Springboot+mybatis+druid的整合

最近的公司项目后端用到了Springboot框架，把阿里的druid作为数据源，采用mybatis+druid的方式，本人之前也是在这里踩了很多坑，因此感觉有必要出个博客来记录一下。

首先，用druid最为数据源的好处就不多说了，灵活动态切换数据库是小case，更重要的是提供了健全的数据库监控机制和页面（号称目前最好的数据库连接池可不是简单说说），开始进入正题。

首先创建Springboot项目，这里就不多说了，可以点击这里看怎么创建Springboot项目，接着，在pom文件中引入mybatis、mysql和druid所需要的依赖，如下

<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.20</version> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.2.1</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.9</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency>

然后再在项目中分别创建model，dao，service，controller，这里就不多说了，各位应该都会，创建好后如下

需要注意的是，dao要写成接口形式，并且注解为@Mapper

@Mapper public interface SysUserDao { public SysUser getUserById(String id); }

service和controller的注解还是和原来的一样，service用@Service，controller用@RestController，接着就是编写Mapper.xml配置文件，可以不写mapper.xml配置文件直接在dao上写sql语句，实现零配置模式，但是个人不建议，毕竟实体类还是简单点好。mapper配置文件如下

<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.azhe.mybsql.dao.SysUserDao" > <resultMap id="BaseResultMap" type="com.azhe.mybsql.model.SysUser" > <id column="ID" property="id" jdbcType="VARCHAR" /> <result column="USER_NAME" property="userName" jdbcType="VARCHAR" /> <result column="PASSWORD" property="password" jdbcType="VARCHAR" /> </resultMap> <select id="getUserById" parameterType="java.lang.String" resultMap="BaseResultMap"> select * from sys_user where id = #{id, jdbcType=VARCHAR} </select> </mapper>

其中的查询语句  （ <select id="getUserById‘’ ......） id必须和dao的方法名一致，并且指定的参数类型和返回类型也要一致，才能映射成功。

配置文件放置于resource路径下即可，本人就放在这个位置

然后在applicatin.yml中配置数据mapper文件的位置

mybatis: mapper-locations: classpath:mybatis/*.xml

然后再在配置文件中编写数据源和设置数据库连接池

spring: datasource: url: jdbc:mysql://localhost:3306/shc-accounts?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC username: root password: 1003 driver-class-name: com.mysql.jdbc.Driver platform: mysql # 使用druid数据源 type: com.alibaba.druid.pool.DruidDataSource # 初始化连接池大小 initialSize: 10 # 连接池最少 minIdle: 3 # 连接池最多 maxActive: 20 # 获取连接等待超时 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: 30000 validationQuery: select 'x' 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 filters: stat,wall,slf4j # 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

其中的commun_forum是事先已经创建好的数据库，这里建议大家在配置数据库url时，后边加上 ?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC ,否则有可能会报错，一直循环的连接失败、连接失败，具体原因下次有机会再说。

