mybatis之一对一关联

 

 

MapperAsso.xml

 1 <?xml version="1.0" encoding="UTF-8" ?>
 2 <!DOCTYPE mapper
 3         PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
 4         "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 5 
 6 <mapper namespace="bean.User">
 7     <!--一对一关联-->
 8     <select id="selectOneAssoObj" parameterType="int" resultMap="OneAssoObjRM">
 9         select * from user where id = #{id}
10     </select>
11     <resultMap type="association.AssoObj" id="OneAssoObjRM">
12         <result property="id" column="id"/>
13         <result property="name" column="name"/>
14         <result property="age" column="age"/>
15         <association  property="salary" column="name" select="selectOneSalary"/>
16         <!--一对多关联配置备注-->
17         <!--<collection property="salarys" ofType="bean.Salary" column="name" select="selectFewSalarys">-->
18     </resultMap>
19 
20     <select id="selectOneSalary" parameterType="String" resultType="bean.Salary">
21         select * from salary where name = #{name}
22     </select>
23 
24     <!--id:名称; parameterType传入参数类型; resultType:返回数据类型-->
25     <select id="selectOneUser" parameterType="int" resultType="bean.User">
26         select * from user where id = #{id}
27     </select>
28 
29     <!--批量查询-->
30     <select id="selectAllUser" resultMap="userList">
31         select * from user
32     </select>
33     <resultMap type="first.UserBean" id="userList">
34         <result property="id" column="id"/>
35         <result property="name" column="name"/>
36         <result property="age" column="age"/>
37     </resultMap>
38 
39 
40 </mapper>

 

AssoObj.java

 1 package association;
 2 
 3 import bean.Salary;
 4 
 5 /**
 6  * 数据封装类
 7  * user class with Salary object
 8  * 一对一关联Javabean
 9  */
10 public class AssoObj {
11     private int id;
12     private String name;
13     private String age;
14     private Salary salary;
15 
16     public AssoObj() {
17 
18     }
19 
20     public AssoObj(String name, String age) {
21         this.name = name;
22         this.age = age;
23     }
24 
25     public AssoObj(int id, String name, String age, Salary salary) {
26         this.id = id;
27         this.name = name;
28         this.age = age;
29         this.salary = salary;
30     }
31 
32     public String getName() {
33         return name;
34     }
35 
36     public void setName(String name) {
37         this.name = name;
38     }
39 
40     public String getAge() {
41         return age;
42     }
43 
44     public void setAge(String age) {
45         this.age = age;
46     }
47 
48     public int getId() {
49         return id;
50     }
51 
52     public void setId(int id) {
53         this.id = id;
54     }
55 
56     public Salary getSalary() {
57         return salary;
58     }
59 
60     public void setSalary(Salary salary) {
61         this.salary = salary;
62     }
63 
64     @Override
65     public String toString() {
66         return "AssoObj{id:" + id + "; 姓名:" + name +
67                 "; 年龄:" + age + "; Salary对象:" + salary + "}";
68     }
69 }

 

TestAsso.java

 1 package association;
 2 
 3 import bean.Salary;
 4 import bean.User;
 5 import bean.UserSalary;
 6 import first.UserBean;
 7 import org.apache.ibatis.io.Resources;
 8 import org.apache.ibatis.session.SqlSession;
 9 import org.apache.ibatis.session.SqlSessionFactory;
10 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
11 import org.junit.After;
12 import org.junit.Before;
13 import org.junit.Ignore;
14 import org.junit.Test;
15 import zhujie.UserMapperInterface;
16 
17 import java.io.IOException;
18 import java.io.InputStream;
19 import java.util.List;
20 
21 /*
22 * 一对一关联举例
23 *
24 * */
25 public class TestAsso {
26     String resource = "mybatis-config-assosciation.xml";
27     SqlSessionFactory sqlSessionFactory = null;
28     SqlSession session = null;
29 
30     @Before
31     public void before() {
32 //        System.out.println("Before");
33         try {
34             InputStream inputStream = Resources.getResourceAsStream(resource);
35 //            创建工厂
36             sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
37 //            创建session对象
38             session = sqlSessionFactory.openSession();
39 
40         } catch (IOException e) {
41             e.printStackTrace();
42         }
43     }
44 
45     @After
46     public void close() {
47         session.close();
48 //        System.out.println("After");
49     }
50 
51     //    一对一关联测试用例
52     @Test
53     public void testSelectOneAssoObj() {
54         AssoObj assoObj = session.selectOne("bean.User.selectOneAssoObj", 1);
55         System.out.println("查询单个AssoObj:" + assoObj);
56     }
57 
58     @Test
59     public void testSelectOneUser() {
60         User user = session.selectOne("bean.User.selectOneUser", 1);
61         System.out.println("查询单个User:" + user);
62     }
63 
64     @Test
65     public void testSelectAllUser() {
66         List<User> listUser = session.selectList("bean.User.selectAllUser");
67         System.out.println("记录个数:" + listUser.size());
68         System.out.println(listUser);
69     }
70 
71     @Test
72     public void testSelectOneSalary() {
73         Salary salary = session.selectOne("bean.User.selectOneSalary", "Tom");
74         System.out.println("查询单个Salary:" + salary);
75     }
76 
77 
78 }

 

mybatis-config-assosciation.xml

 1 <?xml version="1.0" encoding="UTF-8" ?>
 2 <!DOCTYPE configuration
 3         PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
 4         "http://mybatis.org/dtd/mybatis-3-config.dtd">
 5 <configuration>
 6     <!--从外部配置文件导入jdbc信息-->
 7     <properties resource="jdbc.properties"></properties>
 8 
 9     <environments default="development">
10         <environment id="development">
11             <transactionManager type="JDBC"/>
12             <dataSource type="POOLED">
13                 <property name="driver" value="${driver}"/>
14                 <property name="url" value="${url}"/>
15                 <property name="username" value="${username}"/>
16                 <property name="password" value="${password}"/>
17             </dataSource>
18         </environment>
19     </environments>
20 
21     <!--指定映射资源文件-->
22     <mappers>
23         <mapper resource="association/MapperAsso.xml"/>
24 
25     </mappers>
26 </configuration>

 

posted @ 2018-01-15 15:29  星瑞  阅读(369)  评论(0编辑  收藏  举报