Java程序很大一部分要操作数据库,为了提高性能操作数据库的时候,又不得不使用数据库连接池。
Druid 是阿里巴巴开源平台上一个数据库连接池实现,结合了 C3P0、DBCP 等 DB 池的优点,同时加入了日志监控。
Druid 可以很好的监控 DB 池连接和 SQL 的执行情况,天生就是针对监控而生的 DB 连接池。
<dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.2.8</version> </dependency>
server: port: 8080 spring: datasource: druid: url: jdbc:mysql://localhost:3306/eshop?useSSL=false&serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8&allowPublicKeyRetrieval=true username: xxx password: xxx driver-class-name: com.mysql.cj.jdbc.Driver initial-size: 10 max-active: 20 min-idle: 10 max-wait: 60000 time-between-eviction-runs-millis: 60000 min-evictable-idle-time-millis: 300000 stat-view-servlet: enabled: true login-username: admin login-password: 1234 logging: level: com.wyy.spring.Dao: debug
测试一下看是否成功!
package com.wyy.spring; import com.wyy.spring.Dao.StudentMapper; import com.wyy.spring.service.StudentService; import org.junit.jupiter.api.Test; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import javax.sql.DataSource; @SpringBootTest class SpringBoot04ApplicationTests { @Autowired DataSource dataSource; @Test void contextLoads() { System.out.println(dataSource.getClass()); } }
打印结果
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency>
redis: database: 0 host: 120.0.0.0 port: 6379 password: xxxx jedis: pool: max-active: 8 max-wait: -1 max-idle: 8 min-idle: 0 timeout: 10000
package com.wyy.spring.conf; import org.springframework.cache.CacheManager; import org.springframework.cache.annotation.CachingConfigurerSupport; import org.springframework.cache.annotation.EnableCaching; import org.springframework.cache.interceptor.KeyGenerator; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.Primary; 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.core.RedisTemplate; 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; import org.springframework.util.ClassUtils; import java.lang.reflect.Array; import java.lang.reflect.Method; import java.time.Duration; @Configuration @EnableCaching public class RedisConfiguration extends CachingConfigurerSupport { @Bean @Primary /** * 缓存管理器 */ CacheManager cacheManager(RedisConnectionFactory factory) { RedisCacheConfiguration cacheConfiguration = RedisCacheConfiguration.defaultCacheConfig() .computePrefixWith(cacheName -> cacheName + ":-cache-:") /*设置缓存过期时间*/ .entryTtl(Duration.ofHours(1)) /*禁用缓存空值,不缓存null校验*/ .disableCachingNullValues() /*设置CacheManager的值序列化方式为json序列化,可使用加入@Class属性*/ .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer( new GenericJackson2JsonRedisSerializer() )); /*使用RedisCacheConfiguration创建RedisCacheManager*/ RedisCacheManager manager = RedisCacheManager.builder(factory) .cacheDefaults(cacheConfiguration) .build(); return manager; } public RedisTemplate redisTemplate(RedisConnectionFactory factory) { RedisTemplate<String, Object> redisTemplate = new RedisTemplate<String, Object>(); redisTemplate.setConnectionFactory(factory); RedisSerializer stringSerializer = new StringRedisSerializer(); /* key序列化 */ redisTemplate.setKeySerializer(stringSerializer); /* value序列化 */ redisTemplate.setValueSerializer(new GenericJackson2JsonRedisSerializer()); /* Hash key序列化 */ redisTemplate.setHashKeySerializer(stringSerializer); /* Hash value序列化 */ redisTemplate.setHashValueSerializer(new GenericJackson2JsonRedisSerializer()); redisTemplate.afterPropertiesSet(); return redisTemplate; @Override public KeyGenerator keyGenerator() { return (Object target, Method method, Object... params) -> { final int NO_PARAM_KEY = 0; final int NULL_PARAM_KEY = 53; StringBuilder key = new StringBuilder(); /* Class.Method: */ key.append(target.getClass().getSimpleName()) .append(".") .append(method.getName()) .append(":"); if (params.length == 0) { return key.append(NO_PARAM_KEY).toString(); } int count = 0; for (Object param : params) { /* 参数之间用,进行分隔 */ if (0 != count) { key.append(','); } if (param == null) { key.append(NULL_PARAM_KEY); } else if (ClassUtils.isPrimitiveArray(param.getClass())) { int length = Array.getLength(param); for (int i = 0; i < length; i++) { key.append(Array.get(param, i)); key.append(','); } } else if (ClassUtils.isPrimitiveOrWrapper(param.getClass()) || param instanceof String) { key.append(param); } else { /*JavaBean一定要重写hashCode和equals*/ key.append(param.hashCode()); count++; return key.toString(); }; }
@CacheConfig 一个类级别的注解,允许共享缓存的cacheNames、KeyGenerator、CacheManager 和 CacheResolver
@Cacheable 用来声明方法是可缓存的。将结果存储到缓存中以便后续使用相同参数调用时不需执行实际的方 法。直接从缓存中取值
@CachePut 标注的方法在执行前不会去检查缓存中是否存在之前执行过的结果,而是每次都会执行该方法, 并将执行结果以键值对的形式存入指定的缓存中。
@CacheEvict 的作用 主要针对方法配置,能够根据一定的条件对缓存进行清空