feat: add junit test for java code

添加 Java 代码及单元测试

README.md

@@ -24,8 +24,6 @@
 | 2 | Redis 使用手册[2019] | 黄健宏 | 帮助读者学习如何将 Redis 应用到实际开发中，内容涵盖最新的 Redis 5。 |
 
 
-学习下面知识之前，先来[感受一波 Redis 面试连环炮](/docs/redis-interview.md)。
-
 ## Redis 数据结构与应用
 
 ### [String 字符串](/docs/redis-string-introduction.md)

java/build.gradle

@@ -13,4 +13,6 @@ repositories {
 dependencies {
  testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-api', version: '5.5.2'
  compile group: 'redis.clients', name: 'jedis', version: '3.1.0'
+ compile group: 'commons-codec', name: 'commons-codec', version: '1.13'
+
 }

java/src/main/java/LoginSession.java

@@ -0,0 +1,102 @@
+import org.apache.commons.codec.binary.Hex;
+import redis.clients.jedis.Jedis;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.time.Instant;
+import java.util.Random;
+
+
+public class LoginSession {
+
+ private final String SESSION_TOKEN_KEY = "SESSION:TOKEN";
+ private final String SESSION_EXPIRE_TS_KEY = "SESSION:EXPIRE";
+
+ private final String SESSION_NOT_LOGIN = "SESSION_NOT_LOGIN";
+ private final String SESSION_EXPIRE = "SESSION_EXPIRE";
+ private final String SESSION_TOKEN_CORRECT = "SESSION_TOKEN_CORRECT";
+ private final String SESSION_TOKEN_INCORRECT = "SESSION_TOKEN_INCORRECT";
+
+ private Jedis client;
+ private String userId;
+
+ public LoginSession(Jedis client, String userId) {
+ this.client = client;
+ this.userId = userId;
+ }
+
+ /**
+ * 生成随机token
+ *
+ * @return token
+ */
+ private String generateToken() {
+ byte[] b = new byte[256];
+ new Random().nextBytes(b);
+
+ MessageDigest messageDigest;
+
+ String sessionToken = "";
+ try {
+ messageDigest = MessageDigest.getInstance("SHA-256");
+ byte[] hash = messageDigest.digest(b);
+ sessionToken = Hex.encodeHexString(hash);
+ } catch (NoSuchAlgorithmException e) {
+ e.printStackTrace();
+ }
+ return sessionToken;
+ }
+
+ /**
+ * 创建会话，并返回token
+ *
+ * @param timeout 过期时长
+ * @return token
+ */
+ public String create(int timeout) {
+ String token = generateToken();
+ long expireTime = Instant.now().getEpochSecond() + timeout;
+ client.hset(SESSION_TOKEN_KEY, userId, token);
+ client.hset(SESSION_EXPIRE_TS_KEY, userId, String.valueOf(expireTime));
+ return token;
+ }
+
+ public String create() {
+ // 设置默认过期时长
+ int defaultTimeout = 30 * 24 * 3600;
+ return create(defaultTimeout);
+ }
+
+ /**
+ * 校验token
+ *
+ * @param token 输入的token
+ * @return 校验结果
+ */
+ public String validate(String token) {
+ String sessionToken = client.hget(SESSION_TOKEN_KEY, userId);
+ String expireTimeStr = client.hget(SESSION_EXPIRE_TS_KEY, userId);
+
+ if (sessionToken == null || expireTimeStr == null) {
+ return SESSION_NOT_LOGIN;
+ }
+
+ Long expireTime = Long.parseLong(expireTimeStr);
+ if (Instant.now().getEpochSecond() > expireTime) {
+ return SESSION_EXPIRE;
+ }
+
+ if (sessionToken.equals(token)) {
+ return SESSION_TOKEN_CORRECT;
+ }
+ return SESSION_TOKEN_INCORRECT;
+ }
+
+ /**
+ * 销毁会话
+ */
+ public void destroy() {
+ client.hdel(SESSION_TOKEN_KEY, userId);
+ client.hdel(SESSION_EXPIRE_TS_KEY, userId);
+ }
+}

