一、Jedis,Redisson,Lettuce 三者的区别
共同点：都提供了基于 Redis 操作的 Java API，只是封装程度，具体实现稍有不同。
不同点：
-
1.1、Jedis
是 Redis 的 Java 实现的客户端。支持基本的数据类型如：String、Hash、List、Set、Sorted Set。
特点：使用阻塞的 I/O，方法调用同步，程序流需要等到 socket 处理完 I/O 才能执行，不支持异步操作。Jedis 客户端实例不是线程安全的，需要通过连接池来使用 Jedis。
-
1.1、Redisson
优点点：分布式锁，分布式集合，可通过 Redis 支持延迟队列。
-
1.3、 Lettuce
用于线程安全同步，异步和响应使用，支持集群，Sentinel，管道和编码器。
基于 Netty 框架的事件驱动的通信层，其方法调用是异步的。Lettuce 的 API 是线程安全的，所以可以操作单个 Lettuce 连接来完成各种操作。
二、Jedis
三、RedisTemplate
3.1、使用配置
maven 配置引入，（要加上版本号，这里是因为 Parent 已声明）
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency>
application-dev.yml
spring:
redis:
host: 192.168.1.140
port: 6379
password:
database: 15 # 指定redis的分库（共16个0到15）
3.2、使用示例
@Resource private StringRedisTemplate stringRedisTemplate; @Override public CustomersEntity findById(Integer id) { // 需要缓存 // 所有涉及的缓存都需要删除，或者更新 try { String toString = stringRedisTemplate.opsForHash().get(REDIS_CUSTOMERS_ONE, id + "").toString(); if (toString != null) { return JSONUtil.toBean(toString, CustomersEntity.class); } } catch (Exception e) { e.printStackTrace(); } // 缓存为空的时候，先查,然后缓存redis Optional<CustomersEntity> byId = customerRepo.findById(id); if (byId.isPresent()) { CustomersEntity customersEntity = byId.get(); try { stringRedisTemplate.opsForHash().put(REDIS_CUSTOMERS_ONE, id + "", JSONUtil.toJsonStr(customersEntity)); } catch (Exception e) { e.printStackTrace(); } return customersEntity; } return null; }
3.3、扩展
3.3.1、spring-boot-starter-data-redis 的依赖包
3.3.2、stringRedisTemplate API（部分展示）
opsForHash --> hash 操作
opsForList --> list 操作
opsForSet --> set 操作
opsForValue --> string 操作
opsForZSet --> Zset 操作
3.3.3 StringRedisTemplate 默认序列化机制
public class StringRedisTemplate extends RedisTemplate<String, String> { /** * Constructs a new <code>StringRedisTemplate</code> instance. {@link #setConnectionFactory(RedisConnectionFactory)} * and {@link #afterPropertiesSet()} still need to be called. */ public StringRedisTemplate() { RedisSerializer<String> stringSerializer = new StringRedisSerializer(); setKeySerializer(stringSerializer); setValueSerializer(stringSerializer); setHashKeySerializer(stringSerializer); setHashValueSerializer(stringSerializer); } }
四、RedissonClient 操作示例
4.1 基本配置
4.1.1、Maven pom 引入
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <dependency> <groupId>org.redisson</groupId> <artifactId>redisson</artifactId> <version>3.8.2</version> <optional>true</optional> </dependency> <dependency> <groupId>org.redisson</groupId> <artifactId>redisson-spring-boot-starter</artifactId> <version>LATEST</version> </dependency>
4.1.2、添加配置文件 Yaml 或者 json 格式
redisson-config.yml
# Redisson 配置
singleServerConfig:
address: "redis://192.168.1.140:6379"
password: null
clientName: null
database: 15 #选择使用哪个数据库0~15
idleConnectionTimeout: 10000
pingTimeout: 1000
connectTimeout: 10000
timeout: 3000
retryAttempts: 3
retryInterval: 1500
reconnectionTimeout: 3000
failedAttempts: 3
subscriptionsPerConnection: 5
subscriptionConnectionMinimumIdleSize: 1
subscriptionConnectionPoolSize: 50
connectionMinimumIdleSize: 32
connectionPoolSize: 64
dnsMonitoringInterval: 5000
#dnsMonitoring: false
threads: 0
nettyThreads: 0
codec:
class: "org.redisson.codec.JsonJacksonCodec"
transportMode: "NIO"
或者，配置 redisson-config.json
{ "singleServerConfig": { "idleConnectionTimeout": 10000, "pingTimeout": 1000, "connectTimeout": 10000, "timeout": 3000, "retryAttempts": 3, "retryInterval": 1500, "reconnectionTimeout": 3000, "failedAttempts": 3, "password": null, "subscriptionsPerConnection": 5, "clientName": null, "address": "redis://192.168.1.140:6379", "subscriptionConnectionMinimumIdleSize": 1, "subscriptionConnectionPoolSize": 50, "connectionMinimumIdleSize": 10, "connectionPoolSize": 64, "database": 0, "dnsMonitoring": false, "dnsMonitoringInterval": 5000 }, "threads": 0, "nettyThreads": 0, "codec": null, "useLinuxNativeEpoll": false }
