* 使用mybatis举例，使用DAO接口方式实现
* 不需要针对接口去编写具体的实现类代码，编写映射XML文件，直接拿来使用即可。
* 1、导入jar包：mybatis和mysql-connector
* 2、mybatis配置文件：mybatis-config.xml，加载映射XML文件
* 3、编写JavaBean类，如UserBean
* 4、编写DAO接口和映射XML文件（namespace=DAO接口文件路径、id=接口方法名）
mybatis-config-dao.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="dao/DaoMapper.xml"/>
24
25 </mappers>
26 </configuration>
DaoMapper.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="dao.UserDao">
7 <!--id：名称； parameterType传入参数类型； resultType：返回数据类型-->
8 <select id="selectOneUser" parameterType="int" resultType="bean.User">
9 select * from user where id = #{id}
10 </select>
11
12 <!--批量查询-->
13 <select id="selectAllUser" resultMap="userList">
14 select * from user
15 </select>
16 <resultMap type="bean.User" id="userList">
17 <result property="id" column="id"/>
18 <result property="name" column="name"/>
19 <result property="age" column="age"/>
20 </resultMap>
21
22 <insert id="insertUser" useGeneratedKeys="true" keyProperty="id">
23 insert into user (id, name, age) values (#{id} ,#{name}, #{age})
24 </insert>
25
26 <update id="updateUser">
27 update user set name=#{name},age=#{age} where id=#{id}
28 </update>
29
30 <delete id="deleteUser">
31 delete from user where id=#{id}
32 </delete>
33
34 <!-- 传入多个参数时，自动转换为map形式 -->
35 <insert id="insertByColumns" useGeneratedKeys="true" keyProperty="id">
36 insert into user (id, name, age) values (NULL ,#{param1}, #{param2})
37 </insert>
38 <insert id="insertByZhuJie" useGeneratedKeys="true" keyProperty="id">
39 insert into user (id, name, age) values (NULL ,#{name}, #{age})
40 </insert>
41 <insert id="insertByMap" useGeneratedKeys="true" keyProperty="id">
42 insert into user (id, name, age) values (NULL ,#{name}, #{age})
43 </insert>
44
45 </mapper>
UserDao.java
1 package dao;
2
3 import bean.User;
4 import org.apache.ibatis.annotations.Param;
5
6
7 import java.util.List;
8 import java.util.Map;
9
10 /*
11 * 使用mybatis举例，使用DAO接口方式实现
12 * 不需要针对UserMapperI接口去编写具体的实现类代码，这个具体的实现类由MyBatis帮我们动态构建出来，我们只需要直接拿来使用即可。
13 * */
14 public interface UserDao {
15
16 // 根据id查询单一数据
17 public User selectOneUser(int id);
18
19 // 查询所有用户
20 public List<User> selectAllUser();
21
22 // 插入数据
23 public int insertUser(User user);
24
25 // 修改用户
26 public int updateUser(User user);
27
28 // 删除用户
29 public int deleteUser(User user);
30
31 // 插入数据；多参数三种方式：默认Map、使用Map传参和使用注解别名
32 public int insertByColumns(String name, int age);
33 public int insertByZhuJie(@Param("name") String name, @Param("age") int age);
34 public int insertByMap(Map map);
35
36 }
TestDao.java
1 package dao;
2
3 import bean.User;
4 import org.apache.ibatis.io.Resources;
5 import org.apache.ibatis.session.SqlSession;
6 import org.apache.ibatis.session.SqlSessionFactory;
7 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
8 import org.junit.After;
9 import org.junit.Before;
10 import org.junit.Ignore;
11 import org.junit.Test;
12
13 import java.io.IOException;
14 import java.io.InputStream;
15 import java.util.HashMap;
16 import java.util.List;
17 import java.util.Map;
18
19 /*
20 * 使用mybatis举例，使用DAO接口方式实现
21 * 不需要针对接口去编写具体的实现类代码，编写映射XML文件，直接拿来使用即可。
22 * 1、导入jar包：mybatis和mysql-connector
23 * 2、mybatis配置文件：mybatis-config.xml，加载映射XML文件
24 * 3、编写JavaBean类，如UserBean
25 * 4、编写DAO接口和映射XML文件（namespace=DAO接口文件路径、id=接口方法名）
26 * */
27 public class TestDao {
