SSM 框架学习 (MyBatis篇)
二、MyBatis SQL 映射文件的配置
条件模糊查询表信息
1、单个参数
// UserMapper.java
public interface UserMapper {
public List<User> getUserListByUserName(String userName);
}
// UserMapper.xml
<!--根据用户名称查询用户列表(模糊查询) concat 连接字符串 resultType 返回类型, paramenterType传参类型-->
<select id="getUserListByUserName" resultType="User"
parameterType="String">
select * from smbms_user where userName like CONCAT
('%',#{userName},'%')
</select>
2、(传入参数:对象)
// UserMapper.java
public interface UserMapper {
public List<User> getUserListByUser(User user);
}
// UserMapper.xml
<!-- 查询用户列表(参数:对象入参) -->
<select id="getUserListByUser" resultType="User" parameterType="User">
select * from smbms_user where userName like CONCAT
('%',#{userName},'%') and userRole = #{userRole}
</select>
3、(传入参数:Map)
// UserMapper.java
public interface UserMapper {
public List<User> getUserListByMap(Map<String, String> userMap);
}
// UserMapper.xml
<!-- 查询用户列表(参数:Map) -->
<select id="getUserListByMap" resultType="User" parameterType="Map">
select * from smbms_user where userName like CONCAT
('%',#{uName},'%') and userRole = #{uRole}
</select>
4、resultMap使用
// UserMapper.xml
<!-- 当数据库中的字段信息与对象的属性不一致时需要通过resultMap来映射,即将不同表合并成一张 -->
<resultMap type="User" id="userList">
<result property="id" column="id" />
<result property="userCode" column="userCode" />
<result property="userName" column="userName" />
<result property="phone" column="phone" />
<result property="birthday" column="birthday" />
<result property="gender" column="gender" />
<result property="userRole" column="userRole" />
<result property="userRoleName" column="roleName" />
</resultMap>
<select id="getUserListByUser" resultMap="userList" parameterType="User">
select u.*,r.roleName from smbms_user u,smbms_role r
where u.userName like CONCAT ('%',#{userName},'%')
and u.userRole = #{userRole} and u.userRole = r.id
</select>
5、向数据库添加信息
// UserMapper.java
public interface UserMapper {
public int addUser(User user);
}
// UserMapper.xml
<!-- 增加新用户 -->
<insert id="addUser" parameterType="User">
insert into smbms_user
(userCode,userName,userPassword,gender,birthday,phone,
address,userRole,createdBy,creationDate)
values (#{userCode}, #{userName}, #{userPassword},#{gender},#{birthday},
#{phone},#{address},#{userRole},#{createdBy},#{creationDate})
</insert>
6、更新数据库信息1
// UserMapper.java
public interface UserMapper {
public int modify(User user);
}
// UserMapper.xml
<!-- 修改用户信息 -->
<update id="modify" parameterType="User">
update smbms_user set
userCode=#{userCode},userName=#{userName},userPassword=#{userPassword},
gender=#{gender},birthday=#{birthday},phone=#{phone},address=#{address},
userRole=#{userRole},modifyBy=#{modifyBy},modifyDate=#{modifyDate}
where id = #{id}
</update>
7、更新数据库信息2
// UserMapper.java
public interface UserMapper {
public int updatePwd(@Param("id")Integer id, @Param("userPassword")String pwd);
}
// UserMapper.xml
<!-- 修改当前用户密码 -->
<update id="updatePwd">
update smbms_user set userPassword=#{userPassword} where id = #{id}
</update>
8、删除数据
// UserMapper.java
public interface UserMapper {
public int deleteUserById(@Param("id")Integer delId);
}
// UserMapper.xml
<!-- 根据用户id删除用户信息 -->
<delete id="deleteUserById">
delete from smbms_user where id = #{id}
</delete>
9、resultMap > association 使用
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// UserMapper.java
public interface UserMapper {
public List<User> getUserListByRoleId(@Param("userRole")Integer roleId);
}
// User.java
public class User {
// association
private Role role; // 用户角色
public Role getRole() {
return role;
}
public void setRole(Role role) {
this.role = role;
}
// association
}
// Role.java
public class Role {
private Integer id; // id
private String roleCode; // 角色编码
private String roleName; // 角色名称
...
