學了springcloud如何操作資料庫進行增删改查,又學了springcloud如何操作reids把資料存儲到redis。今天結合資料庫操作和reids操作,來看看如何使用SpringCache。SpringCache提供了基于注解的緩存配置方法。它本質上不是一個具體的緩存實作方案(例如EHCache),而是一個對緩存使用的抽象和封裝,通過在已有代碼中打上幾個預定義的注釋,就可以實作希望達到的緩存效果。SpringCache支援跟第三方緩存例如EHCache、Redis內建;另外也提供了開箱即用的預設實作,可以直接拿來使用。SpringCache支援使用SpEL(Spring ExpressionLanguage)來定義緩存的key和各種condition,是以具備相當的靈活性,并可以支援非常複雜的語義。
1、建立項目sc-redis-cache,對用的pom.xml檔案如下
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>spring-cloud</groupId>
<artifactId>sc-redis-cache</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>sc-redis-cache</name>
<url>http://maven.apache.org</url>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
</parent>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Finchley.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-pool2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-cache</artifactId>
</dependency>
<dependency>
<groupId>com.zaxxer</groupId>
<artifactId>HikariCP</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>6.0.3</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
</project>
2、建立springboot啟動類RedisCacheApplication.java
package sc.redis.cache;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import
org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;
/**
* 更多資源關注公衆号: java樂園
*
* @author Administrator
*
*/
@SpringBootApplication
@EnableCaching // 啟動緩存
@MapperScan(basePackages="sc.redis.cache.dao")
public class RedisCacheApplication {
public static void main(String[] args) {
SpringApplication.run(RedisCacheApplication.class,args);
}
}
備注:@MapperScan(basePackages="sc.redis.cache.dao")該注解的basePackages一定是DAO所在包最終報名。
如果寫成@MapperScan(basePackages="sc.redis.cache")這樣在測試中将報錯:
3、建立配置檔案application.yml
server:
port: 9003
spring:
application:
name: sc-redis-cache
datasource:
driverClassName: com.mysql.jdbc.Driver
url:jdbc:mysql://localhost:3306/sc?serverTimezone=UTC&useUnicode=true&characterEncoding=UTF-8
username:root
password: root
type: com.zaxxer.hikari.HikariDataSource
hikari:
minimum-idle: 5
maximum-pool-size: 15
auto-commit: true
idle-timeout: 30000
pool-name: DatebookHikariCP
max-lifetime: 1800000
connection-timeout: 30000
connection-test-query: SELECT 1
cache:
type: REDIS
redis:
timeToLive: 200000 #緩存逾時時間ms
cache-null-values: false #是否緩存空值
redis:
host: 127.0.0.1
password:
port: 6379
timeout: 10000 # 連接配接逾時時間(毫秒)
database: 0 # Redis預設情況下有16個分片,這裡配置具體使用的分片,預設是0
lettuce:
pool:
max-active: 8 # 連接配接池最大連接配接數(使用負值表示沒有限制)預設 8
max-wait: -1 # 連接配接池最大阻塞等待時間(使用負值表示沒有限制)預設 -1
max-idle: 8 # 連接配接池中的最大空閑連接配接預設 8
min-idle:0 # 連接配接池中的最小空閑連接配接預設 0
logging:
level:
sc.redis.cache.dao: debug
備注:配置檔案中有連接配接資料庫的配置資訊和連接配接redis的配置資訊,同時配置了列印sql語句的日志級别
4、建立自定義reids序列化方式RedisCacheSerializeConfiguration.java類
package sc.redis.cache.config;
import java.time.Duration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
@Configuration
publicclass RedisCacheSerializeConfiguration{
///**
// *二選一
// * 設定 redis資料預設過期時間設定@cacheable序列化方式
// *
// * @return
// */
//@Bean
//public RedisCacheConfiguration redisCacheConfiguration() {
// RedisCacheConfigurationconfiguration = RedisCacheConfiguration.defaultCacheConfig();
// configuration =configuration.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(valueSerializer()))
// .entryTtl(Duration.ofDays(30));
//configuration.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(keySerializer()));
// return configuration;
//}
/**
* 二選一
* 設定 redis資料預設過期時間設定@cacheable序列化方式
*
* @param connectionFactory
* @return
*/
@Bean
public RedisCacheManager cacheManager(RedisConnectionFactory connectionFactory) {
RedisCacheConfigurationconfig = RedisCacheConfiguration.defaultCacheConfig().entryTtl(Duration.ofDays(30))
.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(keySerializer()))
.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(valueSerializer()))
.disableCachingNullValues();
RedisCacheManager redisCacheManager = RedisCacheManager.builder(connectionFactory).cacheDefaults(config)
.transactionAware().build();
System.out.println("自定義RedisCacheManager加載完成");
returnredisCacheManager;
}
private RedisSerializer<String> keySerializer() {
returnnewStringRedisSerializer();
}
private RedisSerializer<Object> valueSerializer() {
returnnewGenericJackson2JsonRedisSerializer();
}
}
5、啟動相關類請參照源碼,目錄結構如下
6、編寫單元測試類
package sc.redis.cache;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import sc.redis.cache.model.User;
import sc.redis.cache.service.UserService;
@RunWith(SpringRunner.class)
@SpringBootTest
publicclass TestRedis {
privatestaticfinal Logger logger =LoggerFactory.getLogger(TestRedis.class);
@Autowired
privateUserService userService;
@Test
publicvoid add() {
User u = new User();
u.setId(4L);
u.setUserName("huangjinjin");
u.setPosition("cto");
u.setAge(24);
userService.addUser(u);
}
@Test
publicvoid get() {
User u =userService.getUser(4L);
logger.debug("userName = "+ u.getUserName());
}
}
7、進行單元測試
運作add方法添加一條資料到資料庫:
日志:
第一次運作get方法:
使用redis-cli檢視redis,資料已經插入緩存
第二次運作get方法:
發現沒有列印任何sql語句,說明資料是從redis擷取的,沒有去資料庫查詢資料。
源碼:
https://gitee.com/hjj520/spring-cloud-2.x/tree/master/sc-redis-cache
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