21.使用druid作为springboot项目数据源（添加监控）

1，添加 druid 的jar

com.alibaba
druid
1.0.29

2，配置 DruidConfiguration 类

package com.yuqiyu.character3;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class DruidConfiguration {
    @Bean
    public ServletRegistrationBean statViewServlet(){
        //创建servlet注册实体
  ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
        //设置ip白名单
        servletRegistrationBean.addInitParameter("allow","127.0.0.1");
        //设置ip黑名单，如果allow与deny共同存在时,deny优先于allow
  servletRegistrationBean.addInitParameter("deny","192.168.0.19");
        //设置控制台管理用户
        servletRegistrationBean.addInitParameter("loginUsername","druid");
        servletRegistrationBean.addInitParameter("loginPassword","123456");
  //是否可以重置数据
        servletRegistrationBean.addInitParameter("resetEnable","false");
        return servletRegistrationBean;
    }
 @Bean
    public FilterRegistrationBean statFilter(){
        //创建过滤器
   FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
        //设置过滤器过滤路径
        filterRegistrationBean.addUrlPatterns("/*");
   //忽略过滤的形式
        filterRegistrationBean.addInitParameter("exclusions","*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
        return filterRegistrationBean;
    }
}

3，yml配置

spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/test?characterEncoding=utf8
    username: root
    password: root
    #最大活跃数
    maxActive: 20
    #初始化数量
    initialSize: 1
    #最大连接等待超时时间
    maxWait: 60000
    #打开PSCache，并且指定每个连接PSCache的大小
    poolPreparedStatements: true
    maxPoolPreparedStatementPerConnectionSize: 20
    #通过connectionProperties属性来打开mergeSql功能；慢SQL记录
    #connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
    minIdle: 1
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: select 1 from dual
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    #配置监控统计拦截的filters，去掉后监控界面sql将无法统计,'wall'用于防火墙
    filters: stat, wall, log4j
  jpa:
    properties:
      hibernate:
        show_sql: true
        format_sql: true

4，项目运行成功后，我们要访问Druid的监控界面，访问地址：127.0.0.1:8080/druid/login.html， 输入配置的用户名和密码