Spring Boot集成Druid数据库连接池 1. 前言 2. 配置pom.xml 3. 在application.yml中配置数据源 4. 打开Druid的监控统计功能

Druid数据库连接池由阿里巴巴开源,号称是java语言中最好的数据库连接池,是为监控而生的。Druid的官方地址是:https://github.com/alibaba/druid

通过本文,我们可以看到

  • Spring Boot 如何配置数据源
  • Spring Boot 如何集成Druid数据库连接池
  • 如何打开并访问Druid数据库连接池的监控功能
  • Spring Boot 使用JdbcTemplate操作数据库

2. 配置pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.3.5.RELEASE</version>
</parent>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.0.20</version>
    </dependency>
</dependencies>

 

3. 在application.yml中配置数据源

mybatis:
  type-aliases-package: com.haige.entity   # 起别名
  mapper-locations: /com/haige/repository/mapper/*.xml  # mapper映射文件的位置
server:
  port: 8080
spring:
  application:
    name: haige
  datasource:
    haige:
      # 数据库访问配置,mysql。
      # 主数据源,默认的
      type: com.alibaba.druid.pool.DruidDataSource
      driver-class-name: com.mysql.jdbc.Driver
      url: jdbc:mysql://localhost:3306/test
      username: root
      password: root
      # 下面为连接池的补充设置,应用到上面所有数据源中
      # 初始化大小,最小,最大
      initialSize: 5
      minIdle: 5
      maxActive: 20
      # 配置获取连接等待超时的时间
      maxWait: 60000
      # 配置间隔多久才进行一次检测,检测需要关闭的空闲连接,单位是毫秒
      timeBetweenEvictionRunsMillis: 60000
      # 配置一个连接在池中最小生存的时间,单位是毫秒
      minEvictableIdleTimeMillis: 300000
      validationQuery: SELECT 1 FROM DUAL
      testWhileIdle: true
      testOnBorrow: false
      #exceptionSorter: false
      testOnReturn: false
      poolPreparedStatements: true
      # 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
      maxPoolPreparedStatementPerConnectionSize: 20
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
      useGlobalDataSourceStat: true
      # 通过connectProperties属性来打开mergeSql功能;慢SQL记录
      #spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      # 合并多个DruidDataSource的监控数据
      #spring.datasource.useGlobalDataSourceStat=true
pagehelper:
  auto-dialect: "true"
  reasonable: "true"
  support-methods-arguments: "true"
  params: "count=countSql"
logging:
  config: classpath:log4j2.yml

4. 打开Druid的监控统计功能

Druid的监控统计功能是通过filter-chain扩展实现,如果你要打开监控统计功能,需要配置StatFilter,相关代码如下。

@Configuration
public class DruidConfiguration {

  private static final Logger log = LoggerFactory.getLogger(DruidConfiguration.class);

  @Bean
  public ServletRegistrationBean druidServlet() {
    log.info("init Druid Servlet Configuration ");
    ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean();
    servletRegistrationBean.setServlet(new StatViewServlet());
    servletRegistrationBean.addUrlMappings("/druid/*");
    Map<String, String> initParameters = new HashMap<String, String>();
    initParameters.put("loginUsername", "admin");// 用户名
    initParameters.put("loginPassword", "admin");// 密码
    initParameters.put("resetEnable", "false");// 禁用HTML页面上的“Reset All”功能
    initParameters.put("allow", ""); // IP白名单 (没有配置或者为空,则允许所有访问)
    //initParameters.put("deny", "192.168.20.38");// IP黑名单 (存在共同时,deny优先于allow)
    servletRegistrationBean.setInitParameters(initParameters);
    return servletRegistrationBean;
  }

  @Bean
  public FilterRegistrationBean filterRegistrationBean() {
    FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
    filterRegistrationBean.setFilter(new WebStatFilter());
    filterRegistrationBean.addUrlPatterns("/*");
    filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
    return filterRegistrationBean;
  }

}

注意:在spring-webflux项目中会出现

ServletRegistrationBean空指针,即servlet注册不进去,原因是webflux中没有引入servlet的包,解决方案如下,在启动类注册进去
@SpringBootApplication
public class HaigeApplication {
    public static void main(String[] args) {
        SpringApplication.run(HaigeApplication.class, args);
    }


    @Bean
    public RequestContextListener requestContextListener(){
        return new RequestContextListener();
    }
}

等应用启动后,可以访问地址:http://localhost:8080/druid/,用户名和密码见上述代码中的设置,即admin/admin。