阿里巴巴Druid数据库连接池的使用

准备：

　　创建一个基于SpringBoot的web项目

1 引入相关依赖

　　jpa、mysql、druid

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>cn.xiangxu</groupId>
    <artifactId>qcbx</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>qcbx</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </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>

        <!--数据库相关-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.18</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

2 配置数据库连接信息

server: # 服务配置
  port: 80
#  context-path: /dev
spring:
  datasource: # 数据库连接池配置
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/springdemo?useUnicode=true&characterEncoding=UTF-8
    username: root
    password: asdf

    type: com.alibaba.druid.pool.DruidDataSource
    #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
    #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
#    filters: stat

  jpa: # jpa配置
    hibernate:
#      ddl-auto: create # 会在首次启动的时候根据相应的实体类在数据库中创建相应的表，如果之前有表了，就会删掉在重建
#      ddl-auto: update # 如果没有表会创建，有表会对表结构进行修改
#     ddl-auto:create-drop # 应用停下来时会将表删掉
      ddl-auto: none  # 什么都不做（默认值）
#      ddl-auto: validate # 检查实体类字段和表字段是否一致，如果不一致就会报错
    show-sql: true # 执行数据库操作时会打印出相应的SQL语句

#  mvc:
#    view: # jsp文件路径设置
#      prefix: /WEB-INF/jsp/ # jsp视图前缀
#      suffix: .jsp # jsp视图后缀

  http:
    multipart: # 上传文件大小设置
      max-file-size: 1024Mb # 设置最大上传大小
      max-request-size: 2048Mb # 设置最大请求大小

#  redis: # rediss缓存设置
#    host: 127.0.0.1 # 监听IP地址
#    port: 6379 # 端口号
#    pool:
#      max-idle: 20
#      min-idle: 1
#      max-active: 20
#      max-wait: 60000
#    database: 0

logging: # 日志配置
  level:
#    cn.xiangxu.spring.controller.logger: ‘off‘ # 屏蔽掉相应包的日志控制台输出和日记文件保存

3 配置druid

package cn.xiangxu.qcbx.configuration;

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;

/**
 * Druid配置
 */
@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","wys");
        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;
    }
}

4 启动成功效果