2020-12-18

<dependency>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-cache</artifactId>

<version>${boot.version}</version>

</dependency>

spring:

      #cache:

        #缓存名称

        #cache-names: guavaDemo

        #缓存最大数量500条, 缓存失效时间 6个小时

        #guava.spec: maximumSize=500,expireAfterWrite=360m

      # REDIS (RedisProperties)  

      redis :

        host : localhost # server host  

        port : 6379 # connection port  

        password : 123

        pool.max-idle : 8 # pool settings ...  

        pool.min-idle : 1

        pool.max-active : 8  

        pool.max-wait : -1  

package com.ding.data.config;


import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.concurrent.TimeUnit;


import javax.annotation.Resource;


import org.springframework.boot.ApplicationArguments;

import org.springframework.boot.ApplicationRunner;

import org.springframework.cache.CacheManager;

import org.springframework.cache.guava.GuavaCacheManager;

import org.springframework.cache.support.CompositeCacheManager;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.context.annotation.Primary;

import org.springframework.data.redis.cache.RedisCacheManager;

import org.springframework.data.redis.core.RedisTemplate;

import org.springframework.data.redis.serializer.StringRedisSerializer;


import com.google.common.cache.CacheBuilder;

import com.google.common.collect.Lists;


@Configuration

public class CacheConfig implements ApplicationRunner {

@Resource

private List<CacheManager> cacheManagers;


public void run(ApplicationArguments args) throws Exception {

System.out.println("CacheManager大小为=========" + cacheManagers.size());

System.out.println("=================================================");

for(CacheManager c:cacheManagers){

System.out.println(c.getCacheNames());

}

}


@Bean(name = "redisCacheManager")

public RedisCacheManager redisCacheManager(

RedisTemplate<Object, Object> redisTemplate) {

redisTemplate.setKeySerializer(new StringRedisSerializer());

RedisCacheManager redisCacheManager = new RedisCacheManager(

redisTemplate);

redisCacheManager.setCacheNames(Arrays.asList("redisDemo"));

redisCacheManager.setUsePrefix(true);

return redisCacheManager;

}


@Bean(name = "guavaCacheManager")

public GuavaCacheManager getGuavaCacheManager() {

GuavaCacheManager guavaCacheManager = new GuavaCacheManager();

guavaCacheManager.setCacheBuilder(CacheBuilder.newBuilder()

.expireAfterWrite(3600, TimeUnit.SECONDS).maximumSize(1000));

ArrayList<String> guavaCacheNames = Lists.newArrayList();

guavaCacheNames.add("guavaDemo");

guavaCacheManager.setCacheNames(guavaCacheNames);

return guavaCacheManager;

}


@Bean(name = "cacheManager")

@Primary

public CompositeCacheManager cacheManager(

RedisCacheManager redisCacheManager,

GuavaCacheManager guavaCacheManager) {

CompositeCacheManager cacheManager = new CompositeCacheManager(

redisCacheManager, guavaCacheManager);

return cacheManager;

}

}

Punto 4-caché de guayaba

package com.ding.data.cache;


import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.HashMap;

import java.util.Map;


import javax.annotation.PostConstruct;


import org.springframework.cache.annotation.CacheEvict;

import org.springframework.cache.annotation.CachePut;

import org.springframework.cache.annotation.Cacheable;

import org.springframework.stereotype.Service;


@Service

//@CacheConfig(cacheManager = "guavaCacheManager")

public class GuavaDataCache {


private Map<Long, String> dataMap = new HashMap<Long, String>();


/**

 * 初始化

 */

@PostConstruct

public void init() {

dataMap.put(1L, "张三");

dataMap.put(2L, "李四");

dataMap.put(3L, "王五");

}


/**

 * 查询

 * 如果数据没有缓存,那么从dataMap里面获取,如果缓存了,

 * 那么从guavaDemo里面获取

 * 并且将缓存的数据存入到 guavaDemo里面

 * 其中key 为 #id+dataMap

 */

@Cacheable(value="guavaDemo" ,key="#id + 'dataMap'")

public String query(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.format(new Date()) + " : query id is " + id);

return dataMap.get(id);

}


/**

 * 插入 或者更新

 * 插入或更新数据到dataMap中

 * 并且缓存到 guavaDemo中

 * 如果存在了那么更新缓存中的值

 * 其中key 为 #id+dataMap

 */

@CachePut(value="guavaDemo" ,key="#id + 'dataMap'")

public String put(Long id, String value) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.format(new Date()) + " : add data ,id is "+ id);

dataMap.put(id, value);

// data persistence

return value;

}


/**

 * 删除

 * 删除dataMap里面的数据

 * 并且删除缓存guavaDemo中的数据

 * 其中key 为 #id+dataMap

 */

@CacheEvict(value="guavaDemo" , key="#id + 'dataMap'")

public void remove(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.format(new Date()) + " : remove id is "+ id + " data");

dataMap.remove(id);

