<!-- assocation 一对一映射 -->
<!--mybatis生成器中的代码 -->
<resultMap id="userRoleMap2" type="com.mybatis.demo.SysUser">
<id column="id" jdbcType="BIGINT" property="id" />
<result column="user_name" jdbcType="VARCHAR" property="userName" />
<result column="user_password" jdbcType="VARCHAR" property="userPassword" />
<result column="user_email" jdbcType="VARCHAR" property="userEmail" />
<result column="user_info" jdbcType="VARCHAR" property="userInfo" />
<result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
</resultMap>
<resultMap type="com.mybatis.demo.SysUser" id="userRoleMap"
extends="userRoleMap2">
<association property="role" columnPrefix="role_"
javaType="com.mybatis.demo.SysRole" resultMap="com.mybatis.demo.mapperSysRoleMapper.BaseResultMap">
</association>
</resultMap>
<select id="selectUserAndRoleId3" resultMap="userRoleMap3">
select u.id,
u.user_name userName,
u.user_password userPassword,
u.user_email
userEmail,
u.user_info userInfo,
u.head_img headImg,
u.create_time
createTime,
r.id role_id,
r.role_name role_name,
r.enabled
role_enabled,
r.create_by role_create_by,
r.create_time role_create_time
from sys_user u
inner join sys_user_role ur on u.id=ur.user_id
inner
join sys_role r on ur.role_id =r.id
where u.id=#{id}
</select>
<resultMap id="userRoleMap3" type="com.mybatis.demo.SysUser">
<id column="id" jdbcType="BIGINT" property="id" />
<result column="user_name" jdbcType="VARCHAR" property="userName" />
<result column="user_password" jdbcType="VARCHAR" property="userPassword" />
<result column="user_email" jdbcType="VARCHAR" property="userEmail" />
<result column="user_info" jdbcType="VARCHAR" property="userInfo" />
<result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
<collection property="roleList" columnPrefix="role_"
ofType="com.mybatis.demo.SysRole">
<id column="id" property="id" />
<result column="role_name" property="roleName" />
<result column="enabled" property="enabled" />
<result column="create_by" property="createBy" />
<result column="create_time" property="createTime" jdbcType="TIMESTAMP" />
</collection>
</resultMap>
自动生成器生成的代码，可以把resultmap复制到你的xml中，也可以直接写命名空间，给出xml代码如下
<?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.mybatis.demo.mapper.SysRoleMapper">
<resultMap id="BaseResultMap" type="com.mybatis.demo.SysRole">
<id column="id" jdbcType="BIGINT" property="id" />
<result column="role_name" jdbcType="VARCHAR" property="roleName" />
<result column="enabled" jdbcType="INTEGER" property="enabled" />
<result column="create_by" jdbcType="BIGINT" property="createBy" />
<result column="create_time" jdbcType="TIMESTAMP" property="createTime" />
</resultMap>
<sql id="Example_Where_Clause">
<where>
<foreach collection="oredCriteria" item="criteria" separator="or">
<if test="criteria.valid">
<trim prefix="(" prefixOverrides="and" suffix=")">
<foreach collection="criteria.criteria" item="criterion">
<choose>
<when test="criterion.noValue">
and ${criterion.condition}
</when>
<when test="criterion.singleValue">
and ${criterion.condition} #{criterion.value}
</when>
<when test="criterion.betweenValue">
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
</when>
<when test="criterion.listValue">
and ${criterion.condition}
<foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
#{listItem}
</foreach>
</when>
</choose>
</foreach>
</trim>
</if>
</foreach>
</where>
</sql>
<sql id="Update_By_Example_Where_Clause">
<where>
<foreach collection="example.oredCriteria" item="criteria" separator="or">
<if test="criteria.valid">
<trim prefix="(" prefixOverrides="and" suffix=")">
<foreach collection="criteria.criteria" item="criterion">
<choose>
<when test="criterion.noValue">
and ${criterion.condition}
</when>
<when test="criterion.singleValue">
and ${criterion.condition} #{criterion.value}
</when>
<when test="criterion.betweenValue">
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
</when>
<when test="criterion.listValue">
and ${criterion.condition}
<foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
#{listItem}
</foreach>
</when>
</choose>
</foreach>
</trim>
</if>
</foreach>
</where>
</sql>
<sql id="Base_Column_List">
id, role_name, enabled, create_by, create_time
</sql>
