redis in action javaコード追加コメント——Chapter 01

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redis in action
redis in actionを読みますhttps://github.com/josiahcarlson/redis-in-actionここでjavaコードをダウンロードして、いくつかの注釈を追加して、記憶を助けます
/**
 * 'article:'       ，       ID

 * voted:ID set  ，     

 * article:ID HASH   ，         

 * score: ZSET   (article:ID ，  ) 

 * time:ZSET   (article:ID ，    )

 * group:   set         

 * */
import redis.clients.jedis.Jedis;
import redis.clients.jedis.ZParams;

import java.util.*;

public class Chapter01 {
    private static final int ONE_WEEK_IN_SECONDS = 7 * 86400;
    private static final int VOTE_SCORE = 432;
    private static final int ARTICLES_PER_PAGE = 25;

    public static final void main(String[] args) {
        new Chapter01().run();
    }

    public void run() {
        Jedis conn = new Jedis("192.168.154.129", 6379);
        conn.auth("password");
        conn.select(15);

        //    
        String articleId = postArticle(conn, "username", "A title", "http://www.google.com");
        System.out.println("We posted a new article with id: " + articleId);
        System.out.println("Its HASH looks like:");
        Map articleData = conn.hgetAll("article:" + articleId);
        for (Map.Entry entry : articleData.entrySet()) {
            System.out.println("  " + entry.getKey() + ": " + entry.getValue());
        }

        System.out.println();

        //    
        articleVote(conn, "other_user", "article:" + articleId);
        String votes = conn.hget("article:" + articleId, "votes");
        System.out.println("We voted for the article, it now has votes: " + votes);
        assert Integer.parseInt(votes) > 1;

        System.out.println("The currently highest-scoring articles are:");
        //        
        List> articles = getArticles(conn, 1);
        //   
        printArticles(articles);
        assert articles.size() >= 1;

        //   
        addGroups(conn, articleId, new String[] { "new-group" });
        System.out.println("We added the article to a new group, other articles include:");
        //            
        articles = getGroupArticles(conn, "new-group", 1);
        printArticles(articles);
        assert articles.size() >= 1;
    }

    /**
     *        、  ，    ID
     * 
     * @param conn
     *            jedis   
     * @param user
     *               
     * @param title
     *              
     * @param link
     *                
     * @return   ID
     */
    public String postArticle(Jedis conn, String user, String title, String link) {
        String articleId = String.valueOf(conn.incr("article:"));

        //         
        String voted = "voted:" + articleId;
        conn.sadd(voted, user);
        conn.expire(voted, ONE_WEEK_IN_SECONDS);

        //        
        long now = System.currentTimeMillis() / 1000;
        String article = "article:" + articleId;
        HashMap articleData = new HashMap();
        articleData.put("title", title);
        articleData.put("link", link);
        articleData.put("user", user);
        articleData.put("now", String.valueOf(now));
        articleData.put("votes", "1");
        conn.hmset(article, articleData);
        conn.zadd("score:", now + VOTE_SCORE, article);
        conn.zadd("time:", now, article);

        return articleId;
    }

    /**
     *      
     * 
     * @param user
     *               
     * @param article
     *               'article:'+id
     */
    public void articleVote(Jedis conn, String user, String article) {
        //         
        long cutoff = (System.currentTimeMillis() / 1000) - ONE_WEEK_IN_SECONDS;
        if (conn.zscore("time:", article) < cutoff) {
            return;
        }

        String articleId = article.substring(article.indexOf(':') + 1);
        //         ，         
        if (conn.sadd("voted:" + articleId, user) == 1) {
            conn.zincrby("score:", VOTE_SCORE, article);
            conn.hincrBy(article, "votes", 1);
        }
    }

    public List> getArticles(Jedis conn, int page) {
        return getArticles(conn, page, "score:");
    }

    /**
     *    ZSET      ， page    ；      ；
     * 
     * @param page
     *              -- 1  
     * @parma order SZET
     * @return List>
     */
    public List> getArticles(Jedis conn, int page, String order) {
        int start = (page - 1) * ARTICLES_PER_PAGE;
        int end = start + ARTICLES_PER_PAGE - 1;

        Set ids = conn.zrevrange(order, start, end);
        List> articles = new ArrayList>();
        for (String id : ids) {
            Map articleData = conn.hgetAll(id);
            articleData.put("id", id);
            articles.add(articleData);
        }

        return articles;
    }

    //
    public void addGroups(Jedis conn, String articleId, String[] toAdd) {
        String article = "article:" + articleId;
        for (String group : toAdd) {
            conn.sadd("group:" + group, article);
        }
    }

    public List> getGroupArticles(Jedis conn, String group, int page) {
        return getGroupArticles(conn, group, page, "score:");
    }

    public List> getGroupArticles(Jedis conn, String group, int page, String order) {
        String key = order + group;
        if (!conn.exists(key)) {
            ZParams params = new ZParams().aggregate(ZParams.Aggregate.MAX);
            conn.zinterstore(key, params, "group:" + group, order);
            conn.expire(key, 60);
        }
        return getArticles(conn, page, key);
    }

    //   ，id    
    private void printArticles(List> articles) {
        for (Map article : articles) {
            System.out.println("  id: " + article.get("id"));
            for (Map.Entry entry : article.entrySet()) {
                if (entry.getKey().equals("id")) {
                    continue;
                }
                System.out.println("    " + entry.getKey() + ": " + entry.getValue());
            }
        }
    }
}
MVVM
Prototype Chain