


How to get Java entity class attribute names elegantly to avoid hard-coded in MyBatis queries?
Apr 19, 2025 pm 08:27 PM When using MyBatis-Plus or tk.mybatis for database queries, using string splicing attribute names (for example, criteria.andEqualTo("isdeleted", deleteFlagenum.undelete.getCode())
) directly reduces code readability and maintainability. This article discusses how to elegantly obtain Java entity class attribute names to avoid this hard coding.
The core of the problem: When building database query conditions, how to avoid directly using strings to represent entity class attribute names, such as dog.isdeleted
instead of "isdeleted"
to improve code quality. Sample code:
Example example = new Example(Dog.class); Example.Criteria criteria = example.createCriteria(); criteria.andEqualTo("isdeleted", deleteFlagenum.undelete.getCode());
It is not feasible to use dog.isdeleted
to get the attribute name directly in Java. The Java reflection mechanism can obtain attribute information, but cannot directly provide this syntactic sugar. tk.mybatis itself does not support it.
Solution: Use MyBatis-Plus' LambdaQueryChainWrapper
. It allows the use of Lambda expressions to build query conditions, automatically obtain attribute names, and avoid string stitching.
// Chain query Lambda expressions (Kotlin is not supported) LambdaQueryChainWrapper<t> lambdaQuery(); // Example: lambdaQuery().eq(Dog::getIsdeleted, deleteFlagenum.undelete.getCode()).list();</t>
Dog::getIsdeleted
this way, MyBatis-Plus can automatically identify the isdeleted
attribute name, significantly improving the readability and maintainability of the code, and perfectly solving the problem. Note: LambdaQueryChainWrapper
does not support Kotlin. If using Kotlin, other options need to be considered, such as reflection combined with annotations or custom tool classes.
The above is the detailed content of How to get Java entity class attribute names elegantly to avoid hard-coded in MyBatis queries?. For more information, please follow other related articles on the PHP Chinese website!

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