How to resolve MyBatis type handler not working issue

If MyBatis TypeHandler is not working, you can try the following solutions.

1. Ensure that the TypeHandler is configured correctly: check if the package path and class name of the TypeHandler are correctly configured in the MyBatis configuration file.
2. Check TypeHandler registration: Ensure that the TypeHandler has been properly registered in the MyBatis configuration. The TypeHandler can be registered in the MyBatis configuration file using the element or in Java code using the typeHandlerRegistry.register() method.
3. Check the generic type of the TypeHandler to ensure it matches the database field type. For example, if you need to handle a string field, the generic type of the TypeHandler should be String.
4. Verify the mapping of database fields to Java types: Ensure that the types of database fields match the object properties in Java. For example, if a database field is of type VARCHAR, the property of the Java object should be of type String.
5. Check if custom type handlers are being used: if custom type handlers are in use, make sure the handlers’ code is accurate and capable of correctly processing data.
6. Check if aliases are used: if aliases are used for TypeHandlers in the MyBatis configuration file, make sure that the aliases match the actual TypeHandler class names.
7. Check for any errors in field or attribute names: Ensure that the database fields match the properties of the Java objects, or use the @Result annotation to specify the mapping relationship between database fields and Java object properties.

If the above solutions still cannot solve the problem, you can try enabling MyBatis logging to check if there are any error messages related to TypeHandlers in the logs, in order to better locate and resolve the issue.