4.1.3、读取配置
新建读取配置类
@Configuration public class RedissonConfig { @Bean public RedissonClient redisson() throws IOException { // 两种读取方式，Config.fromYAML 和 Config.fromJSON // Config config = Config.fromJSON(RedissonConfig.class.getClassLoader().getResource("redisson-config.json")); Config config = Config.fromYAML(RedissonConfig.class.getClassLoader().getResource("redisson-config.yml")); return Redisson.create(config); } }
或者，在 application.yml 中配置如下
spring:
redis:
redisson:
config: classpath:redisson-config.yaml
4.2 使用示例
@RestController @RequestMapping("/") public class TeController { @Autowired private RedissonClient redissonClient; static long i = 20; static long sum = 300; // ========================== String ======================= @GetMapping("/set/{key}") public String s1(@PathVariable String key) { // 设置字符串 RBucket<String> keyObj = redissonClient.getBucket(key); keyObj.set(key + "1-v1"); return key; } @GetMapping("/get/{key}") public String g1(@PathVariable String key) { // 设置字符串 RBucket<String> keyObj = redissonClient.getBucket(key); String s = keyObj.get(); return s; } // ========================== hash =======================-= @GetMapping("/hset/{key}") public String h1(@PathVariable String key) { Ur ur = new Ur(); ur.setId(MathUtil.randomLong(1,20)); ur.setName(key); // 存放 Hash RMap<String, Ur> ss = redissonClient.getMap("UR"); ss.put(ur.getId().toString(), ur); return ur.toString(); } @GetMapping("/hget/{id}") public String h2(@PathVariable String id) { // hash 查询 RMap<String, Ur> ss = redissonClient.getMap("UR"); Ur ur = ss.get(id); return ur.toString(); } // 查询所有的 keys @GetMapping("/all") public String all(){ RKeys keys = redissonClient.getKeys(); Iterable<String> keys1 = keys.getKeys(); keys1.forEach(System.out::println); return keys.toString(); } // ================== ==============读写锁测试 ============================= @GetMapping("/rw/set/{key}") public void rw_set(){ // RedissonLock. RBucket<String> ls_count = redissonClient.getBucket("LS_COUNT"); ls_count.set("300",360000000l, TimeUnit.SECONDS); } // 减法运算 @GetMapping("/jf") public void jf(){ String key = "S_COUNT"; // RAtomicLong atomicLong = redissonClient.getAtomicLong(key); // atomicLong.set(sum); // long l = atomicLong.decrementAndGet(); // System.out.println(l); RAtomicLong atomicLong = redissonClient.getAtomicLong(key); if (!atomicLong.isExists()) { atomicLong.set(300l); } while (i == 0) { if (atomicLong.get() > 0) { long l = atomicLong.getAndDecrement(); try { Thread.sleep(1000l); } catch (InterruptedException e) { e.printStackTrace(); } i --; System.out.println(Thread.currentThread().getName() + "->" + i + "->" + l); } } } @GetMapping("/rw/get") public String rw_get(){ String key = "S_COUNT"; Runnable r = new Runnable() { @Override public void run() { RAtomicLong atomicLong = redissonClient.getAtomicLong(key); if (!atomicLong.isExists()) { atomicLong.set(300l); } if (atomicLong.get() > 0) { long l = atomicLong.getAndDecrement(); i --; System.out.println(Thread.currentThread().getName() + "->" + i + "->" + l); } } }; while (i != 0) { new Thread(r).start(); // new Thread(r).run(); // new Thread(r).run(); // new Thread(r).run(); // new Thread(r).run(); } RBucket<String> bucket = redissonClient.getBucket(key); String s = bucket.get(); System.out.println("================线程已结束================================" + s); return s; } }
4.3 扩展
4.3.1 丰富的 jar 支持，尤其是对 Netty NIO 框架
4.3.2 丰富的配置机制选择，这里是详细的配置说明
关于序列化机制中，就有很多
4.3.3 API 支持（部分展示），具体的 Redis --> RedissonClient , 可查看这里
4.3.4 轻便的丰富的锁机制的实现
4.3.4.1 Lock
4.3.4.2 Fair Lock
4.3.4.3 MultiLock
4.3.4.4 RedLock
4.3.4.5 ReadWriteLock
4.3.4.6 Semaphore
4.3.4.7 PermitExpirableSemaphore
4.3.4.8 CountDownLatch
