Java写数据到TXT（满n行写入新TXT）

public class FileUtil {




    public static void main(String[] args) {
        
        List userList=new ArrayList<>();
        User user1=new User("000001","黎明1","123456");
        User user2=new User("000002","黎明2","123456");
        User user3=new User("000003","黎明3","123456");
        User user4=new User("000004","黎明4","123456");
        User user5=new User("000010","黎明5","123456");
        User user6=new User("000011","黎明6","123456");
        User user7=new User("000021","黎明7","123456");
        User user8=new User("000031","黎明8","123456");
        User user9=new User("000041","黎明9","123456");

        userList.add(user1);
        userList.add(user2);
        userList.add(user3);
        userList.add(user4);
        userList.add(user5);
        userList.add(user6);
        userList.add(user7);
        userList.add(user8);
        userList.add(user9);

        writeContext(userList,4);
    }

    public static  void writeContext(List userList,int length){
        if(userList.size()>length){
            List> splitList = splitList(userList, length);
            splitList.forEach(users -> writeObjectToTxt(users));
        }
    }

    /**
     * 写数据到txt
     * @param userList
     */
    private static void writeObjectToTxt(List userList){
        File file=new File("/home/caozg/"+System.currentTimeMillis()+".txt");
        if(!file.exists()){
            try {
                file.createNewFile();
                BufferedWriter bufferedWriter=new BufferedWriter(new FileWriter(file));

                userList.forEach(user -> {
                    try {
                        bufferedWriter.write(user.toString());
                        bufferedWriter.newLine();
                    } catch (IOException e) {
                        System.out.println("写数据异常");
                    }
                });
                bufferedWriter.flush();
                bufferedWriter.close();
            } catch (IOException e) {
                System.out.println("文件创建失败");
            }
        }

    }

    /**
     * 按长度切割List
     * @param list  源List
     * @param len   切割的长度
     * @return
     */
    private static List> splitList(List list, int len) {
        if (list == null || list.size() == 0 || len < 1) {
            return null;
        }
        List> result = new ArrayList<>();
        int size = list.size();
        int count = (size + len - 1) / len;
        for (int i = 0; i < count; i++) {
            List subList = list.subList(i * len, ((i + 1) * len > size ? size : len * (i + 1)));
            result.add(subList);
        }
        return result;
    }


}