//get{} set{}
}
// UserMapper.xml
<!-- 根据用户id获取用户列表 association start -->
<resultMap type="User" id="userRoleList">
<id property="id" column="id" />
<result property="userCode" column="userCode" />
<result property="userName" column="userName" />
<result property="userRole" column="userRole" />
<!-- javaType=Role 对应JavaBean名 | column 对应数据库查询结果集的字段 | property 对应JavaBean的属性-->
<association property="role" javaType="Role">
<id property="id" column="r_id" />
<result property="roleCode" column="roleCode" />
<result property="roleName" column="roleName" />
</association>
</resultMap>
<select id="getUserListByRoleId" parameterType="Integer"
resultMap="userRoleList">
select u.*,r.id as r_id,r.roleCode, r.roleName
from smbms_user u,smbms_role r
where u.userRole=#{userRole}
and u.userRole = r.id
</select>
<!-- 根据用户id获取用户列表 association end -->
10、resultMap > association使用2 (在第9步的基础上修改)
// UserMapper.java
public interface UserMapper {
public List<User> getUserListByRoleId2(@Param("userRole")Integer roleId);
}
// UserMapper.xml
<!-- 根据用户id获取用户列表2 association start -->
<resultMap type="User" id="userRoleList2">
<id property="id" column="id" />
<result property="userCode" column="userCode" />
<result property="userName" column="userName" />
<result property="userRole" column="userRole" />
<association property="role" javaType="Role" resultMap="roleResult" />
</resultMap>
<resultMap type="Role" id="roleResult">
<id property="id" column="r_id" />
<result property="roleCode" column="roleCode" />
<result property="roleName" column="roleName" />
</resultMap>
<select id="getUserListByRoleId2" parameterType="Integer"
resultMap="userRoleList2">
select u.*,r.id as r_id,r.roleCode, r.roleName
from smbms_user u,smbms_role r
where u.userRole=#{userRole}
and u.userRole = r.id
</select>
<!-- 根据用户id获取用户列表2 association end -->
11、resultMap > collection使用1
// UserMapper.java
public interface UserMapper {
public List<User> getAddressListByUserId(@Param("id")Integer userId);
}
// User.java
public class User {
// collection
private List<Address> addressList;
public List<Address> getAddressList() {
return addressList;
}
public void setAddressList(List<Address> addressList) {
this.addressList = addressList;
}
// collection
}
// Role.java
public class Address {
...
//get{} set{}
}
// UserMapper.xml
<!-- 获取指定用户的地址列表(user表-address表: 1对多) collection start -->
<resultMap type="User" id="userAddressList">
<id property="id" column="id" />
<result property="userCode" column="userCode" />
<result property="userName" column="userName" />
<!-- ofType 对应JavaBean -->
<collection property="addressList" ofType="Address">
<id property="id" column="a_id" />
<result property="postCode" column="postCode" />
<result property="tel" column="tel" />
<result property="contact" column="contact" />
<result property="addressDesc" column="addressDesc" />
</collection>
</resultMap>
<select id="getAddressListByUserId" parameterType="Integer"
resultMap="userAddressList">
select u.*, a.id as a_id, a.contact, a.addressDesc, a.tel, a.postCode
from smbms_user u, smbms_address a
where u.id=a.userId and u.id=#{id}
</select>
<!-- 获取指定用户的地址列表(user表-address表: 1对多) collection end -->
12、resultMap > collection使用2 (在第11步的基础上修改)
// UserMapper.java
public interface UserMapper {
public List<User> getAddressListByUserId2(@Param("id")Integer userId);
}
// UserMapper.xml
<!-- 获取指定用户的地址列表2(user表-address表: 1对多) collection start -->
<resultMap type="User" id="userAddressList2">
<id property="id" column="id" />
<result property="userCode" column="userCode" />
<result property="userName" column="userName" />
<!-- ofType 对应JavaBean -->
<collection property="addressList" ofType="Address" resultMap="addressResult"/>
</resultMap>
<resultMap type="Address" id="addressResult">
<id property="id" column="a_id" />
<result property="postCode" column="postCode" />
<result property="tel" column="tel" />
<result property="contact" column="contact" />
<result property="addressDesc" column="addressDesc" />
</resultMap>
<select id="getAddressListByUserId2" parameterType="Integer"
resultMap="userAddressList2">
select u.*, a.id as a_id, a.contact, a.addressDesc, a.tel, a.postCode
from smbms_user u, smbms_address a
where u.id=a.userId and u.id=#{id}
</select>
<!-- 获取指定用户的地址列表2(user表-address表: 1对多) collection end -->
13、resultMap自动映射的匹配 级别
// mybatis-config.xml
<settings>
<setting name="logImpl" value="LOG4J"/>
<!-- 设置resultMap的自动映射级别
NONE(禁止自动匹配,无法自动匹配JavaBean属性)
PARTIAL(默认:局部)
FULL(全部映射,除了匹配resultMap属性还有JavaBean的全部属性)
-->
<!-- <setting name="autoMappingBehavior" value="NONE"/> -->
<!-- <setting name="autoMappingBehavior" value="PARTIAL"/> -->
<!-- <setting name="autoMappingBehavior" value="FULL"/> -->
</settings>
@Author 瞌睡虫
@mybatis-3.2.2
@Database: mysql 5.7.15
@Tool: MyEclipse