<select id="selectByExample" parameterType="com.mybatis.demo.mapper.SysRoleExample" resultMap="BaseResultMap">
select
<if test="distinct">
distinct
</if>
<include refid="Base_Column_List" />
from sys_role
<if test="_parameter != null">
<include refid="Example_Where_Clause" />
</if>
<if test="orderByClause != null">
order by ${orderByClause}
</if>
</select>
<select id="selectByPrimaryKey" parameterType="java.lang.Long" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from sys_role
where id = #{id,jdbcType=BIGINT}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Long">
delete from sys_role
where id = #{id,jdbcType=BIGINT}
</delete>
<delete id="deleteByExample" parameterType="com.mybatis.demo.mapper.SysRoleExample">
delete from sys_role
<if test="_parameter != null">
<include refid="Example_Where_Clause" />
</if>
</delete>
<insert id="insert" parameterType="com.mybatis.demo.SysRole">
insert into sys_role (id, role_name, enabled,
create_by, create_time)
values (#{id,jdbcType=BIGINT}, #{roleName,jdbcType=VARCHAR}, #{enabled,jdbcType=INTEGER},
#{createBy,jdbcType=BIGINT}, #{createTime,jdbcType=TIMESTAMP})
</insert>
<insert id="insertSelective" parameterType="com.mybatis.demo.SysRole">
insert into sys_role
<trim prefix="(" suffix=")" suffixOverrides=",">
<if test="id != null">
id,
</if>
<if test="roleName != null">
role_name,
</if>
<if test="enabled != null">
enabled,
</if>
<if test="createBy != null">
create_by,
</if>
<if test="createTime != null">
create_time,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides=",">
<if test="id != null">
#{id,jdbcType=BIGINT},
</if>
<if test="roleName != null">
#{roleName,jdbcType=VARCHAR},
</if>
<if test="enabled != null">
#{enabled,jdbcType=INTEGER},
</if>
<if test="createBy != null">
#{createBy,jdbcType=BIGINT},
</if>
<if test="createTime != null">
#{createTime,jdbcType=TIMESTAMP},
</if>
</trim>
</insert>
<select id="countByExample" parameterType="com.mybatis.demo.mapper.SysRoleExample" resultType="java.lang.Integer">
select count(*) from sys_role
<if test="_parameter != null">
<include refid="Example_Where_Clause" />
</if>
</select>
<update id="updateByExampleSelective" parameterType="map">
update sys_role
<set>
<if test="record.id != null">
id = #{record.id,jdbcType=BIGINT},
</if>
<if test="record.roleName != null">
role_name = #{record.roleName,jdbcType=VARCHAR},
</if>
<if test="record.enabled != null">
enabled = #{record.enabled,jdbcType=INTEGER},
</if>
<if test="record.createBy != null">
create_by = #{record.createBy,jdbcType=BIGINT},
</if>
<if test="record.createTime != null">
create_time = #{record.createTime,jdbcType=TIMESTAMP},
</if>
</set>
<if test="_parameter != null">
<include refid="Update_By_Example_Where_Clause" />
</if>
</update>
<update id="updateByExample" parameterType="map">
update sys_role
set id = #{record.id,jdbcType=BIGINT},
role_name = #{record.roleName,jdbcType=VARCHAR},
enabled = #{record.enabled,jdbcType=INTEGER},
create_by = #{record.createBy,jdbcType=BIGINT},
create_time = #{record.createTime,jdbcType=TIMESTAMP}
<if test="_parameter != null">
<include refid="Update_By_Example_Where_Clause" />
</if>
</update>
<update id="updateByPrimaryKeySelective" parameterType="com.mybatis.demo.SysRole">
update sys_role
<set>
<if test="roleName != null">
role_name = #{roleName,jdbcType=VARCHAR},
</if>
<if test="enabled != null">
enabled = #{enabled,jdbcType=INTEGER},
</if>
<if test="createBy != null">
create_by = #{createBy,jdbcType=BIGINT},
</if>
<if test="createTime != null">
create_time = #{createTime,jdbcType=TIMESTAMP},
</if>
</set>
where id = #{id,jdbcType=BIGINT}
</update>
<update id="updateByPrimaryKey" parameterType="com.mybatis.demo.SysRole">
update sys_role
set role_name = #{roleName,jdbcType=VARCHAR},
enabled = #{enabled,jdbcType=INTEGER},
create_by = #{createBy,jdbcType=BIGINT},
create_time = #{createTime,jdbcType=TIMESTAMP}
where id = #{id,jdbcType=BIGINT}
</update>
</mapper>
package com.mybatis.demo.mapper;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
public class SysRoleExample {
protected String orderByClause;
protected boolean distinct;
protected List<Criteria> oredCriteria;
public SysRoleExample() {
oredCriteria = new ArrayList<Criteria>();