最后在项目中加上druid的管理配置文件，用java文件作为配置文件即可，如下

package com.azhe.config; import com.alibaba.druid.pool.DruidDataSource; import com.alibaba.druid.support.http.StatViewServlet; import com.alibaba.druid.support.http.WebStatFilter; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.boot.context.properties.ConfigurationProperties; 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; import org.springframework.context.annotation.Primary; import javax.sql.DataSource; import java.sql.SQLException; /** * Linzr */ @Configuration public class DruidConfiguration { private static final Logger logger = LoggerFactory.getLogger(DruidConfiguration.class); private static final String DB_PREFIX = "spring.datasource"; @Bean public ServletRegistrationBean druidServlet() { logger.info("init Druid Servlet Configuration "); ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*"); // IP白名单 servletRegistrationBean.addInitParameter("allow", "192.168.2.25,127.0.0.1"); // IP黑名单(共同存在时，deny优先于allow) servletRegistrationBean.addInitParameter("deny", "192.168.1.100"); //控制台管理用户 servletRegistrationBean.addInitParameter("loginUsername", "admin"); servletRegistrationBean.addInitParameter("loginPassword", "5555"); //是否能够重置数据 禁用HTML页面上的“Reset All”功能 servletRegistrationBean.addInitParameter("resetEnable", "false"); return servletRegistrationBean; } @Bean public FilterRegistrationBean filterRegistrationBean() { FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter()); filterRegistrationBean.addUrlPatterns("/*"); filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*"); return filterRegistrationBean; } //解决 spring.datasource.filters=stat,wall,log4j 无法正常注册进去 @ConfigurationProperties(prefix = DB_PREFIX) class IDataSourceProperties { private String url; private String username; private String password; private String driverClassName; private int initialSize; private int minIdle; private int maxActive; private int maxWait; private int timeBetweenEvictionRunsMillis; private int minEvictableIdleTimeMillis; private String validationQuery; private boolean testWhileIdle; private boolean testOnBorrow; private boolean testOnReturn; private boolean poolPreparedStatements; private int maxPoolPreparedStatementPerConnectionSize; private String filters; 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(url); 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) { System.err.println("druid configuration initialization filter: " + e); } datasource.setConnectionProperties(connectionProperties); return datasource; } public String getUrl() { return url; } public void setUrl(String url) { this.url = url; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public String getDriverClassName() { return driverClassName; } public void setDriverClassName(String driverClassName) { this.driverClassName = driverClassName; } public int getInitialSize() { return initialSize; } public void setInitialSize(int initialSize) { this.initialSize = initialSize; } public int getMinIdle() { return minIdle; } public void setMinIdle(int minIdle) { this.minIdle = minIdle; } public int getMaxActive() { return maxActive; } public void setMaxActive(int maxActive) { this.maxActive = maxActive; } public int getMaxWait() { return maxWait; } public void setMaxWait(int maxWait) { this.maxWait = maxWait; } public int getTimeBetweenEvictionRunsMillis() { return timeBetweenEvictionRunsMillis; } public void setTimeBetweenEvictionRunsMillis(int timeBetweenEvictionRunsMillis) { this.timeBetweenEvictionRunsMillis = timeBetweenEvictionRunsMillis; } public int getMinEvictableIdleTimeMillis() { return minEvictableIdleTimeMillis; } public void setMinEvictableIdleTimeMillis(int minEvictableIdleTimeMillis) { this.minEvictableIdleTimeMillis = minEvictableIdleTimeMillis; } public String getValidationQuery() { return validationQuery; } public void setValidationQuery(String validationQuery) { this.validationQuery = validationQuery; } public boolean isTestWhileIdle() { return testWhileIdle; } public void setTestWhileIdle(boolean testWhileIdle) { this.testWhileIdle = testWhileIdle; } public boolean isTestOnBorrow() { return testOnBorrow; } public void setTestOnBorrow(boolean testOnBorrow) { this.testOnBorrow = testOnBorrow; } public boolean isTestOnReturn() { return testOnReturn; } public void setTestOnReturn(boolean testOnReturn) { this.testOnReturn = testOnReturn; } public boolean isPoolPreparedStatements() { return poolPreparedStatements; } public void setPoolPreparedStatements(boolean poolPreparedStatements) { this.poolPreparedStatements = poolPreparedStatements; } public int getMaxPoolPreparedStatementPerConnectionSize() { return maxPoolPreparedStatementPerConnectionSize; } public void setMaxPoolPreparedStatementPerConnectionSize(int maxPoolPreparedStatementPerConnectionSize) { this.maxPoolPreparedStatementPerConnectionSize = maxPoolPreparedStatementPerConnectionSize; } public String getFilters() { return filters; } public void setFilters(String filters) { this.filters = filters; } public String getConnectionProperties() { return connectionProperties; } public void setConnectionProperties(String connectionProperties) { this.connectionProperties = connectionProperties; } } }

这里要注意的是，要加上@Bean注解，Spring启动时候才会进行初始化并进行管理，然后就好了，整体的目录大概这样

接着，启动项目，也就是执行Applicatin.java中的main方法，启动成功后，和平时一样打开浏览器输入controller的映射地址去访问即可得到数据

然后将controller所映射的那段地址段换成druid，继续访问druid做带来的访问监控页面

然后输入账号密码，也就是前边的druid配置文件 DruidConfiguration  中所指定的账号密码

servletRegistrationBean.addInitParameter("loginUsername", "admin"); servletRegistrationBean.addInitParameter("loginPassword", "5555");

输入即可登录

至此，整合完毕