JAVA.util.List

常用方法

public static void main(String[] args) {
		List list1=new ArrayList();
		list1.add(11);
		list1.add("fdfsf");
		//输出 1
		System.out.println(list1);
		//输出 2
		 int n=list1.size();
		 for(int i=0;i<n;i++) {
			 System.out.println(list1.get(i));
		 }
		//输出 3
		 for(Object t:list1) {
			 System.out.print(t+" ");
		 }
		 System.out.println();
	
	}
	 //输出4
		 Iterator it = list1.iterator();
		 while(it.hasNext()) {
			 Object object=it.next();
			 System.out.println(object);
		 }

 Set list1=new HashSet();//元素不能重复