1、有用户和代表团两个实体一个用户对应一个代表团

       用户实体

package com.qf.meeting.pojo;
import java.io.Serializable;
import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;

public class User implements Serializable{
	private final static Logger LOG = LogManager.getLogger(User.class);
	private Integer userId;
	private String userLoginName;
	private String userTel;
	private String userPwd;
	private String photo;
	private String userName;
	private Delegation delegation;
	public User() {
		super();
	}
	public User(Integer userId, String userLoginName, String userTel, String userPwd, String photo, String userName,
			Delegation delegation) {
		super();
		this.userId = userId;
		this.userLoginName = userLoginName;
		this.userTel = userTel;
		this.userPwd = userPwd;
		this.photo = photo;
		this.userName = userName;
		this.delegation = delegation;
	}
	public Integer getUserId() {
		return userId;
	}
	public void setUserId(Integer userId) {
		this.userId = userId;
	}
	public String getUserLoginName() {
		return userLoginName;
	}
	public void setUserLoginName(String userLoginName) {
		this.userLoginName = userLoginName;
	}
	public String getUserTel() {
		return userTel;
	}
	public void setUserTel(String userTel) {
		this.userTel = userTel;
	}
	public String getUserPwd() {
		return userPwd;
	}
	public void setUserPwd(String userPwd) {
		this.userPwd = userPwd;
	}
	public String getPhoto() {
		return photo;
	}
	public void setPhoto(String photo) {
		this.photo = photo;
	}
	public String getUserName() {
		return userName;
	}
	public void setUserName(String userName) {
		this.userName = userName;
	}
	public Delegation getDelegation() {
		return delegation;
	}
	public void setDelegation(Delegation delegation) {
		this.delegation = delegation;
	}
	@Override
	public String toString() {
		return "User [userId=" + userId + ", userLoginName=" + userLoginName + ", userTel=" + userTel + ", userPwd="
				+ userPwd + ", photo=" + photo + ", userName=" + userName + ", delegation=" + delegation + "]";
	}
	
	
}

    代表团实体

package com.qf.meeting.pojo;
import java.io.Serializable;

import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;
public class Delegation implements Serializable{
	private final static Logger LOG = LogManager.getLogger(Delegation.class);

	private Integer delegationId;
	
	private String delegationName;

	public Delegation() {
		super();
	}

	public Delegation(Integer delegationId, String delegationName) {
		super();
		this.delegationId = delegationId;
		this.delegationName = delegationName;
	}

	public Integer getDelegationId() {
		return delegationId;
	}

	public void setDelegationId(Integer delegationId) {
		this.delegationId = delegationId;
	}

	public String getDelegationName() {
		return delegationName;
	}

	public void setDelegationName(String delegationName) {
		this.delegationName = delegationName;
	}

	@Override
	public String toString() {
		return "Delegation [delegationId=" + delegationId + ", delegationName=" + delegationName + "]";
	}
	
}

2、查询所有的用户

<?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.qf.meeting.mapper.UserMapper">

 <resultMap type="com.qf.meeting.pojo.User" id="UserResultMap">
 	<id property="userId" column="userId"/>
 	<result property="userLoginName" column="userLoginName"/>
 	<result property="userTel" column="userTel"/>
 	<result property="userPwd" column="userPwd"/>
 	<result property="photo" column="photo"/>
 	<result property="userName" column="userName"/>
 	<association property="delegation" column="delegationId" javaType="com.qf.meeting.pojo.Delegation" autoMapping="true">
 	<id property="delegationId" column="delegationId"/>
 	</association>
 </resultMap>
 
 <select id="findAllUser" resultMap="UserResultMap">
 	select * from t_user u ,t_delegation d where u.delegationId = d.delegationId;
 </select>
 </mapper>

  查询结果

[{"userId":1,"userLoginName":"**","userTel":"*********","userPwd":"123456","photo":"***.jpg","userName":"****","delegation":{"delegationId":1,"delegationName":"电力局代表团"}},
{"userId":2,"userLoginName":"**","userTel":"*********","userPwd":"123456","photo":"***.jpg","userName":"***","delegation":{"delegationId":1,"delegationName":"电力局代表团"}}]