创建类型

import java.net.MalformedURLException;

import java.net.URL;// from N o w  J a v a  .   c o m

import java.util.ArrayList;

import java.util.List;


public class Main {

  public static void main(String[] args) throws Exception {

    List<Integer> intlist = new ArrayList<Integer>();


    intlist.add(new Integer(123));


    List<Number> numlist = new ArrayList<Number>();


    numlist.add(new Integer(123));

    numlist.add(new Float(123));

    intlist.add(null);

    List<URL> urlList = new ArrayList<URL>();

    try {//时 代 J a v a - nowjava.com

      urlList.add(