// data remove  

}


}

Punto 5-redis caché

package com.ding.data.cache;


import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.HashMap;

import java.util.Map;


import javax.annotation.PostConstruct;


import org.springframework.cache.annotation.CacheEvict;

import org.springframework.cache.annotation.CachePut;

import org.springframework.cache.annotation.Cacheable;

import org.springframework.stereotype.Service;


@Service

//@CacheConfig(cacheManager = "redisCacheManager")

public class RedisDataCache {


private Map<Long, String> dataMap = new HashMap<Long, String>();


/**

 * 初始化

 */

@PostConstruct

public void init() {

dataMap.put(1L, "111");

dataMap.put(2L, "222");

dataMap.put(3L, "333");

}


/**

 * 查询

 * 如果数据没有缓存,那么从dataMap里面获取,如果缓存了,

 * 那么从guavaDemo里面获取

 * 并且将缓存的数据存入到 guavaDemo里面

 * 其中key 为 #id+dataMap

 */

@Cacheable(value="redisDemo" ,key="#id + 'dataMap'")

public String query(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.format(new Date()) + " : query id is " + id);

return dataMap.get(id);

}


/**

 * 插入 或者更新

 * 插入或更新数据到dataMap中

 * 并且缓存到 guavaDemo中

 * 如果存在了那么更新缓存中的值

 * 其中key 为 #id+dataMap

 */

@CachePut(value="redisDemo" ,key="#id + 'dataMap'")

public String put(Long id, String value) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.format(new Date()) + " : add data ,id is "+ id);

dataMap.put(id, value);

// data persistence

return value;

}


/**

 * 删除

 * 删除dataMap里面的数据

 * 并且删除缓存guavaDemo中的数据

 * 其中key 为 #id+dataMap

 */

@CacheEvict(value="redisDemo" , key="#id + 'dataMap'")

public void remove(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.format(new Date()) + " : remove id is "+ id + " data");

dataMap.remove(id);

// data remove  

}


}

Punto 6-llamada

package com.ding.data;


import java.text.SimpleDateFormat;

import java.util.Date;


import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.cache.annotation.EnableCaching;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;


import com.ding.data.cache.GuavaDataCache;

import com.ding.data.cache.RedisDataCache;


/**

 * 是Spring Boot项目的核心注解,主要是开启自动配置

 */

@SpringBootApplication

// same as @Configuration @EnableAutoConfiguration @ComponentScan

@RestController

// 开启缓存

@EnableCaching

public class App {


@Autowired

private GuavaDataCache dataCache;


@Autowired

private RedisDataCache rdataCache;


public static void main(String[] args) {

SpringApplication.run(App.class, args);

}


@RequestMapping("/put")

public String put(Long id, String value) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

return sdf.format(new Date()) + " : value is "

+ dataCache.put(id, value);

}


@RequestMapping("/get")

public String query(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

return sdf.format(new Date()) + " : value is " + dataCache.query(id);

}


@RequestMapping("/remove")

public String remove(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

dataCache.remove(id);

return sdf.format(new Date()) + " : success ";

}


@RequestMapping("/putr")

public String putr(Long id, String value) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

return sdf.format(new Date()) + " : value is "

+ rdataCache.put(id, value);

}


@RequestMapping("/getr")

public String queryr(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

return sdf.format(new Date()) + " : value is " + rdataCache.query(id);

}


@RequestMapping("/remover")

public String remover(Long id) {

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

rdataCache.remove(id);

return sdf.format(new Date()) + " : success ";

}


}

Prueba 1-si hay escritura en redis-sí

Acceso a RedisCache

acceso

http: // localhost: 8080 / getr? id = 1

Ver el servidor Redis, de la siguiente manera

visible

/ getr? id = 1

Cuando este enlace regresa, los datos se escriben en el servidor de Redis.

Prueba 2: acceso a la caché de guayaba

acceso

http: // localhost: 8080 / get? id = 1

Luego llame

http: // localhost: 8080 / put? id = 1 & value = 777777

Verifique el valor en Redis, no hay cambios. Muestra que el caché de redis y el caché de guayaba no interfieren entre sí, y se accede a ellos correctamente como se esperaba. ¿Por qué dices eso? Como probé otras configuraciones antes, resultó que el caché estaba dañado, pero ahora es normal, lo que indica que los archivos de configuración actuales y la información de configuración relacionada están escritos correctamente.

★ Explicación del punto 3

Imprimir durante el inicio del proyecto

Lo siguiente se imprime durante el inicio del proyecto. El uso específico de la interfaz ApplicationRunner puede ser Baidu. No es necesario implementar la interfaz ApplicationRunner, aquí es para imprimir y mostrar el CacheManager al inicio.

Se puede ver en la figura  @Bean  anotado que se agregan tres CachaManager en los cacheManagers.

CompositeCacheManager

Spring Cache puede usar el nombre de la caché (atributo cacheNames) en CacheManager para distinguir la caché. Spring Cache proporciona CompositeCacheManager para proxy todos los CacheManagers. Recorra todos los CacheManagers de acuerdo con el cacheName especificado para encontrar el caché correspondiente.