五、基于注解实现的 Redis 缓存
5.1 Maven 和 YML 配置
参考 RedisTemplate 配置
另外，还需要额外的配置类
// todo 定义序列化，解决乱码问题
@EnableCaching
@Configuration
@ConfigurationProperties(prefix = "spring.cache.redis")
public class RedisCacheConfig {
private Duration timeToLive = Duration.ZERO;
public void setTimeToLive(Duration timeToLive) {
this.timeToLive = timeToLive;
}
@Bean
public CacheManager cacheManager(RedisConnectionFactory factory) {
RedisSerializer<String> redisSerializer = new StringRedisSerializer();
Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
// 解决查询缓存转换异常的问题
ObjectMapper om = new ObjectMapper();
om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jackson2JsonRedisSerializer.setObjectMapper(om);
// 配置序列化（解决乱码的问题）
RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
.entryTtl(timeToLive)
.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer))
.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer))
.disableCachingNullValues();
RedisCacheManager cacheManager = RedisCacheManager.builder(factory)
.cacheDefaults(config)
.build();
return cacheManager;
}
}
5.2 使用示例
@Transactional
@Service
public class ReImpl implements RedisService {
@Resource
private CustomerRepo customerRepo;
@Resource
private StringRedisTemplate stringRedisTemplate;
public static final String REDIS_CUSTOMERS_ONE = "Customers";
public static final String REDIS_CUSTOMERS_ALL = "allList";
// =====================================================================使用Spring cahce 注解方式实现缓存
// ==================================单个操作
@Override
@Cacheable(value = "cache:customer", unless = "null == #result",key = "#id")
public CustomersEntity cacheOne(Integer id) {
final Optional<CustomersEntity> byId = customerRepo.findById(id);
return byId.isPresent() ? byId.get() : null;
}
@Override
@Cacheable(value = "cache:customer", unless = "null == #result", key = "#id")
public CustomersEntity cacheOne2(Integer id) {
final Optional<CustomersEntity> byId = customerRepo.findById(id);
return byId.isPresent() ? byId.get() : null;
}
// todo 自定义redis缓存的key,
@Override
@Cacheable(value = "cache:customer", unless = "null == #result", key = "#root.methodName + '.' + #id")
public CustomersEntity cacheOne3(Integer id) {
final Optional<CustomersEntity> byId = customerRepo.findById(id);
return byId.isPresent() ? byId.get() : null;
}
// todo 这里缓存到redis，还有响应页面是String（加了很多转义符\,），不是Json格式
@Override
@Cacheable(value = "cache:customer", unless = "null == #result", key = "#root.methodName + '.' + #id")
public String cacheOne4(Integer id) {
final Optional<CustomersEntity> byId = customerRepo.findById(id);
return byId.map(JSONUtil::toJsonStr).orElse(null);
}
// todo 缓存json，不乱码已处理好,调整序列化和反序列化
@Override
@Cacheable(value = "cache:customer", unless = "null == #result", key = "#root.methodName + '.' + #id")
public CustomersEntity cacheOne5(Integer id) {
Optional<CustomersEntity> byId = customerRepo.findById(id);
return byId.filter(obj -> !StrUtil.isBlankIfStr(obj)).orElse(null);
}
// ==================================删除缓存
@Override
@CacheEvict(value = "cache:customer", key = "'cacheOne5' + '.' + #id")
public Object del(Integer id) {
// 删除缓存后的逻辑
return null;
}
@Override
@CacheEvict(value = "cache:customer",allEntries = true)
public void del() {
}
@CacheEvict(value = "cache:all",allEntries = true)
public void delall() {
}
// ==================List操作
@Override
@Cacheable(value = "cache:all")
public List<CustomersEntity> cacheList() {
List<CustomersEntity> all = customerRepo.findAll();
return all;
}
// todo 先查询缓存，再校验是否一致，然后更新操作，比较实用，要清楚缓存的数据格式（明确业务和缓存模型数据）
@Override
@CachePut(value = "cache:all",unless = "null == #result",key = "#root.methodName")
public List<CustomersEntity> cacheList2() {
List<CustomersEntity> all = customerRepo.findAll();
return all;
}
}
5.3 扩展
基于 spring 缓存实现
