SpringBoot_ integrated Redis

Spring boot Redis integration step is as follows:

1, arranged in pom.xml related dependent jar:

<! - Load spring boot redis bag ->
<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

2, the configuration information in connection redis Springboot core configuration file application.properties in:

spring.redis.host=192.168.230.128
spring.redis.port=6379
spring.redis.password=123456

3, the configuration of the above steps, Spring boot will automatically configure RedisTemplate, injection redisTemplate redis need to operate in the class of:

Redis entity class must implement the operation sequence of the interface

 

 

 

After the success of key discovery into redis have some special encoding format, readability is not high

 

 

 

 

 

 

 

 

spring boot injected redisTemplate class to help us, which can only write the generic <String, String>, <Object, Object>

In the case of high concurrency, this method may be problematic: may not be cached, are taking to the database query, to increase pressure on the database server.

In action in the simulated multi-threaded method to access the sevice

@Autowired
 private TClassService tClassService;

@RequestMapping("index.do")
public @ResponseBody Object list(){
    //模拟高并发
    Runnable runnable = new Runnable() {
        @Override
        public void run() {
            tClassService.list ();
        }
    };
    ExecutorService executorService = Executors.newFixedThreadPool(10);
    for (int i=0;i<100;i++){
        executorService.submit(runnable);
    }
    Return tClassService.list ();
}

Modify service method prompts

public List<TClass> list() {
    RedisSerializer redisSerializer = new StringRedisSerializer();
    redisTemplate.setKeySerializer(redisSerializer);

    // First cache query 
    List <TClass> List = (List <TClass>) redisTemplate.opsForValue () GET ( "data.class." );
     // if there is no data in the cache, to fetch data from the database 
    IF (List == null ) {
        System.out.println ( "database query" );
         // get data from the database query results into the cache after 
        List = classMapper.list ();
        redisTemplate.opsForValue().set("data.class",list);
    }else {
        System.out.println ( "query caching" );
    }
    return list;
}

Start, test results, many of which are issued in the database search, rather than the query cache

 

 

 Principle: simultaneous multi-threading into the method

 

 

 A solution: a synchronization method

Folder on the method synchronized keyword, synchronization method, efficiency is too low

Two solutions: a synchronization code blocks

public List<TClass> list() {
    RedisSerializer redisSerializer = new StringRedisSerializer();
    redisTemplate.setKeySerializer(redisSerializer);

    // First cache query 
    List <TClass> List = (List <TClass>) redisTemplate.opsForValue () GET ( "data.class." );
     IF (List == null ) { // If found, not the lock, to improve efficiency 
        the synchronized ( the this ) {
            List = (List <TClass>) redisTemplate.opsForValue () GET ( "data.class." );
             // if there is no data in the cache, to fetch data from the database 
            IF (List == null ) {
                System.out.println ( "database query" );
                 // get data from the database query results into the cache after 
                List = classMapper.list ();
                redisTemplate.opsForValue().set("data.class",list);
            }else {
                System.out.println ( "query caching" );
            }
        }
    }else{
        System.out.println ( "query caching" );
    }
    return list;
}

The test results, only the first query the database, the rest are query cache

 

 Sentinel redis cluster configuration mode:

#redis cluster configuration mode Sentinel
spring.redis.password=redis
spring.redis.sentinel.master=mymaster
spring.redis.sentinel.nodes=192.168.179.128:26380,192.168.179.128:26382,192.168.179.128:26384