package com.imooc;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Random;
public class CollectionSort {
ArrayList<String> RandomList = new ArrayList<String>();
/**
* 向ArrayList中添加字符串
*/
public void addList() {
String str;
for (int i = 0; i < 10; i++) {
do {
str = getString();
} while (RandomList.contains(str));
RandomList.add(str);
System.out.println("成功添加:"+str);
}
}
/**
* 排序
*/
public void sortCollection() {
System.out.println("--------排序前--------");
for (String string : RandomList) {
System.out.println("随机数列:"+string);
}
System.out.println("--------排序后--------");
Collections.sort(RandomList);
for (String string : RandomList) {
System.out.println("随机数列:"+string);
}
}
/**
* 生成长度10以内的随机字符串
* @return
*/
public String getString() {
Random random = new Random();
String str = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRST";
StringBuilder sb = new StringBuilder();
int length = str.length();
do {
int ran = random.nextInt(length);
sb.append(str.charAt(ran));
} while (sb.length() < random.nextInt(10));
return sb.toString();
}
//生成3个1000以内的不重复的数字
public void third(){
int i = 1;
Random random = new Random();
int[] id =new int[3];
id[0]=random.nextInt(1000);
while(i<3){
if(id[i] != random.nextInt(1000)){
id[i] = random.nextInt(1000);
}else{
continue;
}
i++;
}
for (int j : id) {
System.out.println(j);
}
}
public static void main(String[] args) {
CollectionSort cs = new CollectionSort();
cs.addList();
cs.sortCollection();
// cs.third();
}
}