public?List<String>?randomIntList(){
????Random?random?=?new?Random();
????List<String>?list?=?new?ArrayList<String>();
????String?cur;
????for?(int?i?=?0;?i?<?3;?i++)?{
????????do?{
????????????cur?=?String.valueOf(random.nextInt(1000));
????????}while?(list.contains(cur));
????????list.add(cur);
????}
????return?list;
}
public?List<String>?randomStringList(int?len,?int?size){
????List<String>?list?=?new?ArrayList<String>();
????Integer?k;
????Random?random?=?new?Random();
????String?str?=?"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
????StringBuilder?stringBuilder?=?new?StringBuilder();
????for?(int?i?=?0;?i?<?len;?i++)?{
????????do?{
????????????for?(int?a?=?0;?a?<?size;?a++)?{
????????????????k?=?random.nextInt(str.length());
????????????????stringBuilder.append(str.charAt(k));
????????????}
????????}while?(list.contains(stringBuilder));
????????list.add(stringBuilder.toString());
????????stringBuilder.delete(0,stringBuilder.length());
????}
????return?list;
}
public?void?testSort()?{
????List<Student>?list?=?new?ArrayList<Student>();
????List<String>?randomIdList?=?this.randomIntList();
????List<String>?randomNameList?=?this.randomStringList(3,6);
????for?(int?i?=?0;?i?<?randomIdList.size();?i++)?{
????????list.add(new?Student(randomIdList.get(i),randomNameList.get(i)));
????}
????System.out.println("===========排序前=============");
????for?(Student?i:list)?{
????????System.out.println("元素:"+i.getId()+":"+i.getName());
????}
????Collections.sort(list);
????System.out.println("===========排序后=============");
????for?(Student?i:list)?{
????????System.out.println("元素:"+i.getId()+":"+i.getName());
????}
}
2019-07-07
感謝大佬