用本地txt当简易数据库

本文使用流进行存储和读取，有兴趣深入研究的小伙伴去看看java io流

	//写数据
	public String writeTxt(String planId,String name){
        try {
            //如果文件存在，则追加内容；如果文件不存在，则创建文件
            File f = new File("NameAndId.txt");
            FileWriter fw = new FileWriter(f, true);
            PrintWriter pw = new PrintWriter(fw);
            //java数据，可以转成json字符串存储
            String dataString = "{\"planId\":\""+planId+"\",\"name\":\""+name+"\"}";
            pw.println(dataString);
            pw.flush();
            pw.close();
            fw.close();
            return "success";
        } catch (IOException e) {
            e.printStackTrace();
        }
        return "failure";
    }

    //读数据：获取本地文件中最后一行数据
    public String readTxt() {
        try {
            String path = "NameAndId.txt";
            BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(new File(path)), "UTF-8"));
            String lineTxt = null;
            List<String> list = new ArrayList<String>();
            int count = 0;
            // 逐行读取
            while ((lineTxt = br.readLine()) != null) {
                list.add(lineTxt);
            }
            System.out.println("这是最后一个"+list.get(list.size()-1));
            br.close();
            return list.get(list.size()-1);
        } catch (Exception e) {
            System.out.println(e);
        }
        return "failure";
    }