安裝Redis請參考：《CentOS快速安裝Redis》
一、springboot集成redis並實現DB與緩存同步
1.添加redis及數據庫相關依賴（pom.xml）
<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-redis</artifactId> <version>1.4.7.RELEASE</version> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.1</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies>
2.添加數據庫、mybatis、redis相關配置（application.properties）
#數據庫相關配置 spring.datasource.driverClassName=com.mysql.jdbc.Driver spring.datasource.url=jdbc:mysql://192.168.15.129:3306/springboot?useUnicode=true&characterEncoding=utf-8&useSSL=false spring.datasource.username=root spring.datasource.password=123456 #Mybatis相關配置 mybatis.type-aliases-package=com.lianjinsoft.pojo mybatis.config-locations=classpath:mybatis/mybatis-config.xml mybatis.mapper-locations=classpath:mybatis/mapper/*.xml #Redis相關配置 #數據庫索引（默認為0） spring.redis.database=0 #服務器地址 spring.redis.host=192.168.15.129 #服務器連接端 spring.redis.port=6379 #服務器連接密碼（默認為空） spring.redis.password=123456 #連接池最大連接數（使用負值表示沒有限制） spring.redis.pool.max-active=100 #連接池最大阻塞等待時間（使用負值表示沒有限制） spring.redis.pool.max-wait=10000 #連接池中的最大空閑連接 spring.redis.pool.max-idle=8 #連接池中的最小空閑連接 spring.redis.pool.min-idle=2 #連接超時時間（毫秒） spring.redis.timeout=5000
3.springboot啟動類，增加Mybatis掃描注解
@MapperScan("com.lianjinsoft.mapper")
@SpringBootApplication
public class RedisApplication {
public static void main(String[] args) {
SpringApplication.run(RedisApplication.class, args);
}
}
4.增加pojo數據表映射類
public class Order {
private Integer id;
private String orderNo;
private String orderName;
private BigDecimal amount;
private Date addTime;
//省略get、set
}
5.增加Mapper數據持久層操作方法
public interface OrderMapper {
void addOrder(Order order);
void delOrder(String orderNo);
void updOrder(Order order);
Order queryOrderByNo(String orderNo);
}
6.增加Mybatis主配置文件
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <typeAliases> <typeAlias alias="Integer" type="java.lang.Integer" /> <typeAlias alias="Long" type="java.lang.Long" /> <typeAlias alias="HashMap" type="java.util.HashMap" /> <typeAlias alias="LinkedHashMap" type="java.util.LinkedHashMap" /> <typeAlias alias="ArrayList" type="java.util.ArrayList" /> <typeAlias alias="LinkedList" type="java.util.LinkedList" /> </typeAliases> </configuration>
7.增加Mapper對應的配置文件及sql
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.lianjinsoft.mapper.OrderMapper" > <resultMap id="BaseResultMap" type="com.lianjinsoft.pojo.Order" > <id column="id" property="id" jdbcType="INTEGER" /> <result column="order_no" property="orderNo" jdbcType="VARCHAR" /> <result column="order_name" property="orderName" jdbcType="VARCHAR" /> <result column="amount" property="amount" jdbcType="DECIMAL"/> <result column="add_time" property="addTime" jdbcType="TIMESTAMP" /> </resultMap> <sql id="Base_Column_List" > id, order_no, order_name, amount, add_time </sql> <select id="queryOrderByNo" parameterType="java.lang.String" resultMap="BaseResultMap" > SELECT <include refid="Base_Column_List" /> FROM orders WHERE order_no = #{orderNo} </select> <insert id="addOrder" parameterType="com.lianjinsoft.pojo.Order" > INSERT INTO orders (order_no,order_name,amount,add_time) VALUES (#{orderNo}, #{orderName}, #{amount}, #{addTime}) </insert> <delete id="delOrder" parameterType="java.lang.String" > DELETE FROM orders WHERE order_no =#{orderNo} </delete> <update id="updOrder" parameterType="com.lianjinsoft.pojo.Order" > UPDATE orders SET order_name=#{orderName} WHERE id=#{id} </update> </mapper>
