引入Druid依赖

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.1.1</version>
</dependency>
切记，需引入当前依赖，引入
 
<dependency>  
    <groupId>com.alibaba</groupId>  
    <artifactId>druid</artifactId>  
    <version>1.1.5</version>  
</dependency>
依赖，会出现 
java.sql.SQLException: validateConnection false 
报错。

application.yml中配置Druid连接信息，如下： 

###################以下为druid增加的配置###########################
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
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
testWhileIdle: true
testOnBorrow: false
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，此处是filter修改的地方
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
useGlobalDataSourceStat: true

新建Druid缓存配置类DruidConfiguration

package com.example.demo.config;

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 statViesServle(){
        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
        //IP白名单
        servletRegistrationBean.addInitParameter("allow","192.168.1.100,127.0.0.1");
        //IP黑名单(共同存在时，deny优先于allow)
        servletRegistrationBean.addInitParameter("deny","192.168.1.101");
        servletRegistrationBean.addInitParameter("loginUsername","druid");
        servletRegistrationBean.addInitParameter("loginPassword","123456");
        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;
    }
}

配置完成后，通过http://127.0.0.1/druid/index.html 访问druid后台。