The error processing mechanism and abnormal processing principle in the MapStruct Core framework

The error handling mechanism and abnormal processing principle in the MapStruct Core framework Overview: Error processing is a vital part of the software development process.In the MapStruct Core framework, the error processing mechanism and abnormal processing principles are considered an important part of ensuring the quality and reliability of the code.This article will introduce the error processing mechanism and abnormal processing principles in the MapStruct Core framework, and explain the related programming code and configuration in order to better understand. Error treatment mechanism: 1. Check and verification: The MapStruct Core framework is effective through verification and verification to ensure that the data conversion between the source and the target object is effective.By using annotations in mapping interfaces or classes, such as@notnull,@notempty,@siZe, etc., you can check the data verification and verification.If the data in the source object is invalid, the Mapstruct Core framework will throw an exception. 2. Map failure processing: In some cases, data conversion may fail, such as the field name between the source and the target object does not match.To deal with this failure of this mapping, the MapStruct Core framework provides an abnormal processing mechanism.Users can customize the failed to process mapping by implementing error mapping interfaces provided by MapStruct, such as MAPPINENGEXCEPTION, MAPPINGNOTFOUNDEXCEPION, etc.These abnormalities can be captured and processed by custom abnormal processors. 3. Map configuration: MapStruct Core framework supports a definition error processing mechanism through configuration.In the mapping interface, you can use the Exceptionsubstitute property annotation of @Mapper to specify the implementation class of the error processor.The implementation class needs to implement anomalial mapping interface provided by MapStruct and cover the method that needs to be customized.By using custom abnormal processors, more flexible and accurate errors can be achieved. Principles of abnormal treatment: 1. Easy debugging: When designing and implementing abnormal treatment, the principle of easy debugging should be taken into account.Abnormal information should contain sufficient context information to help developers quickly locate problems.In addition, abnormal stack tracking should also be clear to track the position of abnormal occurrence. 2. Easy maintenance: exception treatment should have good maintenance.Avoid writing business logic directly in abnormal processing codes, and separate business logic and abnormal processing logic should be separated to improve the readability and maintenance of the code.Abnormal processing should be simple and clear, avoid redundant code, and follow the design mode and best practice. 3. Appropriate response: exception treatment should appropriately reflect the actual situation and use cases.Different types of abnormal types should have different ways to deal with, for example, you can decide whether to take data back, review, record logs, etc. according to the abnormal type.Appropriate reactions can improve the stability of the system and user experience. Programming code and related configuration: The following is a mapping interface and configuration example of a simple MapStruct Core framework: @Mapper (Exceptionsubstitute = CustomExceptionMapper.class) // Configure an exception processor public interface UserMapper { UserMapper INSTANCE = Mappers.getMapper(UserMapper.class); @Mapping(source = "name", target = "fullName") @Mapping(source = "email", target = "emailAddress") UserDTO userToUserDTO(User user); @Mapping(source = "fullName", target = "name") @Mapping(source = "emailAddress", target = "email") User userDTOToUser(UserDTO userDTO); } public class CustomExceptionMapper implements ExceptionMapper<CustomMappingException> { // Customized abnormal processing logic @Override public void handleException(CustomMappingException exception) { // Treatment the mapping failure situation // ... } } In the above example, the UserMapper interface uses @Mapper annotations to specify the custom abnormal processor CustomExceptionMapper.In addition, the interface also defines two mapping methods to convert the User object to UserDTO object and convert the UserDTO object back to the User object.The CustomExceptionMapper implements the ExceptionMapper interface provided by MapStruct and covers the handleexception method for custom logic. The above is a brief introduction to the error processing mechanism and abnormal processing principles in the MapStruct Core framework.By properly handling errors and abnormalities, the reliability and stability of the code can be improved and the user experience can be improved.