8.添加緩存配置（啟用緩存）
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {
@Bean
public KeyGenerator keyGenerator() {
return new KeyGenerator() {
@Override
public Object generate(Object target, Method method, Object... params) {
StringBuilder sf = new StringBuilder();
sf.append(target.getClass().getName());
sf.append("_");
sf.append(method.getName());
for (Object obj : params) {
sf.append("_");
sf.append(obj.toString());
}
return sf.toString();
}
};
}
@Bean
public CacheManager cacheManager(RedisTemplate redisTemplate) {
return new RedisCacheManager(redisTemplate);
}
@Bean
public RedisTemplate<String, String> redisTemplate(RedisConnectionFactory factory) {
StringRedisTemplate template = new StringRedisTemplate(factory);
Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
ObjectMapper om = new ObjectMapper();
om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jackson2JsonRedisSerializer.setObjectMapper(om);
template.setValueSerializer(jackson2JsonRedisSerializer);
template.afterPropertiesSet();
return template;
}
}
9.增加OrderService接口及實現類
public interface OrderService {
void addOrder(Order order);
void delOrder(String orderNo);
void updOrder(Order order);
Order queryOrderByNo(String orderNo);
}
@Service
public class OrderServiceImpl implements OrderService{
private final String prefix = "order:";
@Autowired
private OrderMapper orderMapper;
@Autowired
private RedisTemplate redisTemplate;
@Override
public void addOrder(Order order) {
orderMapper.addOrder(order);
redisTemplate.opsForValue().set(prefix+order.getOrderNo(), order);
LogUtil.info("新增訂單，添加緩存："+order);
}
@Override
public void delOrder(String orderNo) {
if(redisTemplate.hasKey(prefix+orderNo)){
redisTemplate.delete(prefix+orderNo);
LogUtil.info("刪除緩存數據："+orderNo);
}
orderMapper.delOrder(orderNo);
}
@Override
public void updOrder(Order order) {
orderMapper.updOrder(order);
if(redisTemplate.hasKey(prefix+order.getOrderNo())){
redisTemplate.opsForValue().set(prefix+order.getOrderNo(), order);
LogUtil.info("更新緩存訂單信息："+order);
}
}
@Override
public Order queryOrderByNo(String orderNo) {
Order order = (Order)redisTemplate.opsForValue().get(prefix+orderNo);
if(order != null){
LogUtil.info("從緩存獲取到數據："+order);
return order;
}
order = orderMapper.queryOrderByNo(orderNo);
if(order != null){
redisTemplate.opsForValue().set(prefix+orderNo, order);
}
return order;
}
}
10.增加OrderServiceTests測試類（Junit）
@RunWith(SpringRunner.class)
@SpringBootTest
public class OrderServiceTests {
@Autowired
private OrderService orderService;
@Test
public void test1_add() {
//添加訂單
orderService.addOrder(new Order("100001", "XX手機", new BigDecimal("4999")));
}
@Test
public void test2_query() {
//查詢訂單
orderService.queryOrderByNo("100001");
}
@Test
public void test3_update() {
//先查詢訂單信息
Order order = orderService.queryOrderByNo("100001");
order.setOrderName("國民手機");
//更新DB及緩存
orderService.updOrder(order);
//再次查詢
orderService.queryOrderByNo("100001");
}
@Test
public void test4_del() {
//刪除DB及緩存
orderService.delOrder("100001");
//再次查詢