java/src/main/java/Paginate.java

@@ -0,0 +1,45 @@
+import redis.clients.jedis.Jedis;
+
+import java.util.List;
+
+public class Paginate {
+
+ private Jedis client;
+ private String key;
+
+ public Paginate(Jedis client, String key) {
+ this.client = client;
+ this.key = key;
+ }
+
+ /**
+ * 添加元素到分页列表中
+ *
+ * @param item 元素
+ */
+ public void add(String item) {
+ client.lpush(key, item);
+ }
+
+ /**
+ * 根据页码取出指定数量的元素
+ *
+ * @param page 页码
+ * @param pageSize 数量
+ * @return 元素列表
+ */
+ public List<String> getPage(int page, int pageSize) {
+ long start = (page - 1) * pageSize;
+ long end = page * pageSize - 1;
+ return client.lrange(key, start, end);
+ }
+
+ /**
+ * 获取列表的元素数量
+ *
+ * @return 总数
+ */
+ public Long getTotalCount() {
+ return client.llen(key);
+ }
+}

java/src/main/java/Ranking.java

@@ -0,0 +1,67 @@
+import redis.clients.jedis.Jedis;
+import redis.clients.jedis.Tuple;
+
+import java.util.Calendar;
+import java.util.Set;
+
+/**
+ * @author bingoyang
+ * @date 2019/9/7
+ */
+public class Ranking {
+ private Jedis client = new Jedis();
+ private Calendar calendar = Calendar.getInstance();
+
+ public Ranking() {
+ client.flushAll();
+ calendar.setFirstDayOfWeek(Calendar.MONDAY);
+ }
+
+ private String getDayRankKey() {
+ return String.format("rank:day:%s%s%s", calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH));
+ }
+
+ private String getWeekRankKey() {
+ return String.format("rank:week:%s%s", calendar.get(Calendar.YEAR), calendar.get(Calendar.WEEK_OF_YEAR));
+ }
+
+ private String getMonthRankKey() {
+ return String.format("rank:month:%s%s", calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH));
+ }
+
+ public void incr(String user, double score) {
+ client.zincrby(getDayRankKey(), score, user);
+ client.zincrby(getWeekRankKey(), score, user);
+ client.zincrby(getMonthRankKey(), score, user);
+ }
+
+ /**
+ * 获取日榜单topN
+ *
+ * @param n 前n位
+ * @return 结果集合
+ */
+ public Set<Tuple> getTodayTopNWithScores(long n) {
+ return client.zrevrangeWithScores(getDayRankKey(), 0, n - 1);
+ }
+
+ /**
+ * 获取周榜单topN
+ *
+ * @param n 前n位
+ * @return 结果集合
+ */
+ public Set<Tuple> getWeekTopNWithScores(long n) {
+ return client.zrevrangeWithScores(getWeekRankKey(), 0, n - 1);
+ }
+
+ /**
+ * 获取月榜单topN
+ *
+ * @param n 前n位
+ * @return 结果集合
+ */
+ public Set<Tuple> getMonthTopNWithScores(long n) {
+ return client.zrevrangeWithScores(getMonthRankKey(), 0, n - 1);
+ }
+}

java/src/main/java/URLShorten.java

@@ -0,0 +1,55 @@
+import redis.clients.jedis.Jedis;
+
+public class URLShorten {
+ private Jedis client;
+
+ private final String URL_HASH_SHORT_SOURCE_KEY = "url_hash:short_source";
+ private final String ID_COUNTER = "short_url:id_counter";
+
+ /**
+ * 将10进制数转换为36进制字符串
+ *
+ * @param number 10进制数
+ * @return 36进制字符串
+ */
+ private String base10ToBase36(long number) {
+ String alphabets = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+ char[] chars = alphabets.toCharArray();
+ StringBuilder result = new StringBuilder();
+ while (number != 0) {
+ int i = (int) number % 36;
+ number /= 36;
+ result.insert(0, chars[i]);
+ }
+ return result.toString();
+ }
+
+ public URLShorten(Jedis client) {
+ this.client = client;
+ // 设置初始ID值，保留1-5位的短码，从6位的短码开始生成
+ this.client.set(ID_COUNTER, String.valueOf((long) Math.pow(36, 5) - 1));
+ }
+
+ /**
+ * 对源网址进行缩短，返回短网址ID
+ *
+ * @param sourceUrl 源网址
+ * @return 短网址ID
+ */
+ public String shorten(String sourceUrl) {
+ long newId = client.incr(ID_COUNTER);
+ String shortId = base10ToBase36(newId);
+ client.hset(URL_HASH_SHORT_SOURCE_KEY, shortId, sourceUrl);
+ return shortId;
+ }
+
+ /**
+ * 根据短网址ID，返回对应的源网址
+ *
+ * @param shortId 短网址ID
+ * @return 源网址
+ */
+ public String restore(String shortId) {
+ return client.hget(URL_HASH_SHORT_SOURCE_KEY, shortId);
+ }
+}

