redis-投票

  1 package redis.inaction;
  2 
  3 import redis.clients.jedis.Jedis;
  4 import redis.clients.jedis.ZParams;
  5 
  6 import java.util.*;
  7 
  8 public class Chapter01 {
  9     private static final int ONE_WEEK_IN_SECONDS = 7 * 86400;
 10     private static final int VOTE_SCORE = 432;
 11     private static final int ARTICLES_PER_PAGE = 25;
 12 
 13     public static final void main(String[] args) {
 14         new Chapter01().run();
 15     }
 16 
 17     public void run() {
 18         Jedis conn = new Jedis("192.168.7.146",6379);
 19         conn.select(15);
 20         conn.flushAll();
 21         String articleId = postArticle(
 22             conn, "username", "A title", "http://www.google.com");
 23         System.out.println("We posted a new article with id: " + articleId);
 24         System.out.println("Its HASH looks like:");
 25         Map<String,String> articleData = conn.hgetAll("article:" + articleId);
 26         for (Map.Entry<String,String> entry : articleData.entrySet()){
 27             System.out.println("  " + entry.getKey() + ": " + entry.getValue());
 28         }
 29 
 30         System.out.println();
 31 
 32         articleVote(conn, "other_user", "article:" + articleId);
 33         String votes = conn.hget("article:" + articleId, "votes");
 34         System.out.println("We voted for the article, it now has votes: " + votes);
 35         assert Integer.parseInt(votes) > 1;
 36 
 37         System.out.println("The currently highest-scoring articles are:");
 38         List<Map<String,String>> articles = getArticles(conn, 1);
 39         printArticles(articles);
 40         assert articles.size() >= 1;
 41 
 42         addGroups(conn, articleId, new String[]{"new-group"});
 43         System.out.println("We added the article to a new group, other articles include:");
 44         articles = getGroupArticles(conn, "new-group", 1);
 45         printArticles(articles);
 46         assert articles.size() >= 1;
 47     }
 48 
 49     public String postArticle(Jedis conn, String user, String title, String link) {
 50         String articleId = String.valueOf(conn.incr("article:"));
 51 
 52         String voted = "voted:" + articleId;
 53         conn.sadd(voted, user);
 54         conn.expire(voted, ONE_WEEK_IN_SECONDS);
 55 
 56         long now = System.currentTimeMillis() / 1000;
 57         String article = "article:" + articleId;
 58         HashMap<String,String> articleData = new HashMap<String,String>();
 59         articleData.put("title", title);
 60         articleData.put("link", link);
 61         articleData.put("user", user);
 62         articleData.put("now", String.valueOf(now));
 63         articleData.put("votes", "1");
 64         conn.hmset(article, articleData);
 65         conn.zadd("score:", now + VOTE_SCORE, article);
 66         conn.zadd("time:", now, article);
 67 
 68         return articleId;
 69     }
 70 
 71     public void articleVote(Jedis conn, String user, String article) {
 72         long cutoff = (System.currentTimeMillis() / 1000) - ONE_WEEK_IN_SECONDS;
 73         if (conn.zscore("time:", article) < cutoff){
 74             return;
 75         }
 76 
 77         String articleId = article.substring(article.indexOf(':') + 1);
 78         if (conn.sadd("voted:" + articleId, user) == 1) {
 79             conn.zincrby("score:", VOTE_SCORE, article);
 80             conn.hincrBy(article, "votes", 1);
 81         }
 82     }
 83 
 84 
 85     public List<Map<String,String>> getArticles(Jedis conn, int page) {
 86         return getArticles(conn, page, "score:");
 87     }
 88 
 89     public List<Map<String,String>> getArticles(Jedis conn, int page, String order) {
 90          int start = (page - 1) * ARTICLES_PER_PAGE;
 91         int end = start + ARTICLES_PER_PAGE - 1;
 92 
 93         Set<String> ids = conn.zrevrange(order, start, end);
 94         List<Map<String,String>> articles = new ArrayList<Map<String,String>>();
 95         for (String id : ids){
 96             Map<String,String> articleData = conn.hgetAll(id);
 97             articleData.put("id", id);
 98             articles.add(articleData);
 99         }
100 
101         return articles;
102     }
103 
104     public void addGroups(Jedis conn, String articleId, String[] toAdd) {
105         String article = "article:" + articleId;
106         for (String group : toAdd) {
107             conn.sadd("group:" + group, article);
108         }
109     }
110 
111     public List<Map<String,String>> getGroupArticles(Jedis conn, String group, int page) {
112         return getGroupArticles(conn, group, page, "score:");
113     }
114 
115     public List<Map<String,String>> getGroupArticles(Jedis conn, String group, int page, String order) {
116         String key = order + group;
117         if (!conn.exists(key)) {
118             ZParams params = new ZParams().aggregate(ZParams.Aggregate.MAX);
119             conn.zinterstore(key, params, "group:" + group, order);
120             conn.expire(key, 60);
121         }
122         return getArticles(conn, page, key);
123     }
124 
125     private void printArticles(List<Map<String,String>> articles){
126         for (Map<String,String> article : articles){
127             System.out.println("  id: " + article.get("id"));
128             for (Map.Entry<String,String> entry : article.entrySet()){
129                 if (entry.getKey().equals("id")){
130                     continue;
131                 }
132                 System.out.println("    " + entry.getKey() + ": " + entry.getValue());
133             }
134         }
135     }
136 }

package redis.inaction;
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("192.168.7.146",6379); conn.select(15); conn.flushAll(); 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<String,String> articleData = conn.hgetAll("article:" + articleId); for (Map.Entry<String,String> 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<Map<String,String>> 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; }
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<String,String> articleData = new HashMap<String,String>(); 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; }
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<Map<String,String>> getArticles(Jedis conn, int page) { return getArticles(conn, page, "score:"); }
public List<Map<String,String>> getArticles(Jedis conn, int page, String order) { int start = (page - 1) * ARTICLES_PER_PAGE; int end = start + ARTICLES_PER_PAGE - 1;
Set<String> ids = conn.zrevrange(order, start, end); List<Map<String,String>> articles = new ArrayList<Map<String,String>>(); for (String id : ids){ Map<String,String> 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<Map<String,String>> getGroupArticles(Jedis conn, String group, int page) { return getGroupArticles(conn, group, page, "score:"); }
public List<Map<String,String>> 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); }
private void printArticles(List<Map<String,String>> articles){ for (Map<String,String> article : articles){ System.out.println(" id: " + article.get("id")); for (Map.Entry<String,String> entry : article.entrySet()){ if (entry.getKey().equals("id")){ continue; } System.out.println(" " + entry.getKey() + ": " + entry.getValue()); } } }}