MyBatis内置了数据源的支持,如:
<environments default="development"> <environment id="development"> <transactionManager type="JDBC" /> <dataSource type="POOLED"> <property name="driver" value="${jdbc.driverClassName}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> </dataSource> </environment>
type为POOLED的数据源是MyBatis内置的数据源类型(它是一个类型别名)。POOLED对应的数据库连接池工厂是org.apache.ibatis.datasource.pooled.PooledDataSourceFactory,它必须实现接口 org.apache.ibatis.datasource.DataSourceFactory
package org.apache.ibatis.datasource.pooled; import org.apache.ibatis.datasource.unpooled.UnpooledDataSourceFactory; public class PooledDataSourceFactory extends UnpooledDataSourceFactory { public PooledDataSourceFactory() { this.dataSource = new PooledDataSource(); } }
目前有各种各样的数据源实现,如果在项目中要使用第三方的数据源,如何将它配置到MyBatis中呢?通过实现 org.apache.ibatis.datasource.DataSourceFactory将数据源集成到MyBatis中。本文以Druid数据源为例。
实现DataSourceFactory接口
package com.mybatis3.datasource; import com.alibaba.druid.pool.DruidDataSource; import org.apache.ibatis.datasource.DataSourceFactory; import javax.sql.DataSource; import java.sql.SQLException; import java.util.Properties; public class DruidDataSourceFactory implements DataSourceFactory { private Properties props; @Override public void setProperties(Properties props) { this.props = props; } @Override public DataSource getDataSource() { DruidDataSource dds = new DruidDataSource(); dds.setUrl(this.props.getProperty("url")); dds.setPassword(this.props.getProperty("password")); dds.setUsername(this.props.getProperty("username")); dds.setDriverClassName("com.mysql.jdbc.Driver"); //其他配置可以根据MyBatis主配置文件进行配置 try { dds.init(); } catch (SQLException e) { e.printStackTrace(); } return dds; } }
主配置文件配置:
1. DRUID类型别名:
<typeAliases> <typeAlias type="com.mybatis3.datasource.DruidDataSourceFactory" alias="DRUID"/> </typeAliases>
2. 数据源配置
<environments default="development"> <environment id="development"> <transactionManager type="JDBC" /> <dataSource type="DRUID"> <property name="url" value="jdbc:mysql://127.0.0.1:3306/test" /> <property name="username" value="root" /> <property name="password" value="root" /> <property name="maxActive" value="20" /> <property name="initialSize" value="1" /> <property name="maxWait" value="60000" /> <property name="minIdle" value="1" /> <property name="timeBetweenEvictionRunsMillis" value="3000" /> <property name="minEvictableIdleTimeMillis" value="300000" /> <property name="validationQuery" value="SELECT 'x' FROM DUAL" /> <property name="testWhileIdle" value="true" /> <property name="testOnBorrow" value="false" /> <property name="testOnReturn" value="false" /> <!-- mysql 不支持 poolPreparedStatements--> <!--<property name="poolPreparedStatements" value="true" />--> <!--<property name="maxPoolPreparedStatementPerConnectionSize" value="20" />--> <!-- 开启Druid的监控统计功能 --> <property name="filters" value="stat" /> </dataSource> </environment>