}
public void setOrderByClause(String orderByClause) {
this.orderByClause = orderByClause;
}
public String getOrderByClause() {
return orderByClause;
}
public void setDistinct(boolean distinct) {
this.distinct = distinct;
}
public boolean isDistinct() {
return distinct;
}
public List<Criteria> getOredCriteria() {
return oredCriteria;
}
public void or(Criteria criteria) {
oredCriteria.add(criteria);
}
public Criteria or() {
Criteria criteria = createCriteriaInternal();
oredCriteria.add(criteria);
return criteria;
}
public Criteria createCriteria() {
Criteria criteria = createCriteriaInternal();
if (oredCriteria.size() == 0) {
oredCriteria.add(criteria);
}
return criteria;
}
protected Criteria createCriteriaInternal() {
Criteria criteria = new Criteria();
return criteria;
}
public void clear() {
oredCriteria.clear();
orderByClause = null;
distinct = false;
}
protected abstract static class GeneratedCriteria {
protected List<Criterion> criteria;
protected GeneratedCriteria() {
super();
criteria = new ArrayList<Criterion>();
}
public boolean isValid() {
return criteria.size() > 0;
}
public List<Criterion> getAllCriteria() {
return criteria;
}
public List<Criterion> getCriteria() {
return criteria;
}
protected void addCriterion(String condition) {
if (condition == null) {
throw new RuntimeException("Value for condition cannot be null");
}
criteria.add(new Criterion(condition));
}
protected void addCriterion(String condition, Object value, String property) {
if (value == null) {
throw new RuntimeException("Value for " + property + " cannot be null");
}
criteria.add(new Criterion(condition, value));
}
protected void addCriterion(String condition, Object value1, Object value2, String property) {
if (value1 == null || value2 == null) {
throw new RuntimeException("Between values for " + property + " cannot be null");
}
criteria.add(new Criterion(condition, value1, value2));
}
public Criteria andIdIsNull() {
addCriterion("id is null");
return (Criteria) this;
}
public Criteria andIdIsNotNull() {
addCriterion("id is not null");
return (Criteria) this;
}
public Criteria andIdEqualTo(Long value) {
addCriterion("id =", value, "id");
return (Criteria) this;
}
public Criteria andIdNotEqualTo(Long value) {
addCriterion("id <>", value, "id");
return (Criteria) this;
}
public Criteria andIdGreaterThan(Long value) {
addCriterion("id >", value, "id");
return (Criteria) this;
}
public Criteria andIdGreaterThanOrEqualTo(Long value) {
addCriterion("id >=", value, "id");
return (Criteria) this;
}
public Criteria andIdLessThan(Long value) {
addCriterion("id <", value, "id");
return (Criteria) this;
}
public Criteria andIdLessThanOrEqualTo(Long value) {
addCriterion("id <=", value, "id");
return (Criteria) this;
}
public Criteria andIdIn(List<Long> values) {
addCriterion("id in", values, "id");
return (Criteria) this;
}
public Criteria andIdNotIn(List<Long> values) {
addCriterion("id not in", values, "id");
return (Criteria) this;
}
public Criteria andIdBetween(Long value1, Long value2) {
addCriterion("id between", value1, value2, "id");
return (Criteria) this;
}
public Criteria andIdNotBetween(Long value1, Long value2) {
addCriterion("id not between", value1, value2, "id");
return (Criteria) this;
}
public Criteria andRoleNameIsNull() {
addCriterion("role_name is null");
return (Criteria) this;
}
public Criteria andRoleNameIsNotNull() {
addCriterion("role_name is not null");
return (Criteria) this;
}
public Criteria andRoleNameEqualTo(String value) {
addCriterion("role_name =", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameNotEqualTo(String value) {
addCriterion("role_name <>", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameGreaterThan(String value) {
addCriterion("role_name >", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameGreaterThanOrEqualTo(String value) {
addCriterion("role_name >=", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameLessThan(String value) {
addCriterion("role_name <", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameLessThanOrEqualTo(String value) {
addCriterion("role_name <=", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameLike(String value) {
