How to use Java annotation to implement code compilation time check

Java annotation can be used to perform static checks during code compilation, which can reduce runtime errors and improve code robustness. The following is a sample code that uses Java annotation to implement code compilation check: Firstly, define a custom annotation class to mark the methods that need to be checked at compile time: import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; @Retention(RetentionPolicy.SOURCE) @Target(ElementType.METHOD) public @interface CheckValue { } Then add the annotation on the method that needs to be checked: public class MyClass { @CheckValue public static void checkStringLength(String value) { if (value.length() > 10) { System.out.println("String length is too long"); } } public static void main(String[] args) { checkStringLength("This string is too long"); } } Compiling the above code will result in a compile time error: MyClass.java:12: error: String length is too long checkStringLength("This string is too long"); ^ 1 error It can be seen that during the compilation process, code logic errors using the 'CheckValue' annotation method were detected and corresponding error prompts were provided. Summary: By using Java annotation, you can perform static checks during code compilation to find code errors in advance and reduce runtime errors. This approach can effectively help developers identify and solve problems during the coding process, improving the reliability and stability of the code. Using annotations for compile time checking can be easily extended and customized, making the code easier to maintain and iterate.