public void testSort3(){
List<String>stringList2=new ArrayList<String>();
Random d=new Random();
String n="0123456789qwertyuiopasdfghkjlzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM";
String m="";
for(int j=0;j<10;j++){
m="";
Integer k=d.nextInt(9)+1;

        do{
            for(int i=0;i<k;i++){
    m=m+n.charAt(d.nextInt(62));    
    }
        }
        while(stringList2.contains(m));
        stringList2.add(m);
        }
    System.out.println("-----------排序前------------");
    for (String string : stringList2) {
            System.out.println("随机字符串："+string);
    }
    Collections.sort(stringList2);
    System.out.println("-----------排序后-----------");
    for (String string : stringList2) {
        System.out.println("随机字符串："+string);
    }
}