使用mybatis实现一个动物园管理的增删改查

假设我们有一个动物园管理系统，需要对动物信息进行增删改查操作，我们可以使用MyBatis来实现。下面是一个使用XML方式配置MyBatis的示例：

1. 创建动物类Animal.java

public class Animal {
    private int id;
    private String name;
    private String species;
    private int age;
    // 省略getter和setter方法
}

2. 创建动物表的数据库脚本

CREATE TABLE animal (
  id INT PRIMARY KEY AUTO_INCREMENT,
  name VARCHAR(50) NOT NULL,
  species VARCHAR(50) NOT NULL,
  age INT NOT NULL
);

3. 创建MyBatis的配置文件mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <typeAliases>
        <typeAlias type="com.example.Animal" alias="Animal"/>
    </typeAliases>

    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/test"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <mapper resource="com/example/mapper/AnimalMapper.xml"/>
    </mappers>
</configuration>

4. 创建AnimalMapper.xml，定义SQL语句和参数映射

<?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.example.mapper.AnimalMapper">
    <resultMap id="AnimalResultMap" type="Animal">
        <id property="id" column="id"/>
        <result property="name" column="name"/>
        <result property="species" column="species"/>
        <result property="age" column="age"/>
    </resultMap>

    <select id="getAnimalById" resultMap="AnimalResultMap" parameterType="int">
        SELECT * FROM animal WHERE id = #{id}
    </select>

    <select id="getAllAnimals" resultMap="AnimalResultMap">
        SELECT * FROM animal
    </select>

    <insert id="addAnimal" parameterType="Animal">
        INSERT INTO animal (name, species, age)
        VALUES (#{name}, #{species}, #{age})
    </insert>

    <update id="updateAnimal" parameterType="Animal">
        UPDATE animal SET name = #{name}, species = #{species}, age = #{age} WHERE id = #{id}
    </update>

    <delete id="deleteAnimalById" parameterType="int">
        DELETE FROM animal WHERE id = #{id}
    </delete>
</mapper>

5. 创建AnimalMapper.java，定义接口方法

public interface AnimalMapper {
    Animal getAnimalById(int id);

    List<Animal> getAllAnimals();

    void addAnimal(Animal animal);

    void updateAnimal(Animal animal);

    void deleteAnimalById(int id);
}

6. 编写测试类进行测试

public class AnimalTest {
    private SqlSession sqlSession;
    private AnimalMapper animalMapper;

    @Before
    public void setUp() throws Exception {
        Reader reader = Resources.getResourceAsReader("mybatis-config.xml");
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
        sqlSession = sqlSessionFactory.openSession();
        animalMapper = sqlSession.getMapper(AnimalMapper.class);
    }

    @Test
    public void testGetAnimalById() {
        Animal animal = animalMapper.getAnimalById(1);
        System.out.println(animal.getName());
    }

    @Test
    public void testGetAllAnimals() {
        List<Animal> animals = animalMapper.getAllAnimals();
        for (Animal animal : animals) {
            System.out.println(animal.getName());
        }
    }

    @Test
    public void testAddAnimal() {
        Animal animal = new Animal();
        animal.setName("Tom");
        animal.setSpecies("Cat");
        animal.setAge(2);
        animalMapper.addAnimal(animal);
        sqlSession.commit();
    }

    @Test
    public void testUpdateAnimal() {
        Animal animal = animalMapper.getAnimalById(1);
        animal.setName("Jerry");
        animal.setSpecies("Mouse");
        animalMapper.updateAnimal(animal);
        sqlSession.commit();
    }

    @Test
    public void testDeleteAnimalById() {
        animalMapper.deleteAnimalById(1);
        sqlSession.commit();
    }

    @After
    public void tearDown() throws Exception {
        sqlSession.close();
    }
}

以上就是使用MyBatis进行动物园管理系统的增删改查操作的示例。