SpringBoot使用druid最为数据连接池以及监控

1、在项目的pom.xml文件中添加druid的依赖：

<!-- druid数据连接池 -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.1.0</version>
</dependency>

2、向SpringBoot容器配置druid，编写配置类 DruidConfig.class：

@Configuration
@ConditionalOnClass(com.alibaba.druid.pool.DruidDataSource.class)
@ConditionalOnProperty(name = "spring.datasource.type", havingValue = "com.alibaba.druid.pool.DruidDataSource", matchIfMissing = true)
public class DruidConfig {

    @SuppressWarnings("unchecked")
    protected <T> T createDataSource(DataSourceProperties properties,
                                     Class<? extends DataSource> type) {
        return (T) properties.initializeDataSourceBuilder().type(type).build();
    }

    /**
     * @see org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration.Tomcat
     * @param properties 读入的配置
     * @return DruidDataSource
     */
    @Bean
    @ConfigurationProperties("spring.datasource.druid")
    public com.alibaba.druid.pool.DruidDataSource dataSource(DataSourceProperties properties) {

        com.alibaba.druid.pool.DruidDataSource dataSource = createDataSource(
                properties, com.alibaba.druid.pool.DruidDataSource.class);

        DatabaseDriver databaseDriver = DatabaseDriver.fromJdbcUrl(properties.determineUrl());

        String validationQuery = databaseDriver.getValidationQuery();
        if (validationQuery != null) {
            dataSource.setTestOnBorrow(true);
            dataSource.setValidationQuery(validationQuery);
        }

        return dataSource;
    }

    /**
     * 注册一个StatViewServlet
     */
    @Bean
    public ServletRegistrationBean druidStatViewServlet(){
        //org.springframework.boot.context.embedded.ServletRegistrationBean提供类的进行注册.
        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");

        //添加初始化参数：initParams
        //白名单：
        servletRegistrationBean.addInitParameter("allow","127.0.0.1");
        //IP黑名单 (存在共同时，deny优先于allow) : 如果满足deny的话提示:Sorry, you are not permitted to view this page.
        servletRegistrationBean.addInitParameter("deny","192.168.1.73");
        //登录查看信息的账号密码.
        servletRegistrationBean.addInitParameter("loginUsername","root");
        servletRegistrationBean.addInitParameter("loginPassword","123456");
        //是否能够重置数据.
        servletRegistrationBean.addInitParameter("resetEnable","false");
        // 禁用HTML页面上的“Reset All”功能
        return servletRegistrationBean;
    }

    /**
     * 注册一个：filterRegistrationBean
     * 过滤拦截
     */
    @Bean
    public FilterRegistrationBean druidStatFilter(){

        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
        filterRegistrationBean.setName("druidWebStatFilter");
        //添加过滤规则.
        filterRegistrationBean.addUrlPatterns("/*");
        //添加忽略的格式信息.
        filterRegistrationBean.addInitParameter("exclusions","*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
        return filterRegistrationBean;
    }

}

3、在配置文件application.yml中配置参数：

datasource:
  driver-class-name: com.mysql.jdbc.Driver
  url: jdbc:mysql://127.0.0.1/demo?charactEncoding=utf-8&useSSL=false
  username: root
  password: 123456
  database: MYSQL
  show-sql: true
  hibernate: org.hibernate.cfg.ImprovedNamingStrategy
  name: druid
  type: com.alibaba.druid.pool.DruidDataSource
  # 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
  druid:
    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 t_user
    testWhileIdle: true
    testOnBorrow: true
    testOnReturn: false
    # 打开PSCache，并且指定每个连接上PSCache的大小
    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
    # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
    # 合并多个DruidDataSource的监控数据
    # spring.datasource.druid.useGlobalDataSourceStat=true

4、启动项目后，访问http://localhost:8080/druid/login.html，输入配置类DruidConfig.class中设置的用户名和密码：

登录进去就可以看见控制台页面，查看监控的详细信息。