mybatis spring 整合的一点问题
----------spring配置文件----------------
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver">
</property>
<property name="url" value="jdbc:mysql://localhost:3306/test" />
<property name="username" value="root"></property>
<property name="password" value="root"></property>
</bean>
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="myDataSource" />
<property name="configLocation" value="classpath:mybatis.xml" />
</bean>
<bean id="mapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
<property name="mapperInterface" value="com.insigma.mappers.Mapper" />
<property name="sqlSessionFactory" ref="sqlSessionFactory" />
</bean>
<bean id="smapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
<property name="mapperInterface" value="com.insigma.mappers.SMapper" />
<property name="sqlSessionFactory" ref="sqlSessionFactory" />
</bean>
<bean id="test" class="com.insigma.test.Tes">
<property name="mapper" ref="mapper">
</property>
<property name="id" value="12"></property>
</bean>
</beans>
----------mybatis配置文件----------------
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//ibatis.apache.org//DTD Config 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-config.dtd">
<configuration>
<typeAliases>
<typeAlias type="com.insigma.model.Student" alias="student" />
</typeAliases>
<mappers>
<mapper resource="com/insigma/mappers/Mapper.xml" />
<mapper resource="com/insigma/mappers/SMapper.xml" />
</mappers>
</configuration>
----------mapper配置文件----------------
<?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.insigma.mappers.Mapper">
<select id="getAll" resultType="student">
select * from student2
</select>
</mapper>
----------mapper接口----------------
package com.insigma.mappers;
import java.util.List;
import org.springframework.stereotype.Component;
import com.insigma.model.Student;
public interface Mapper {
public List<Student> getAll();
}
----------Student 类----------------
package com.insigma.model;
public class Student {
private int id;
private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
----------测试代码----------------
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring.xml");
System.out.println(context.getBean("myDataSource"));
System.out.println(context.getBean("sqlSessionFactory"));
System.out.println(context.getBean("mapper"));
System.out.println(context.getBean("test"));
}
----------测试结果----------------
org.apache.commons.dbcp.BasicDataSource@19e8f17
org.apache.ibatis.session.defaults.DefaultSqlSessionFactory@c44b88
null
com.insigma.test.Tes@17e121c
----------问题----------------
所有配置都好像没错 为什么System.out.println(context.getBean("mapper"))输出null ??? 在线求解
[解决办法]
还真是这样,我用我以前写的例子,这么操作就会出错。
但是获取出来直接使用或者注入到其他的bean内,都没问题。
感觉mapper并没有被实例化！
别在这里纠缠了。我的代码片段如下：
ApplicationContext context = new ClassPathXmlApplicationContext(new String[] { "spring.xml" });
BeanFactory factory = (BeanFactory) context;
IMybatisDao dao = (IMybatisDao) factory.getBean("mybatisDao");
//下面这行的方法可以正常执行
System.out.println(dao.selectOne("20110101"));
//这里就是打印不出来，抛空指针异常
System.out.println(dao);
