mapstruct进阶用法《一》

 一.mapstruct除了能自动映射字段属性，也可以定义javaBean见得规则进行映射

/**
 * 使用自定义的映射器BooleanStr
 */
@Mapper(uses ={BooleanStr.class})
public interface CustomerInterface {
    CustomerInterface INSTANCE= Mappers.getMapper(CustomerInterface.class);

    @Mappings({
            @Mapping(source = "name", target = "customerName"),
            @Mapping(source = "isDisable", target = "disable")
    })
    CustomerDto toCustomerDto(Customer customer);
}

二.自定义映射规则BooleanStr 后，就可以把Customer的Boolean属性转换成目标bean的String类型

/**
 * 自定义转换规则的类
 */
public class BooleanStr {

    public String toStr(Boolean isDisable) {
        if (isDisable) {
            return "Y";
        } else {
            return "N";
        }
    }
    public Boolean toBoolean(String str) {
        if (str.equals("Y")) {
            return true;
        } else {
            return false;
        }
    }
}

@Generated(
    value = "org.mapstruct.ap.MappingProcessor",
    date = "2022-01-25T16:15:32+0800",
    comments = "version: 1.3.1.Final, compiler: javac, environment: Java 1.8.0_91 (Oracle Corporation)"
)
public class CustomerInterfaceImpl implements CustomerInterface {

    private final BooleanStr booleanStr = new BooleanStr();

    @Override
    public CustomerDto toCustomerDto(Customer customer) {
        if ( customer == null ) {
            return null;
        }

        CustomerDto customerDto = new CustomerDto();

        customerDto.setDisable( booleanStr.toStr( customer.getIsDisable() ) );
        customerDto.setCustomerName( customer.getName() );
        customerDto.setId( customer.getId() );

        return customerDto;
    }
}

2.除了上面自定义规则外还可以把目标bean同过注入容器的方式来处理比如下面所示：

/**
 * 这里主要是这个componentModel 属性，它的值就是当前要使用的依赖注入的环境
 * 必须要引入spring的jar包
 */
@Mapper(componentModel = "spring")
public interface RefundInterface {
    RefundInterface INSTANCE= Mappers.getMapper(RefundInterface.class);
    @Mappings({
            @Mapping(source = "shardKey",target = "key")
    })
    RefundVo refundTo(Refund refund);

}

@Generated(
    value = "org.mapstruct.ap.MappingProcessor",
    date = "2022-01-25T16:15:32+0800",
    comments = "version: 1.3.1.Final, compiler: javac, environment: Java 1.8.0_91 (Oracle Corporation)"
)
@Component
public class RefundInterfaceImpl implements RefundInterface {

    @Override
    public RefundVo refundTo(Refund refund) {
        if ( refund == null ) {
            return null;
        }

        RefundVo refundVo = new RefundVo();

        refundVo.setKey( refund.getShardKey() );

        return refundVo;
    }
}

上述可以以组件的方式注入容器，在需要的地方进行AtuoWrite使用

三.除了一，二分别制定spring容器和自定义规则
另外，还可以把自定义规则以springbean的形式注入到映射目标的实现中去，实现“自动化”无感知的的便捷。

这里还是以上面的为例

/**
 * 使用自定义的映射器BooleanStr
 */
@Mapper(uses ={BooleanStr.class},componentModel ="spring")
public interface CustomerInterface {
    CustomerInterface INSTANCE= Mappers.getMapper(CustomerInterface.class);

    @Mappings({
            @Mapping(source = "name", target = "customerName"),
            @Mapping(source = "isDisable", target = "disable")
    })
    CustomerDto toCustomerDto(Customer customer);
}

@Generated(
    value = "org.mapstruct.ap.MappingProcessor",
    date = "2022-01-25T17:08:28+0800",
    comments = "version: 1.3.1.Final, compiler: javac, environment: Java 1.8.0_91 (Oracle Corporation)"
)
@Component
public class CustomerInterfaceImpl implements CustomerInterface {

    @Autowired
    private BooleanStr booleanStr;

    @Override
    public CustomerDto toCustomerDto(Customer customer) {
        if ( customer == null ) {
            return null;
        }

        CustomerDto customerDto = new CustomerDto();

        customerDto.setDisable( booleanStr.toStr( customer.getIsDisable() ) );
        customerDto.setCustomerName( customer.getName() );
        customerDto.setId( customer.getId() );

        return customerDto;
    }
}

/**
 * 自定义转换规则的类  
* 也可以根据业务自己实现去注入，原理一样的这里不再赘述
 */
@Component
public class BooleanStr {

    public String toStr(Boolean isDisable) {
        if (isDisable) {
            return "Y";
        } else {
            return "N";
        }
    }
    public Boolean toBoolean(String str) {
        if (str.equals("Y")) {
            return true;
        } else {
            return false;
        }
    }
}

总结：