addCriterion("role_name like", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameNotLike(String value) {
addCriterion("role_name not like", value, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameIn(List<String> values) {
addCriterion("role_name in", values, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameNotIn(List<String> values) {
addCriterion("role_name not in", values, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameBetween(String value1, String value2) {
addCriterion("role_name between", value1, value2, "roleName");
return (Criteria) this;
}
public Criteria andRoleNameNotBetween(String value1, String value2) {
addCriterion("role_name not between", value1, value2, "roleName");
return (Criteria) this;
}
public Criteria andEnabledIsNull() {
addCriterion("enabled is null");
return (Criteria) this;
}
public Criteria andEnabledIsNotNull() {
addCriterion("enabled is not null");
return (Criteria) this;
}
public Criteria andEnabledEqualTo(Integer value) {
addCriterion("enabled =", value, "enabled");
return (Criteria) this;
}
public Criteria andEnabledNotEqualTo(Integer value) {
addCriterion("enabled <>", value, "enabled");
return (Criteria) this;
}
public Criteria andEnabledGreaterThan(Integer value) {
addCriterion("enabled >", value, "enabled");
return (Criteria) this;
}
public Criteria andEnabledGreaterThanOrEqualTo(Integer value) {
addCriterion("enabled >=", value, "enabled");
return (Criteria) this;
}
public Criteria andEnabledLessThan(Integer value) {
addCriterion("enabled <", value, "enabled");
return (Criteria) this;
}
public Criteria andEnabledLessThanOrEqualTo(Integer value) {
addCriterion("enabled <=", value, "enabled");
return (Criteria) this;
}
public Criteria andEnabledIn(List<Integer> values) {
addCriterion("enabled in", values, "enabled");
return (Criteria) this;
}
public Criteria andEnabledNotIn(List<Integer> values) {
addCriterion("enabled not in", values, "enabled");
return (Criteria) this;
}
public Criteria andEnabledBetween(Integer value1, Integer value2) {
addCriterion("enabled between", value1, value2, "enabled");
return (Criteria) this;
}
public Criteria andEnabledNotBetween(Integer value1, Integer value2) {
addCriterion("enabled not between", value1, value2, "enabled");
return (Criteria) this;
}
public Criteria andCreateByIsNull() {
addCriterion("create_by is null");
return (Criteria) this;
}
public Criteria andCreateByIsNotNull() {
addCriterion("create_by is not null");
return (Criteria) this;
}
public Criteria andCreateByEqualTo(Long value) {
addCriterion("create_by =", value, "createBy");
return (Criteria) this;
}
public Criteria andCreateByNotEqualTo(Long value) {
addCriterion("create_by <>", value, "createBy");
return (Criteria) this;
}
public Criteria andCreateByGreaterThan(Long value) {
addCriterion("create_by >", value, "createBy");
return (Criteria) this;
}
public Criteria andCreateByGreaterThanOrEqualTo(Long value) {
addCriterion("create_by >=", value, "createBy");
return (Criteria) this;
}
public Criteria andCreateByLessThan(Long value) {
addCriterion("create_by <", value, "createBy");
return (Criteria) this;
}
public Criteria andCreateByLessThanOrEqualTo(Long value) {
addCriterion("create_by <=", value, "createBy");
return (Criteria) this;
}
public Criteria andCreateByIn(List<Long> values) {
addCriterion("create_by in", values, "createBy");
return (Criteria) this;
}
public Criteria andCreateByNotIn(List<Long> values) {
addCriterion("create_by not in", values, "createBy");
return (Criteria) this;
}
public Criteria andCreateByBetween(Long value1, Long value2) {
addCriterion("create_by between", value1, value2, "createBy");
return (Criteria) this;
}
public Criteria andCreateByNotBetween(Long value1, Long value2) {
addCriterion("create_by not between", value1, value2, "createBy");
return (Criteria) this;
}
public Criteria andCreateTimeIsNull() {
addCriterion("create_time is null");
return (Criteria) this;
}
public Criteria andCreateTimeIsNotNull() {
addCriterion("create_time is not null");
return (Criteria) this;
}
public Criteria andCreateTimeEqualTo(Date value) {
addCriterion("create_time =", value, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeNotEqualTo(Date value) {
