网易云音乐功能分析
1.存储所有歌曲(评论数)
2.一首歌对应多个评论
3.每个评论可以点赞 根据点赞数排序
4.歌单 歌单中的歌曲已热度排序(评论数*432 + 喜欢这首歌的人*432 (比例还可以调整) + 发布时间)
5.我喜欢的歌
解决方案
1.使用Hash存储歌的具体信息 使用String存储ID
2.使用Set存储每首歌对应的评论ID
3.使用ZSet
4.使用Set存储歌曲ID
5.使用java反射
pojo:
评论实体类
1 public class Comment {
2
3 private String id;
4
5 private String comment;
6
7 private String time;
8
9 private String good;
10
11 public Comment() {
12 }
13
14 public String getId() {
15 return id;
16 }
17
18 public void setId(String id) {
19 this.id = id;
20 }
21
22 public String getComment() {
23 return comment;
24 }
25
26 public void setComment(String comment) {
27 this.comment = comment;
28 }
29
30 public String getTime() {
31 return time;
32 }
33
34 public void setTime(String time) {
35 this.time = time;
36 }
37
38 public String getGood() {
39 return good;
40 }
41
42 public void setGood(String good) {
43 this.good = good;
44 }
45 }
歌曲实体类
1 public class Song {
2
3 private String id;
4
5 private String name;
6
7 private String singer;
8
9 private String comments;
10
11 private List<Comment> commentList;
12
13 public Song() {
14 }
15
16 public Song(String name, String singer) {
17 this.name = name;
18 this.singer = singer;
19 this.comments = "0";
20 }
21
22 public String getId() {
23 return id;
24 }
25
26 public void setId(String id) {
27 this.id = id;
28 }
29
30 public String getName() {
31 return name;
32 }
33
34 public void setName(String name) {
35 this.name = name;
36 }
37
38 public String getSinger() {
39 return singer;
40 }
41
42 public void setSinger(String singer) {
43 this.singer = singer;
44 }
45
46 public String getComments() {
47 return comments;
48 }
49
50 public void setComments(String comments) {
51 this.comments = comments;
52 }
53
54 public List<Comment> getCommentList() {
55 return commentList;
56 }
57
58 public void setCommentList(List<Comment> commentList) {
59 this.commentList = commentList;
60 }
61 }
新增歌曲
1 // 新增歌曲
2 private String addSong(Jedis conn, Song song) {
3 // 获取歌曲ID
4 // ID不存在会创建一个(1) 存在则会自增
5 String id = String.valueOf(conn.incr("song:"));
6
7 //将歌曲存入hash中
8 String key = "song:" + id;
9 HashMap<String, String> map = new HashMap<String, String>();
10 map.put("id", id);
11 map.put("name", song.getName());
12 map.put("singer", song.getSinger());
13 map.put("comments", String.valueOf(song.getComments()));
14 conn.hmset(key, map);
15
16 //记录热度 初始化成当前时间
17 conn.zadd("hot:", now(), key);
18 return id;
19 }
增加评论
1 // 增加评论
2 private void addComment(Jedis conn, String id, String comment) {
3 String songKey = "song:" + id;
4 //歌曲信息中评论还是加1
5 conn.hincrBy(songKey, "comments", 1);
6 //增加热度
7 conn.zincrby("hot:", VOTE_SCORE, songKey);
8
9 String commentKey = "song:" + id + " comments:";
10
11 //获取评论id
12 String commentID = String.valueOf(conn.incr(commentKey));
13
14 commentKey += commentID;
15
16 HashMap<String, String> map = new HashMap<String, String>();
17 map.put("id", commentID);
18 map.put("comment", comment);
19 map.put("time", time());
20 map.put("good", "0");
21
22 conn.hmset(commentKey, map);
23
24 //默认给自己点个赞
25 conn.zadd("song:" + id + " score:", 1, "comments:" + commentID);
26 }
评论点赞
1 //点赞
2 private void good(Jedis conn, String song, String comment) {
3 //增加点赞数(排名)
4 conn.zincrby("song:" + song + " score:", 1, "comments:" + comment);
5 //hash中记录
6 conn.hincrBy("song:" + song + " comments:" + comment, "good", 1);
7 //增加歌曲热度
8 conn.zincrby("hot:", VOTE_SCORE, "song:" + song);
9 }
查询歌曲
1 //按照热度获取歌曲
2 private List<Song> song(Jedis conn) {
3 Set<String> set = conn.zrevrange("hot:", 0, -1);
4 List<Song> list = new ArrayList<>();
5 for (String str : set) {
6 list.add(get(conn.hgetAll(str), conn));
7 }
8 return list;
9 }
10
11 private Song get(Map<String, String> map, Jedis conn) {
12 Class<Song> clazz = Song.class;
13 Song song = null;
14 try {
15 song = clazz.newInstance();
16 } catch (InstantiationException | IllegalAccessException e) {
17 e.printStackTrace();
18 }
19 for (Map.Entry<String, String> entry : map.entrySet()) {
20 try {
21 Field field = clazz.getDeclaredField(entry.getKey());
22 if (entry.getKey().equals("id")) {
23 String key = "song:" + entry.getValue() + " score:";
24 Set<String> set = conn.zrevrange(key, 0, -1);
25 List<Comment> list = new ArrayList<>();
26 for (String str : set) {
27 list.add(getComment(conn.hgetAll("song:" + entry.getValue() + " " + str)));
28 }
29 Field commentList = clazz.getDeclaredField("commentList");
30 commentList.setAccessible(true);
31 commentList.set(song, list);
32 }
33 field.setAccessible(true);
34 field.set(song, entry.getValue());
35 } catch (IllegalAccessException | NoSuchFieldException e) {
36 e.printStackTrace();
37 }
38 }
39 return song;
40 }
41
42 private Comment getComment(Map<String, String> map) {
43 Class<Comment> clazz = Comment.class;
44 Comment comment = null;
45 try {
46 comment = clazz.newInstance();
47 } catch (InstantiationException | IllegalAccessException e) {
48 e.printStackTrace();
49 }
50 for (Map.Entry<String, String> entry : map.entrySet()) {
51 try {
52 Field field = clazz.getDeclaredField(entry.getKey());
53 field.setAccessible(true);
54 field.set(comment, entry.getValue());
55 } catch (IllegalAccessException | NoSuchFieldException e) {
56 e.printStackTrace();
57 }
58 }
59 return comment;
60 }
工具方法
1 private long now() {
2 return System.currentTimeMillis() / 1000;
3 }
4
5 private String time() {
6 SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
7 return df.format(new Date());
8 }
实验
1 private static final int VOTE_SCORE = 432;
2
3 private static Song[] songs = new Song[5];
4
5 static {
6 for (int i = 0; i < songs.length; i++) {
7 songs[i] = new Song("1989" + i, "Taylor Swift" + i);
8 }
9 }
10
11 public static void main(String[] args) {
12 MyChapter01 chapter01 = new MyChapter01();
13
14 Jedis conn = new Jedis("localhost");
15 conn.select(10);
16
17 // for (Song song : songs) {
18 // chapter01.addSong(conn, song);
19 // }
20
21 // chapter01.addComment(conn, "6", "霉霉好棒");
22 // chapter01.addComment(conn, "6", "女神加油");
23
24 //少写一个点赞验证的set hhh
25 chapter01.good(conn, "6", "1");
26
27 List<Song> list = chapter01.song(conn);
28 for (Song song : list) {
29 System.out.println(song);
30 }
31 }
结果