java/src/test/java/DistributedLockTest.java

@@ -9,7 +9,7 @@
 public class DistributedLockTest {
 
  @Test
- public void test() throws InterruptedException {
+ public void testDistributedLock() throws InterruptedException {
  Jedis jedis = new Jedis();
  jedis.flushAll();
 

java/src/test/java/LoginSessionTest.java

@@ -0,0 +1,26 @@
+import org.junit.jupiter.api.Test;
+import redis.clients.jedis.Jedis;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class LoginSessionTest {
+
+ @Test
+ public void testLoginSession() {
+ Jedis client = new Jedis();
+ client.flushAll();
+ LoginSession session = new LoginSession(client, "bingo");
+
+ String token = session.create();
+
+ String res = session.validate("this is a wrong token");
+ assertEquals( "SESSION_TOKEN_INCORRECT", res);
+
+ res = session.validate(token);
+ assertEquals("SESSION_TOKEN_CORRECT", res);
+
+ session.destroy();
+ res = session.validate(token);
+ assertEquals("SESSION_NOT_LOGIN", res);
+ }
+}

java/src/test/java/PaginateTest.java

@@ -0,0 +1,36 @@
+import org.junit.jupiter.api.Test;
+import redis.clients.jedis.Jedis;
+
+import java.util.Arrays;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class PaginateTest {
+
+ @Test
+ public void testPaginate() {
+ Jedis client = new Jedis();
+ client.flushAll();
+
+ Paginate topics = new Paginate(client, "user-topics");
+ for (int i = 0; i < 24; ++i) {
+ topics.add(i + "");
+ }
+
+ // 取总数
+ assertEquals(24, topics.getTotalCount());
+
+ // 以每页5条数据的方式取出第1页数据
+ assertEquals(Arrays.asList("23", "22", "21", "20", "19"),
+ topics.getPage(1, 5));
+
+ // 以每页10条数据的方式取出第1页数据
+ assertEquals(Arrays.asList("23", "22", "21", "20", "19", "18", "17", "16", "15", "14"),
+ topics.getPage(1, 10));
+
+ // 以每页5条数据的方式取出第5页数据
+ assertEquals(Arrays.asList("3", "2", "1", "0"),
+ topics.getPage(5, 5));
+
+ }
+}

java/src/test/java/RankingTest.java

@@ -0,0 +1,31 @@
+import org.junit.jupiter.api.Test;
+import redis.clients.jedis.Tuple;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+
+public class RankingTest {
+
+ @Test
+ public void testRanking() {
+ Ranking ranking = new Ranking();
+
+ ranking.incr("bingo", 5);
+ ranking.incr("iris", 3);
+ ranking.incr("lily", 4);
+ ranking.incr("helen", 6);
+
+ Set<Tuple> expectResult = new HashSet<Tuple>() {{
+ add(new Tuple("helen", 6.0));
+ add(new Tuple("bingo", 5.0));
+ }};
+ assertEquals(expectResult, ranking.getTodayTopNWithScores(2));
+ assertEquals(expectResult, ranking.getWeekTopNWithScores(2));
+
+ expectResult.add(new Tuple("lily", 4.0));
+ assertEquals(expectResult, ranking.getMonthTopNWithScores(3));
+ }
+}