28 String resource = "mybatis-config-dao.xml";
29 SqlSessionFactory sqlSessionFactory = null;
30 SqlSession session = null;
31
32 @Before
33 public void before() {
34 // System.out.println("Before");
35 try {
36 InputStream inputStream = Resources.getResourceAsStream(resource);
37 // 创建工厂
38 sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
39 // 创建session对象
40 session = sqlSessionFactory.openSession();
41
42 } catch (IOException e) {
43 e.printStackTrace();
44 }
45 }
46
47 @After
48 public void close() {
49 session.close();
50 // System.out.println("After");
51 }
52
53 @Test
54 public void testSelectOneUser() {
55 // 接口自动实例化
56 UserDao userDao = session.getMapper(UserDao.class);
57 // 执行sql
58 User user = userDao.selectOneUser(1);
59 System.out.println(user);
60 }
61
62 // 批量查询
63 @Test
64 public void testSelectAllUser() {
65 // 接口自动实例化
66 UserDao userDao = session.getMapper(UserDao.class);
67 // 执行sql
68 List<User> listUser = userDao.selectAllUser();
69 System.out.println("记录个数：" + listUser.size());
70 System.out.println(listUser);
71 }
72
73 // 插入数据
74 @Ignore
75 @Test
76 public void testInsertUser() {
77 UserDao userDao = session.getMapper(UserDao.class);
78 User user = new User("AA", "29");
79 int n = userDao.insertUser(user);
80 session.commit();
81 System.out.println("插入数据：" + user);
82 System.out.println(n);
83 }
84
85 // 修改数据
86 @Ignore
87 @Test
88 public void testUpdateUser() {
89 UserDao userDao = session.getMapper(UserDao.class);
90 User user = new User(2, "Tom5", "29");
91 int n = userDao.updateUser(user);
92 session.commit();
93 System.out.println("修改数据：" + user);
94 System.out.println(n);
95 }
96
97 // 修改数据
98 @Ignore
99 @Test
100 public void testDeleteUser() {
101 UserDao userDao = session.getMapper(UserDao.class);
102 User user = new User(13, "XX", "XX");
103 int n = userDao.deleteUser(user);
104 session.commit();
105 System.out.println("删除数据：" + user);
106 System.out.println(n);
107 }
108
109 // 多参数插入数据的三种方式
110 @Ignore
111 @Test
112 public void testInsertByColumns() {
113 UserDao userDao = session.getMapper(UserDao.class);
114 String name = "insertByColumns";
115 int age = 33;
116 // int n = userDao.insertByColumns(name, age);
117 // int n = userDao.insertByZhuJie(name, age);
118
119 Map map = new HashMap();
120 map.put("name", name);
121 map.put("age", age);
122 int n = userDao.insertByMap(map);
123
124 session.commit();
125 System.out.println("插入数据name：" + name);
126 System.out.println(n);
127 }
128
129
130 }
User.java
1 package bean;
2
3 /**
4 * 数据封装类
5 * JavaBean
6 */
7 public class User {
8 private int id;
9 private String name;
10 private String age;
11
12 public User() {
13
14 }
15
16 public User(String name, String age) {
17 this.name = name;
18 this.age = age;
19 }
20 public User(int id, String name, String age) {
21 this.id = id;
22 this.name = name;
23 this.age = age;
24 }
25
26 public String getName() {
27 return name;
28 }
29
30 public void setName(String name) {
31 this.name = name;
32 }
33
34 public String getAge() {
35 return age;
36 }
37
38 public void setAge(String age) {
39 this.age = age;
40 }
41
42 public int getId() {
43 return id;
44 }
45
46 public void setId(int id) {
47 this.id = id;
48 }
49
50 @Override
51 public String toString() {
52 return "User{id：" + id + "; 姓名：" + name + "; 年龄：" + age + "}";
53 }
54 }
