjectClass(testObject);

   }

   public static void displayObjectClass(Object o) {

      if (o instanceof Vector) System.out.println(

         "Object was an instance of the class java.util.Vector");

      else if (o instanceof ArrayList) System.out.println(

         "Object was an instance of the class java.util.ArrayList");

      else System.out.println("Object was an instance of the " + o.getClass());

   }

}