Spring boot Mybatis依赖注入配置

使用Spring boot Mybatis进行依赖注入配置时，遇到很多问题，希望在applicationContext.xml中配置所有的依赖注入关系，倒腾了几次，才基本搞清楚：需要配置所有的类型，包括dataSource、sqlSessionFactory，并且需要为Mapper接口进行配置，还需要设置从项目配置文件中读取数据库的配置信息。

首先是dataSource的配置：

    <context:component-scan base-package="com.example" />
    <bean id="dataSource"
          class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${spring.datasource.driver-class-name}" />
        <property name="url" value="${spring.datasource.url}" />
        <property name="username" value="${spring.datasource.username}" />
        <property name="password" value="${spring.datasource.password}" />
    </bean>
    <context:property-placeholder location="application.properties" />

这里context是为了从配置文件application.properties中读取数据库的设置。这需要在xml文件中声明相应的名称空间：

<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.xsd"
>

然后是sqlSessionFactory:

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
    </bean>

接下来是定义的Mapper接口，在代码中的定义如下：

package com.example;

import cn.jiagoushi.poemgame.poemservice.shared.PoemLine;
import cn.jiagoushi.poemgame.poemservice.shared.Poet;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

/**
 *
 * @author zhenl
 */
@Mapper
public interface PoemLineMapper {
    @Select("SELECT * FROM POEMLINE")
    List<PoemLine> getAll();
    
    @Select("SELECT * FROM POEMLINE WHERE LineContent=#{line} ")
    PoemLine GetPoemLine(@Param("line") String line);
    
    @Select("SELECT * FROM POEMLINE WHERE PoemId=#{poemId} ")
    List<PoemLine> GetPoemLineByPoemId(@Param("poemId") String poemId) ;
    
    @Select("SELECT * FROM POET WHERE Name=#{name} ")
    Poet GetPoetByName(@Param("name") String name);
}

这个接口在配置中对应的class是"org.mybatis.spring.mapper.MapperFactoryBean" ，定义如下：

    <bean id="mapperbean" class="org.mybatis.spring.mapper.MapperFactoryBean" >
        <property name="mapperInterface" value="com.example.PoemLineMapper" />
        <property name="sqlSessionFactory" ref="sqlSessionFactory" />
    </bean>

接下来就可以定义使用这个接口的bean:

    <bean id="duishicheckanswerbean" class="cn.jiagoushi.poemgame.domain.service.duishi.DuishiCheckAnswer">
        <constructor-arg ref="mypoemservicebean"/>
    </bean>