How to get Java entity class attribute names elegantly to avoid hard-coded in MyBatis queries?

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.

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