Data Access 之 MyBatis（八）- MyBatis 通用 Mapper（Part A）（下）

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:application.xml")
public class PorscheMapperTest {
    @Resource
    private PorscheMapper porscheMapper;
    @Test
    public void getPorscheById(){
        Porsche panamera = porscheMapper.getPorscheById(1);
        System.out.println("查询到的内容为：" + panamera);
    }
}
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<dependency>
    <groupId>tk.mybatis</groupId>
    <artifactId>mapper</artifactId>
    <version>4.1.5</version>
</dependency>
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<bean id="sqlSessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
    <!--其他内容不变-->
    <!--Mapper XML的配置注销，使用通用Mapper就不再需要Mapper XML了-->
    <!--<property name="mapperLocations" value="classpath:mappers/*.xml"></property>-->
</bean>
<!--Dao层接口加入到Spring容器， 使用tk包下面的MapperScannerConfigurer，原来是org开头-->
<bean id="mapperScannerConfigurer" class="tk.mybatis.spring.mapper.MapperScannerConfigurer">
    <!--其他内容不变-->
    <property name="basePackage" value="com.citi.mapper"></property>
</bean>
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public interface TeacherMapper extends Mapper<Teacher> {
}
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public interface PorscheMapper extends Mapper<Porsche> {
}
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public interface PorscheService {
    Porsche getOne(Porsche record);
}
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@Service
public class PorscheServiceImpl implements PorscheService {
    @Autowired
    private PorscheMapper porscheMapper;
    @Override
    public Porsche getOne(Porsche record) {
        return porscheMapper.selectOne(record);
    }
}
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@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:application.xml")
public class PorscheServiceTest {
    @Autowired
    private PorscheService porscheService;
    @Test
    public void getOne() {
        // 构造查询条件
        Porsche record = new Porsche();
        record.setPorName("Cayenne");
        record.setPorPrice(910000d);
        // 执行查询
        Porsche porsche = porscheService.getOne(record);
        System.out.println("查询到的内容为：" + porsche);
    }
}
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public interface TeacherService {
    Teacher getOne(Teacher record);
}
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@Service
public class TeacherServiceImpl implements TeacherService {
    @Autowired
    private TeacherMapper teacherMapper;
    @Override
    public Teacher getOne(Teacher record) {
        return teacherMapper.selectOne(record);
    }
}
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@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:application.xml")
public class TeacherServiceTest {
    @Autowired
    private TeacherService teacherService;
    @Test
    public void getOne() {
        // 构造查询条件
        Teacher record = new Teacher();
        record.setGrade("三年二班");
        record.setName("stark");
        Teacher teacher = teacherService.getOne(record);
        System.out.println(teacher);
    }
}
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@Data
@Table(name = "t_teacher")
public class Teacher {
    private Integer id;
    @Column(name = "teacher_name")
    private String name;
    // 执教的年级
    @Column(name = "class_name")
    private String grade;
    private String address;
    private Date birthDate;
}
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// 根据实体中的属性值进行查询，返回List列表，查询条件使用等号
List<T> select(T record);
// 查询全部结果，返回List列表
List<T> selectAll();
// 根据实体中的属性查询总数，返回int类型，查询条件使用等号
int selectCount(T record);
// 根据主键字段进行查询，方法参数必须包含完整的主键属性，返回一个实体类，查询条件使用等号
T selectByPrimaryKey(Object key);
// 根据主键字段查询总数，方法参数必须包含完整的主键属性，返回True或者False查询条件使用等号
boolean existsWithPrimaryKey(Object key);
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Porsche getPorscheById(Integer id);
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@Override
public Porsche getPorscheById(Integer id) {
    return porscheMapper.selectByPrimaryKey(id);
}
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@Test
public void getPorscheById(){
    Porsche porsche = porscheService.getPorscheById(2);
    System.out.println("查询到的内容为：" + porsche);
}
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Boolean isExists(Integer id);
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@Override
public Boolean isExists(Integer id) {
    return porscheMapper.existsWithPrimaryKey(id);
}
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@Test
public void isExists(){
    Integer id = 30;
    Boolean exists = porscheService.isExists(id);
    System.out.println("是否存在主键为" + id + "的记录：" + exists);
}
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