mybatis使用全注解的方式案例（包含一对多关系映射）

前面我写过ssh：ssh(Spring+Spring mvc+hibernate)简单增删改查案例 和ssm：ssm(Spring+Spring mvc+mybatis)的案例，需要了解的可以去看看，今天我写了一下ssm(spring+springmvc+mybatis)全注解的方式又重新写了一遍两表增删改查的案例，其中别的地方都一样，就是有几个文件不一样，
1.其中:
mybatis-config.xml中：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
  PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<settings>
     <!-- 打印查询语句 -->
     <setting name="logImpl" value="STDOUT_LOGGING" />
</settings>
<typeAliases>
  <typeAlias alias="Emp" type="org.entity.Emp"/>
  <typeAlias alias="Dept" type="org.entity.Dept"/>
</typeAliases>
  <mappers>
    <mapper class="org.dao.IEmpMapper"/>
     <mapper class="org.dao.IDeptMapper"/>
  </mappers>
</configuration>

注意看， <mapper class="org.dao.IEmpMapper"/>，mapper后面是class,不是resource,一定要注意
2.还有：我们不需要EmpMapper.xml和DeptMapper.xml文件，直接删掉就可以了
3.修改我们的IEmpMapper接口为：

package org.dao;

import java.util.List;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.One;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import org.entity.Emp;

public interface IEmpMapper {
	//根据编号删除.
	@Delete("delete from emp where eid = #{eid} ")
    int deleteByPrimaryKey(Integer eid);
    //添加
    @Insert("insert into emp (eid, ename, eage,  edate, did) " +
			"values (#{eid,jdbcType=INTEGER}," +
			" #{ename,jdbcType=VARCHAR}, " +
			"#{eage,jdbcType=INTEGER},  " +
			"#{edate,jdbcType=TIMESTAMP}," +
			" #{did,jdbcType=INTEGER})")
    int insert(Emp record);
    //根据编号查询
    @Select("select * from emp where eid = #{eid}")
    @Results({
    	@Result(id=true,property="eid",column="eid"),
    	@Result(property="ename",column="ename"),
    	@Result(property="eage",column="eage"),
    	@Result(property="dept",column="did",javaType=org.entity.Dept.class,
    	one=@One(select="org.dao.IDeptMapper.selectByPrimaryKey"))
    })
    Emp selectByPrimaryKey(Integer eid);
    //修改
    @Update("pdate emp " +
    		" set ename = #{ename,jdbcType=VARCHAR}, " +
    		" eage = #{eage,jdbcType=INTEGER}, " +
    		" edate = #{edate,jdbcType=TIMESTAMP}, " +
    		"  did = #{did,jdbcType=INTEGER} " +
    		"where eid = #{eid,jdbcType=INTEGER}")
    int updateByPrimaryKey(Emp record);
    //查询全部
    @Select("select * from emp")
    @Results({
    	@Result(id=true,property="eid",column="eid"),
    	@Result(property="ename",column="ename"),
    	@Result(property="eage",column="eage"),
    	@Result(property="dept",column="did",javaType=org.entity.Dept.class,
    	one=@One(select="org.dao.IDeptMapper.selectByPrimaryKey"))
    })
    List<Emp> findEmpAll();
    
    //根据部门编号查询员工信息
    @Select("select * from emp where did = #{dids}")
    @Results({
    	@Result(id=true,property="eid",column="eid"),
    	@Result(property="ename",column="ename"),
    	@Result(property="eage",column="eage"),
    	@Result(property="dept",column="did",javaType=org.entity.Dept.class,
    	one=@One(select="org.dao.IDeptMapper.selectByPrimaryKey"))
    })
    List<Emp> findEmpByDept(int did);
    
}

4.修改我们的IDeptMapper接口为：

package org.dao;

import java.util.List;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Many;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import org.entity.Dept;

public interface IDeptMapper {
	@Delete("delete from dept where id = #{id}")
    int deleteByPrimaryKey(Integer id);

	@Insert("insert into dept (id, name, loc )" +
			" values (#{id,jdbcType=INTEGER}, " +
			"#{name,jdbcType=VARCHAR}, " +
			"#{loc,jdbcType=VARCHAR})")
    int insert(Dept record);

	@Select("select * from dept where id  = #{id}")
    @Results({
        @Result(id=true,property="id",column="id"),
        @Result(property="name",column="name"),
        @Result(property="loc",column="loc"),
        @Result(property="empList",column="id",javaType=List.class,
        many=@Many(select="org.dao.IEmpMapper.findEmpByDept"))
    })
    Dept selectByPrimaryKey(Integer id);

    @Update("update dept " +
			"set name = #{name,jdbcType=VARCHAR}, " +
			" loc = #{loc,jdbcType=VARCHAR} " +
			"where id = #{id,jdbcType=INTEGER}")
    int updateByPrimaryKey(Dept record);
    
    @Select("select * from dept")
    List<Dept> findDeptAll();
}

然后就可以正常的主外键关联，包括查询显示，如图：
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需要注意的是主外键映射，我总结了以下的方法，大家可以进行看一下：

一：
@Select("select * from dept where id  = #{id}")
    @Results({
        @Result(id=true,property="id",column="id"),
        @Result(property="name",column="name"),
        @Result(property="loc",column="loc"),
        @Result(property="实体类里面的属性",
		column="id",javaType=List.class,
        many=@Many(select="多方的接口.根据一方的编号查询多方的集合"))
    })
    Dept selectByPrimaryKey(Integer id);
 

多：
  //根据编号查询
    @Select("select * from emp where eid = #{eid}")
    @Results({
    	@Result(id=true,property="eid",column="eid"),
    	@Result(property="ename",column="ename"),
    	@Result(property="eage",column="eage"),
    	 @Result(property="实体中的对象",column="外键列",javaType=一方类.class,
        one=@One(select="一方接口.根据一方编号查询信息"))
    })
    Emp selectByPrimaryKey(Integer eid);

	
	 //查询全部
    @Select("select * from emp")
    @Results({
    	@Result(id=true,property="eid",column="eid"),
    	@Result(property="ename",column="ename"),
    	@Result(property="eage",column="eage"),
    	@Result(property="实体中的对象",column="外键列",javaType=一方类.class,
        one=@One(select="一方接口.根据一方编号查询信息"))
    })
    List<Emp> findEmpAll();
	
	//根据部门编号查询员工信息
    @Select("select * from emp where did = #{dids}")
    @Results({
    	@Result(id=true,property="eid",column="eid"),
    	@Result(property="ename",column="ename"),
    	@Result(property="eage",column="eage"),
    	@Result(property="实体中的对象",column="外键列",javaType=一方类.class,
        one=@One(select="一方接口.根据一方编号查询信息"))
    })
    List<Emp> findEmpByDept(int did);

按照这个方法配置保证阿弥陀佛了！！！
下面就是源码：
控制器：
DeptController
EmpController
Dao层：
IDeptMapper
IEmpMapper
DaoImpl层：
DeptMapperImpl
EmpMapperImpl
实体类层：
Dept
Emp
Service层：
IDeptService
IEmpService
ServiceImpl层：
DeptServiceImpl
EmpServiceImpl
配置文件：
applicationContext-servlet.xml
applicationContext.xml
mybatis-config.xml
web.xml
前台页面：
index.jsp
saveDept.jsp
saveEmp.jsp
showDept.jsp
showEmp.jsp
updateDept.jsp
updateEmp.jsp