orderService.queryOrderByNo("100001");
}
}
10.1）執行test1_add()方法
10:57:45.873 [main] INFO c.l.service.OrderServiceTests - Starting OrderServiceTests on LAPTOP-1DF7S904 with PID 8316 (started by lianjinsoft in E:\workspace\springboot\spring-boot-redis) 10:57:45.875 [main] INFO c.l.service.OrderServiceTests - No active profile set, falling back to default profiles: default 10:57:45.908 [main] INFO o.s.c.a.AnnotationConfigApplicationContext - Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:57:45 CST 2018]; root of context hierarchy 10:57:46.233 [main] INFO o.s.d.r.c.RepositoryConfigurationDelegate - Multiple Spring Data modules found, entering strict repository configuration mode! 10:57:47.370 [main] WARN o.s.b.s.r.RedisStarterDeprecationWarningAutoConfiguration - spring-boot-starter-redis is deprecated as of Spring Boot 1.4, please migrate to spring-boot-starter-data-redis 10:57:47.399 [main] INFO c.l.service.OrderServiceTests - Started OrderServiceTests in 1.752 seconds (JVM running for 2.512) 10:57:47.931 [main] INFO com.lianjinsoft.util.LogUtil - 新增訂單，添加緩存：Order [id=null, orderNo=100001, orderName=XX手機, amount=4999, addTime=Mon Apr 23 10:57:47 CST 2018] 10:57:47.939 [Thread-2] INFO o.s.c.a.AnnotationConfigApplicationContext - Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:57:45 CST 2018]; root of context hierarchy
從日志的第7行可以看出，訂單信息已經添加成功。並添加到緩存中。
10.2）執行test2_query()方法
10:58:04.273 [main] INFO c.l.service.OrderServiceTests - Starting OrderServiceTests on LAPTOP-1DF7S904 with PID 20492 (started by lianjinsoft in E:\workspace\springboot\spring-boot-redis) 10:58:04.277 [main] INFO c.l.service.OrderServiceTests - No active profile set, falling back to default profiles: default 10:58:04.301 [main] INFO o.s.c.a.AnnotationConfigApplicationContext - Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:58:04 CST 2018]; root of context hierarchy 10:58:04.618 [main] INFO o.s.d.r.c.RepositoryConfigurationDelegate - Multiple Spring Data modules found, entering strict repository configuration mode! 10:58:05.920 [main] WARN o.s.b.s.r.RedisStarterDeprecationWarningAutoConfiguration - spring-boot-starter-redis is deprecated as of Spring Boot 1.4, please migrate to spring-boot-starter-data-redis 10:58:05.953 [main] INFO c.l.service.OrderServiceTests - Started OrderServiceTests in 1.903 seconds (JVM running for 2.659) 10:58:06.101 [main] INFO com.lianjinsoft.util.LogUtil - 從緩存獲取數據：Order [id=null, orderNo=100001, orderName=XX手機, amount=4999, addTime=Mon Apr 23 10:57:47 CST 2018] 10:58:06.109 [Thread-2] INFO o.s.c.a.AnnotationConfigApplicationContext - Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:58:04 CST 2018]; root of context hierarchy
從日志的第7行可以看出，查詢信息從緩存中獲取（沒有查詢數據庫）。
10.3）執行test3_update()方法
