Collections 类的方法总结

public class TestCollect {
?public static void main(String[] args){
???????? ArrayList al=new ArrayList();
???????? al.add("6");
???????? al.add("8");
???????? al.add("3");
???????? al.add("1");
????????
//?????? Collections.max(al)的用法
//???????? System.out.println("集合中的最大值："+Collections.max(al));
//???????? System.out.println("------------------------------------");
//???????? Collections.min(al)的用法
//???????? System.out.print("集合中的最小值："+Collections.min(al));
????????
//?????? Collections.sort(al);的用法。
//???????? Collections.sort(al);
//???????? for(int i=0;i<al.size();i++){
//??????? ?System.out.println(al.get(i));
//???????? }
????????
//????????? Collections.reverse(al);
//????????? for(int i=0;i<al.size();i++){
//???? ?? System.out.println(al.get(i));
//????? }
????????
????????
????????
?????
//?????? Arrays.sort(s, Collections.reverseOrder());对数组从大到小排序的方法。?
//???????? String[] s ={"d","a","e","c","b"};
//???????? Arrays.sort(s, Collections.reverseOrder());
//????????
//???????? for(int i=0;i<s.length;i++){
//??????? ? System.out.println(s[i]);
//???????? }
????????
//???????? 随机排序的输出
//?????????? ?Collections.shuffle(al);
//??????????? for(int i=0;i<al.size();i++){
//??????? ?System.out.println(al.get(i));
//???????? }
???????????
??????????? Random r = new Random(System.currentTimeMillis());
??????????? Collections.shuffle(al,r);
??????????? for(int i=0;i<al.size();i++){
??????????? ?System.out.println(al.get(i));
???????? }
?}
}