spring boot配置druid连接池连接mysql
概述
spring boot现在的默认连接池是Hikari,号称是性能最好的连接池,不过国内使用较多的是阿里开源的druid连接池,在阿里的诸多项目中经过实践验证,本文介绍怎样在spring boot中集成druid。
准备数据
我们会使用与教程spring boot 连接 mysql同样的数据,如无数据请参照该教程准备数据,该教程详细介绍了通过mysql图形客户端workbench生成数据的过程。如果倾向使用mysql命令行客户端,下面是创建数据库和插入数据的sql语句。
sql语句
mysql命令行客户端连接数据库:
mysql -h localhost -u root -p
创建数据库
CREATE DATABASE qikegu_demo CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
创建表的sql语句:
CREATE TABLE `qikegu_demo`.`user` (
`id` BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT 'id',
`nickname` VARCHAR(50) NULL COMMENT '昵称',
`mobile` VARCHAR(20) NULL COMMENT '手机号',
`password` CHAR(60) NULL COMMENT '密码hash值',
`role` VARCHAR(100) NULL DEFAULT 'user' COMMENT '角色,角色名以逗号分隔',
PRIMARY KEY (`id`),
UNIQUE INDEX `mobile_UNIQUE` (`mobile` ASC))
COMMENT = '用户表';
插入数据的sql语句:
INSERT INTO `qikegu_demo`.`user` (`nickname`, `mobile`, `password`) VALUES ('abc1', '13512345678', '123');
INSERT INTO `qikegu_demo`.`user` (`nickname`, `mobile`, `password`) VALUES ('abc2', '13512345677', '123');
创建项目
创建 spring boot项目
打开Eclipse,创建spring boot的spring starter project项目,在配置依赖时,勾选web, jdbc, mysql,如不清楚怎样创建spring boot项目,参照教程: spring boot hello world (restful接口)例子
添加druid依赖
在pom.xml文件中,添加druid依赖
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
完整的pom.xml文件内容如下:
<?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>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.qikegu</groupId>
<artifactId>druid-demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>druid-demo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
配置数据库
application.properties配置
打开文件:application.properties,该文件在 src -> main -> resources
目录,配置数据库连接:
# 服务器端口
server.port=8096
# 数据库设置
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/qikegu_demo?serverTimezone=UTC&useUnicode=true&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=你的数据库密码
# druid配置
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
# druid参数调优(可选)
# 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
# 测试连接
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
spring.datasource.filters=stat
# asyncInit是1.1.4中新增加的配置,如果有initialSize数量较多时,打开会加快应用启动时间
spring.datasource.asyncInit=true
解释请看代码注释。druid必须的配置其实很少,只需配置一行,表明不使用默认的Hikari,而使用druid。
# druid配置
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
参数调优部分是可选的,这里列出的参数都是druid官网推荐的典型配置。另外还有监控配置,一般使用不用去管它。
DruidConfig.java配置
由于现在Spring Boot不支持druid配置,参数调优部分的配置不会直接生效,需要配置datasource bean,从application.properties中读取值来装配datasource bean,新增DruidConfig.java配置文件:
DruidConfig.java代码如下,通过@value注解读取配置文件中的值
package com.qikegu.demo.config;
import java.sql.SQLException;
import javax.sql.DataSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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;
@Configuration
public class DruidConfig {
private Logger logger = LoggerFactory.getLogger(DruidConfig.class);
@Value("${spring.datasource.url}")
private String dbUrl;
@Value("${spring.datasource.username}")
private String username;
@Value("${spring.datasource.password}")
private String password;
@Value("${spring.datasource.driver-class-name}")
private String driverClassName;
@Value("${spring.datasource.initial-size}")
private int initialSize;
@Value("${spring.datasource.min-idle}")
private int minIdle;
@Value("${spring.datasource.max-active}")
private int maxActive;
@Value("${spring.datasource.max-wait}")
private int maxWait;
@Value("${spring.datasource.time-between-eviction-runs-millis}")
private int timeBetweenEvictionRunsMillis;
@Value("${spring.datasource.min-evictable-idle-time-millis}")
private int minEvictableIdleTimeMillis;
// @Value("${spring.datasource.validation-query}")
// private String validationQuery;
@Value("${spring.datasource.test-while-idle}")
private boolean testWhileIdle;
@Value("${spring.datasource.test-on-borrow}")
private boolean testOnBorrow;
@Value("${spring.datasource.test-on-return}")
private boolean testOnReturn;
@Value("${spring.datasource.pool-prepared-statements}")
private boolean poolPreparedStatements;
@Value("${spring.datasource.max-pool-prepared-statement-per-connection-size}")
private int maxPoolPreparedStatementPerConnectionSize;
@Value("${spring.datasource.filters}")
private String filters;
// @Value("${spring.datasource.connection-properties}")
// private String connectionProperties;
@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);
try {
datasource.setFilters(filters);
} catch (SQLException e) {
logger.error("druid configuration initialization filter", e);
}
// datasource.setConnectionProperties(connectionProperties);
return datasource;
}
}
访问数据库
添加代码验证数据库是否正常连接,添加文件:HelloController.java
HelloController.java的代码
package com.qikegu.demo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HelloController {
@Autowired
JdbcTemplate jdbcTemplate;
@RequestMapping(value="/hello", method=RequestMethod.GET)
public String index() {
String sql = "SELECT mobile FROM user WHERE id = ?";
// 通过jdbcTemplate查询数据库
String mobile = (String)jdbcTemplate.queryForObject(
sql, new Object[] { 1 }, String.class);
return "Hello " + mobile;
}
}
我们使用spring的JdbcTemplate(这正是我们在前面引入spring jdbc依赖的原因),比使用原始的jdbc接口方便。
运行
项目的右键菜单,选择:run as -> spring boot app
运行程序(不清楚怎么运行可参考: spring boot hello world (restful接口)例子),使用浏览器访问,输出从数据库中读取的用户手机号
使用druid的监控功能
druid的监控功能,可以通过网址:http://localhost:8096/druid/index.html 查看。
查看DataSource页面,可以看到我们的配置确实生效了:
总结
本文介绍了怎样在spring boot项目中集成druid连接池,使用JdbcTemplate访问数据库,验证数据库连接成功。