10:58:17.172 [main] INFO c.l.service.OrderServiceTests - Starting OrderServiceTests on LAPTOP-1DF7S904 with PID 12316 (started by lianjinsoft in E:\workspace\springboot\spring-boot-redis) 10:58:17.172 [main] INFO c.l.service.OrderServiceTests - No active profile set, falling back to default profiles: default 10:58:17.207 [main] INFO o.s.c.a.AnnotationConfigApplicationContext - Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:58:17 CST 2018]; root of context hierarchy 10:58:17.530 [main] INFO o.s.d.r.c.RepositoryConfigurationDelegate - Multiple Spring Data modules found, entering strict repository configuration mode! 10:58:18.679 [main] WARN o.s.b.s.r.RedisStarterDeprecationWarningAutoConfiguration - spring-boot-starter-redis is deprecated as of Spring Boot 1.4, please migrate to spring-boot-starter-data-redis 10:58:18.750 [main] INFO c.l.service.OrderServiceTests - Started OrderServiceTests in 1.809 seconds (JVM running for 2.553) 10:58:19.032 [main] INFO com.lianjinsoft.util.LogUtil - 從緩存獲取數據：Order [id=null, orderNo=100001, orderName=XX手機, amount=4999, addTime=Mon Apr 23 10:57:47 CST 2018] 10:58:19.450 [main] INFO com.lianjinsoft.util.LogUtil - 更新緩存訂單信息：Order [id=null, orderNo=100001, orderName=國民手機, amount=4999, addTime=Mon Apr 23 10:57:47 CST 2018] 10:58:19.454 [main] INFO com.lianjinsoft.util.LogUtil - 從緩存獲取數據：Order [id=null, orderNo=100001, orderName=國民手機, amount=4999, addTime=Mon Apr 23 10:57:47 CST 2018] 10:58:19.458 [Thread-2] INFO o.s.c.a.AnnotationConfigApplicationContext - Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:58:17 CST 2018]; root of context hierarchy
從日志的第7~9行可以看出，訂單先從緩存中獲取，然后執行了更新DB、更新緩存，最后再從緩存中獲取到了訂單信息。
10.4）執行test4_del()方法
10:58:34.652 [main] INFO c.l.service.OrderServiceTests - Starting OrderServiceTests on LAPTOP-1DF7S904 with PID 7428 (started by lianjinsoft in E:\workspace\springboot\spring-boot-redis) 10:58:34.652 [main] INFO c.l.service.OrderServiceTests - No active profile set, falling back to default profiles: default 10:58:34.676 [main] INFO o.s.c.a.AnnotationConfigApplicationContext - Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:58:34 CST 2018]; root of context hierarchy 10:58:34.997 [main] INFO o.s.d.r.c.RepositoryConfigurationDelegate - Multiple Spring Data modules found, entering strict repository configuration mode! 10:58:36.107 [main] WARN o.s.b.s.r.RedisStarterDeprecationWarningAutoConfiguration - spring-boot-starter-redis is deprecated as of Spring Boot 1.4, please migrate to spring-boot-starter-data-redis 10:58:36.140 [main] INFO c.l.service.OrderServiceTests - Started OrderServiceTests in 1.856 seconds (JVM running for 2.61) 10:58:36.281 [main] INFO com.lianjinsoft.util.LogUtil - 刪除緩存數據：100001 10:58:36.689 [main] INFO com.lianjinsoft.util.LogUtil - 從數據庫獲取數據：null 10:58:36.693 [Thread-2] INFO o.s.c.a.AnnotationConfigApplicationContext - Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@306cf3ea: startup date [Mon Apr 23 10:58:34 CST 2018]; root of context hierarchy
從日志的第7、8行可以看出，訂單信息已經從DB、緩存中刪除了。
注意：
本案例只是簡單的介紹如何將DB與緩存數據同步操作，並不一定適合您當前的業務需求。並且以上操作不能保證緩存與DB數據完全一致。
二、springboot集成redis並實現分布式session緩存
分布式session共享有很多方案，其中緩存托管就是主流一種實現。
1.添加session緩存相關依賴（pom.xml）
<dependency> <groupId>org.springframework.session</groupId> <artifactId>spring-session-data-redis</artifactId> </dependency>
2.添加session配置（啟用session緩存）
maxInactiveIntervalInSeconds: 設置session失效時間。
@Configuration
@EnableRedisHttpSession(maxInactiveIntervalInSeconds = 60*30)
public class SessionConfig {
}
3.測試
3.1）修改本地服務端口並啟動，模擬分布式應用部署（application.properties）
#服務端口（8001、8002、8003）
server.port=8001
3.2）分別調用各應用接口，查看sessionId
3.3）查看redis緩存信息
如圖：緩存中的sessionId與接口返回信息一致。
源代碼：https://gitee.com/skychenjiajun/spring-boot