Mapper系列三：自定义Mapper接口

冷不防 2022-04-25 01:24 308阅读 0赞

自定义 Mapper接口。根据开发的实际需要对 Mapper接口进行定制  
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1、创建自定义 Mapper接口。注意：自定义的Mapper接口不能和EmployeeMapper放在同一个包下。

/**
     * 自定义接口根据需要选择要继承的接口
     */
    public interface MyMapper<T> 
    		extends SelectAllMapper<T>,SelectByExampleMapper<T> {
    
    }

2、EmployeeMapper 继承自定义的Mapper接口

public interface EmployeeMapper extends MyMapper<Employee> {
    
    }

3、在spring配置文件中配置自定义Mapper接口

<bean class="tk.mybatis.spring.mapper.MapperScannerConfigurer">
    	<property name="basePackage" value="com.atguigu.mapper.mappers"/>
    		
    	<property name="properties">
    		<value>
    			mappers=com.atguigu.mapper.mine_mappers.MyMapper
    		</value>
    	</property>
    </bean>

测试：

public class MyMapperTest {
    	
    	public static void main(String[] args) {
    		ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring-context.xml");
    		EmployeeService employeeService = context.getBean(EmployeeService.class);
    		
    		List<Employee> empList = employeeService.getAll();
    		for (Employee employee : empList) {
    			System.out.println(employee);
    		}
    		
    		context.close();
    	}
    
    }

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