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摘要: 原创出处 blog.csdn.net/qq_42105629/article/details/102589319 「Tonels」欢迎转载,保留摘要,谢谢!


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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。

1.2、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、RedisTemplate

2.1、使用配置

maven配置引入,(要加上版本号,我这里是因为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)

2.2、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;
}

2.3、扩展

2.3.1、spring-boot-starter-data-redis的依赖包

图片

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

图片

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);
}
}

三、RedissonClient 操作示例

3.1 基本配置

3.1.1、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>

3.1.2、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
}

3.1.3、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

3.2 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;
}

}

3.3 扩展

3.3.1 丰富的jar支持,尤其是对 Netty NIO框架

3.3.2 丰富的配置机制选择,这里是详细的配置说明

https://github.com/redisson/redisson/wiki/2.-Configuration

关于序列化机制中,就有很多

图片

图片

3.3.3 API支持(部分展示),具体的 Redis –> RedissonClient ,可查看这里

https://github.com/redisson/redisson/wiki/11.-Redis-commands-mapping

图片

3.3.4 轻便的丰富的锁机制的实现

  • Lock
  • Fair Lock
  • MultiLock
  • RedLock
  • ReadWriteLock
  • Semaphore
  • PermitExpirableSemaphore
  • CountDownLatch

四、基于注解实现的Redis缓存

4.1 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;
}

}

4.2 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;
}

}

4.3 扩展

基于spring缓存实现

图片

文章目录
  1. 1. 一、Jedis,Redisson,Lettuce三者的区别
    1. 1.1. 1.1、Jedis
    2. 1.2. 1.2、Redisson
    3. 1.3. 1.3、 Lettuce
  2. 2. 二、RedisTemplate
    1. 2.1. 2.1、使用配置
    2. 2.2. 2.2、使用示例
    3. 2.3. 2.3、扩展
      1. 2.3.0.1. 2.3.1、spring-boot-starter-data-redis的依赖包
      2. 2.3.0.2. 3.3.2、stringRedisTemplate API(部分展示)
      3. 2.3.0.3. 3.3.3 StringRedisTemplate默认序列化机制
  • 3. 三、RedissonClient 操作示例
    1. 3.1. 3.1 基本配置
      1. 3.1.0.1. 3.1.1、Maven pom 引入
      2. 3.1.0.2. 3.1.2、添加配置文件Yaml或者json格式
      3. 3.1.0.3. 3.1.3、读取配置
  • 3.2. 3.2 使用示例
  • 3.3. 3.3 扩展
  • 4. 四、基于注解实现的Redis缓存
    1. 4.1. 4.1 Maven 和 YML配置
    2. 4.2. 4.2 使用示例
    3. 4.3. 4.3 扩展