spring boot集成druid数据库连接池，实现对数据库的监控

一、加入druid依赖

		
			com.alibaba
			druid
			1.0.27
		

二、在application.properties配置文件中加入druid配置

# 初始化大小，最小，最大
spring.datasource.initialSize=5
spring.datasource.minIdle=5
spring.datasource.maxActive=20
# 配置获取连接等待超时的时间
spring.datasource.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
spring.datasource.timeBetweenEvictionRunsMillis=60000
# 配置一个连接在池中最小生存的时间，单位是毫秒
spring.datasource.minEvictableIdleTimeMillis=300000
# 校验SQL，Oracle配置 spring.datasource.validationQuery=SELECT 1 FROM DUAL，如果不配validationQuery项，则下面三项配置无用
spring.datasource.validationQuery=SELECT 'x'
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
# 打开PSCache，并且指定每个连接上PSCache的大小
spring.datasource.poolPreparedStatements=true
spring.datasource.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
spring.datasource.filters=stat,wall,log4j
# 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

三、配置WebFilter

package com.chhliu.springboot.jpa;

import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;

import com.alibaba.druid.support.http.WebStatFilter;

@WebFilter(filterName="druidStatFilter",urlPatterns="/*",
initParams={
        @WebInitParam(name="exclusions",value="*.js,*.gif,*.jpg,*.bmp,*.png,*.css,*.ico,/druid/*")// 忽略资源
})
public class DruidStatFilter extends WebStatFilter {

}

四、配置WebServlet

package com.chhliu.springboot.jpa;

import javax.servlet.annotation.WebInitParam;
import javax.servlet.annotation.WebServlet;

import com.alibaba.druid.support.http.StatViewServlet;

@WebServlet(urlPatterns = "/druid/*",
initParams={
        @WebInitParam(name="allow",value="127.0.0.1"),// IP白名单 (没有配置或者为空，则允许所有访问)
        @WebInitParam(name="deny",value="192.168.0.0"),// IP黑名单 (存在共同时，deny优先于allow)
        @WebInitParam(name="loginUsername",value="admin"),// druid监控页面登陆用户名
        @WebInitParam(name="loginPassword",value="admin"),// druid监控页面登陆密码
        @WebInitParam(name="resetEnable",value="false")// 禁用HTML页面上的“Reset All”功能
})
public class DruidStatViewServlet extends StatViewServlet {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

}

五、扫描Servlet

package com.chhliu.springboot.jpa;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

@SpringBootApplication
@EnableEurekaClient
@ServletComponentScan // 注意要加上@ServletComponentScan注解，否则Servlet无法生效
public class SpringbootJpaDruidApplication {

	public static void main(String[] args) {
		SpringApplication.run(SpringbootJpaDruidApplication.class, args);
	}
}

六、启动应用程序

1、在浏览器中输入http://localhost:7602/druid/login.html登陆

2、登陆进去后，监控页面如下：

经过测试发现，无论我们怎么操作，SQL监控一直都显示不出任何的内容，当前使用的spring boot版本为1.4.x版本

七、不使用spring boot自动配置功能，手动初始化DataSource

package com.chhliu.springboot.jpa;

import java.sql.SQLException;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import com.alibaba.druid.pool.DruidDataSource;

/**
 * 
 * 描述：如果不使用代码手动初始化DataSource的话，监控界面的SQL监控会没有数据("是spring boot的bug???")
 * @author chhliu
 * 创建时间：2017年2月9日 下午10:33:08
 * @version 1.2.0
 */
@Configuration
public class DruidConfiguration {
    @Value("${spring.datasource.url}")
    private String dbUrl;
    @Value("${spring.datasource.username}")
    private String username;
    @Value("${spring.datasource.password}")
    private String password;
    @Value("${spring.datasource.driverClassName}")
    private String driverClassName;
    @Value("${spring.datasource.initialSize}")
    private int initialSize;
    @Value("${spring.datasource.minIdle}")
    private int minIdle;
    @Value("${spring.datasource.maxActive}")
    private int maxActive;
    @Value("${spring.datasource.maxWait}")
    private int maxWait;
    @Value("${spring.datasource.timeBetweenEvictionRunsMillis}")
    private int timeBetweenEvictionRunsMillis;
    @Value("${spring.datasource.minEvictableIdleTimeMillis}")
    private int minEvictableIdleTimeMillis;
    @Value("${spring.datasource.validationQuery}")
    private String validationQuery;
    @Value("${spring.datasource.testWhileIdle}")
    private boolean testWhileIdle;
    @Value("${spring.datasource.testOnBorrow}")
    private boolean testOnBorrow;
    @Value("${spring.datasource.testOnReturn}")
    private boolean testOnReturn;
    @Value("${spring.datasource.poolPreparedStatements}")
    private boolean poolPreparedStatements;
    @Value("${spring.datasource.maxPoolPreparedStatementPerConnectionSize}")
    private int maxPoolPreparedStatementPerConnectionSize;
    @Value("${spring.datasource.filters}")
    private String filters;
    @Value("${spring.datasource.connectionProperties}")
    private String connectionProperties;
    @Value("${spring.datasource.useGlobalDataSourceStat}")
    private boolean useGlobalDataSourceStat;

    @Bean     //声明其为Bean实例
    @Primary  //在同样的DataSource中，首先使用被标注的DataSource
    public DataSource dataSource(){
        DruidDataSource datasource = new DruidDataSource();
        datasource.setUrl(this.dbUrl);
        datasource.setUsername(username);
        datasource.setPassword(password);
        datasource.setDriverClassName(driverClassName);

        //configuration
        datasource.setInitialSize(initialSize);
        datasource.setMinIdle(minIdle);
        datasource.setMaxActive(maxActive);
        datasource.setMaxWait(maxWait);
        datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
        datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setValidationQuery(validationQuery);
        datasource.setTestWhileIdle(testWhileIdle);
        datasource.setTestOnBorrow(testOnBorrow);
        datasource.setTestOnReturn(testOnReturn);
        datasource.setPoolPreparedStatements(poolPreparedStatements);
        datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
        datasource.setUseGlobalDataSourceStat(useGlobalDataSourceStat);
        try {
            datasource.setFilters(filters);
        } catch (SQLException e) {
            System.err.println("druid configuration initialization filter: "+ e);
        }
        datasource.setConnectionProperties(connectionProperties);
        return datasource;
    }
}

注意：上面的这个类需要放到和application同级的目录下，这样才能在程序启动的时候初始化DataSource

修改过后结果如下：

发现，SQL监控页面有内容了。估计这个问题是spring boot在升级过程中产生的一个bug。