addCriterion("create_time <>", value, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeGreaterThan(Date value) {
addCriterion("create_time >", value, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeGreaterThanOrEqualTo(Date value) {
addCriterion("create_time >=", value, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeLessThan(Date value) {
addCriterion("create_time <", value, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeLessThanOrEqualTo(Date value) {
addCriterion("create_time <=", value, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeIn(List<Date> values) {
addCriterion("create_time in", values, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeNotIn(List<Date> values) {
addCriterion("create_time not in", values, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeBetween(Date value1, Date value2) {
addCriterion("create_time between", value1, value2, "createTime");
return (Criteria) this;
}
public Criteria andCreateTimeNotBetween(Date value1, Date value2) {
addCriterion("create_time not between", value1, value2, "createTime");
return (Criteria) this;
}
}
public static class Criteria extends GeneratedCriteria {
protected Criteria() {
super();
}
}
public static class Criterion {
private String condition;
private Object value;
private Object secondValue;
private boolean noValue;
private boolean singleValue;
private boolean betweenValue;
private boolean listValue;
private String typeHandler;
public String getCondition() {
return condition;
}
public Object getValue() {
return value;
}
public Object getSecondValue() {
return secondValue;
}
public boolean isNoValue() {
return noValue;
}
public boolean isSingleValue() {
return singleValue;
}
public boolean isBetweenValue() {
return betweenValue;
}
public boolean isListValue() {
return listValue;
}
public String getTypeHandler() {
return typeHandler;
}
protected Criterion(String condition) {
super();
this.condition = condition;
this.typeHandler = null;
this.noValue = true;
}
protected Criterion(String condition, Object value, String typeHandler) {
super();
this.condition = condition;
this.value = value;
this.typeHandler = typeHandler;
if (value instanceof List<?>) {
this.listValue = true;
} else {
this.singleValue = true;
}
}
protected Criterion(String condition, Object value) {
this(condition, value, null);
}
protected Criterion(String condition, Object value, Object secondValue, String typeHandler) {
super();
this.condition = condition;
this.value = value;
this.secondValue = secondValue;
this.typeHandler = typeHandler;
this.betweenValue = true;
}
protected Criterion(String condition, Object value, Object secondValue) {
this(condition, value, secondValue, null);
}
}
}
public class SysUser {
private long id;
private String userName;
private String userPassword;
private String userEmail;
private String userInfo;
private byte[] headImg;
private Date createTime;
private List<SysRole> roleList;
/**
* mybatis 会先查询role对象，然后再role中继续寻找role.name
* 在这里纠正一个错误，是如果你多个表关联的话，例如 SysUser
* sql语句应该写成 r.id "role.id",
r.role_name "role.roleName",
r.enabled "role.enabled",
r.create_by "role.createBy" 等，要不然sys_role关联不出来的，
这样写需要一个实体类进行映射到另一个实体类上 ，增加了服务器压力，建议关联结果的嵌套查询
*/
@Test
public void testselectUserAndRoleId(){
SqlSession openSession = sql.openSession();
SysUserMapper mapper = openSession.getMapper(SysUserMapper.class);
SysUser selectUserAndRoleId = mapper.selectUserAndRoleId(1);
System.out.println(selectUserAndRoleId);
}
/**
* 使用resultmap 进行配置一对一映射
*
*/
@Test
public void testselectUserAndRoleId2(){
SqlSession openSession = sql.openSession();
SysUserMapper mapper = openSession.getMapper(SysUserMapper.class);
SysUser selectUserAndRoleId = mapper.selectUserAndRoleId2(1);
System.out.println(selectUserAndRoleId);
}
/**
* 使用一对多映射 collection
* Result Maps collection does not contain value for com.mybatis.demo.mapperSysRoleMapper.BaseResultMap
*
*/
@Test
public void testselectUserAndRoleId3(){
SqlSession openSession = sql.openSession();
SysUserMapper mapper = openSession.getMapper(SysUserMapper.class);
List<SysUser> selectUserAndRoleId3 = mapper.selectUserAndRoleId3(1);
System.out.println(selectUserAndRoleId3);
}
}
主要是一对多的时候，应该是oftype，要不然不会参数类型不匹配异常