Druid简介
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。
Druid已经在阿里巴巴部署了超过600个应用，经过一年多生产环境大规模部署的严苛考验。
Spring Boot 2.0 以上默认使用 Hikari 数据源，可以说 Hikari 与 Driud 都是当前 Java Web 上最优秀的数据源，我们来重点介绍 Spring Boot 如何集成 Druid 数据源，如何实现数据库监控。
pom.xml
<!--数据库驱动--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <!--lombok--> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <!--mybatis-plus--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.0.5</version> </dependency> <!-- druid --> <!--引入druid数据源--> <!-- https://mvnrepository.com/artifact/com.alibaba/druid --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.21</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency>application.yml
#服务的名称 spring: application: name: product-service ########-spring datasource-######## datasource: #账号配置 url: jdbc:mysql://bt.jfgapp.com:3306/springcould?useSSL=true&useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC username: springcould password: springcould@ driver-class-name: com.mysql.cj.jdbc.Driver #druid连接池配置 type: com.alibaba.druid.pool.DruidDataSource initialSize: 5 minIdle: 5 maxActive: 20 maxWait: 60000 timeBetweenEvictionRunsMillis: 60000 minEvictableIdleTimeMillis: 300000 validationQuery: SELECT 1 FROM DUAL testWhileIdle: true testOnBorrow: false testOnReturn: false poolPreparedStatements: true maxPoolPreparedStatementPerConnectionSize: 20 #配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙 filters: stat,wall,log4j connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000 # mybatis-plus相关配置 mybatis-plus: # xml扫描，多个目录用逗号或者分号分隔（告诉 Mapper 所对应的 XML 文件位置） mapper-locations: classpath:mapper/*.xml # 以下配置均有默认值,可以不设置 global-config: db-config: #主键类型 auto:"数据库ID自增" 1:"用户输入ID",2:"全局唯一ID (数字类型唯一ID)", 3:"全局唯一ID UUID"; id-type: auto #字段策略 IGNORED:"忽略判断" NOT_NULL:"非 NULL 判断") NOT_EMPTY:"非空判断" field-strategy: NOT_EMPTY #数据库类型 db-type: MYSQL #驼峰下划线转换 db-column-underline: true #mp2.3+ 全局表前缀 p_ #table-prefix: mp_ #刷新mapper 调试神器 refresh-mapper: true #数据库大写下划线转换 #capital-mode: true #逻辑删除配置（下面3个配置） logic-delete-value: 4 logic-not-delete-value: 0 configuration: #配置返回数据库(column下划线命名&&返回java实体是驼峰命名)，自动匹配无需as（没开启这个，SQL需要写as： select user_id as userId） map-underscore-to-camel-case: true # 如果查询结果中包含空值的列，则 MyBatis 在映射的时候，不会映射这个字段 call-setters-on-nulls: true cache-enabled: false #配置JdbcTypeForNull, oracle数据库必须配置 jdbc-type-for-null: 'null' # 这个配置会将执行的sql打印出来，在开发或测试的时候可以用 log-impl: org.apache.ibatis.logging.stdout.StdOutImplpackage com.sxpcwlkj.product_server.config; import com.alibaba.druid.support.http.StatViewServlet; import com.alibaba.druid.support.http.WebStatFilter; import org.springframework.context.annotation.Configuration; import org.springframework.boot.web.servlet.FilterRegistrationBean; import org.springframework.boot.web.servlet.ServletRegistrationBean; import org.springframework.context.annotation.Bean; /** * @author Alan Chen * @description Druid连接池监控平台 http://localhost:8080/druid/index.html * @date 2019/6/4 */ @Configuration public class DruidConfiguration { @Bean public ServletRegistrationBean startViewServlet(){ ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*"); // IP白名单 servletRegistrationBean.addInitParameter("allow","127.0.0.1"); // IP黑名单(共同存在时，deny优先于allow) servletRegistrationBean.addInitParameter("deny","127.0.0.2"); //控制台管理用户 servletRegistrationBean.addInitParameter("loginUsername","admin"); servletRegistrationBean.addInitParameter("loginPassword","123456"); //是否能够重置数据 servletRegistrationBean.addInitParameter("resetEnable","false"); return servletRegistrationBean; } @Bean public FilterRegistrationBean statFilter(){ FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter()); //添加过滤规则 filterRegistrationBean.addUrlPatterns("/*"); //忽略过滤的格式 filterRegistrationBean.addInitParameter("exclusions","*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*"); return filterRegistrationBean; } }package com.sxpcwlkj.product_server.config; import com.alibaba.druid.pool.DruidDataSource; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import javax.sql.DataSource; @Configuration public class DruidConfig { @ConfigurationProperties(prefix = "spring.datasource") @Bean public DataSource druid() { return new DruidDataSource(); } } package com.sxpcwlkj.product_server.config; import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor; import org.springframework.boot.autoconfigure.condition.ConditionalOnClass; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; /** * MybatisPlus 配置 */ @Configuration @ConditionalOnClass(value = {PaginationInterceptor.class}) public class MybatisPlusConfig { @Bean public PaginationInterceptor paginationInterceptor() { PaginationInterceptor paginationInterceptor = new PaginationInterceptor(); return paginationInterceptor; } }