数据持久化

Question

我想知道我是否能得到一些关于我创建的库的反馈，以便在网上持久化数据。

JitterPushDemo.java

public class JitterPushDemo {

    public static void main(String[] args) {

        Jitter jitter = new Jitter("scores");


        // create hash map to map scores to players

        HashMap<String, String> map = new HashMap<String, String>();
        map.put("Bob", "300");
        map.put("Sam", "500");

        // push data online to jitter object
        jitter.pushData(map);

    }

}

JitterPullDemo.java

public class JitterPullDemo {

    public static void main(String[] args) {

        Jitter jitter = new Jitter("scores");

        // now pulling data from online and iterating
        for (Map.Entry<String, String> item: jitter.pullData().entrySet()) {
            System.out.println("Player: " + item.getKey());
            System.out.println("Scores: " + item.getValue());
        }  

    }

}

源代码

package org.main;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONObject;

public class Jitter {

    URL location;
    String thing;

    public Jitter(String thing) {
        this.thing = thing;
    }

    private void setLocation(String place) {

        try 
        {
            location = new URL(place);
            location.openConnection();
        }

        catch (Exception e) 
        {

        }

    }

    public String readData() {

        InputStream dataStream = null;
        InputStreamReader read = null;
        String result = ""; int value;

        try 
        {
            dataStream = location.openStream();
            read = new InputStreamReader(dataStream);

            while ((value = read.read()) != -1)
                result += String.valueOf((char) value);
        }

        catch (Exception e)
        {

        }

        return result;
    }

    public void pushData(HashMap<String, String> map) {

        String url = "https://dweet.io/dweet/for/" + thing + "?";

        for (Map.Entry<String, String> item : map.entrySet()) {
            String k = URLEncoder.encode(item.getKey());
            String v = URLEncoder.encode(item.getValue());
            String sub = k + '=' + v + "&"; url += sub;
        }

        try 
        {
            setLocation(url);
        }

        catch (Exception e) 
        {

        }

        readData();

    }

    public void pushData(String key, String value) {
        String url = "https://dweet.io/dweet/for/" + thing + "?";
        setLocation(url + key + "=" + value); readData();
    }

    public String pullData(String key) {

        setLocation("https://dweet.io/get/latest/dweet/for/" + thing);
        JSONArray main = new JSONObject(readData()).getJSONArray("with");
        JSONObject data = ((JSONObject) main.get(0)).getJSONObject("content");

        return data.optString(key);
    }

    public HashMap<String, String> pullData() {

        setLocation("https://dweet.io/get/latest/dweet/for/" + thing);
        JSONArray main = new JSONObject(readData()).getJSONArray("with");
        JSONObject data = ((JSONObject) main.get(0)).getJSONObject("content");

        HashMap<String, String> map = new HashMap<String, String>();

        for (String key : data.keySet()) {
            map.put(key, data.optString(key));
        }

        return map;
    }

}

Answer 1

• 一开始，您的代码不包含注释。注释对于了解代码的功能非常有用。
• 您的代码非常模糊。什么是字符串；//用户名？你有必要用更多的描述来描述这个问题。setLocation()我注意到它设置了子目录。你可以说得更具体些。
• 在Netbeans 8中，URLEncoder.encode被标记为不推荐使用。您可能需要考虑一种更前向兼容的替代方案:公共静态字符串编码(字符串s，字符串enc)；
• 字符串都是硬编码的。当您将所有这些类型的东西放在一个地方时，维护代码就容易多了。
• 你在吃你的错误。这太糟了。错误告诉你出了什么问题。当你吃错误的时候，你会引起众神的愤怒；你永远不会知道你的代码何时不起作用。