How do you use runtime retention policies with a simple code example?

An overview of using Java annotations with runtime retention policies, showcasing how they can be applied in a simple example.

Java, annotations, runtime retention policies, programming, example


        import java.lang.annotation.Retention;
        import java.lang.annotation.RetentionPolicy;
        import java.lang.annotation.Target;
        import java.lang.annotation.ElementType;

        // Define a custom annotation with runtime retention policy
        @Retention(RetentionPolicy.RUNTIME)
        @Target(ElementType.METHOD)
        public @interface MyCustomAnnotation {
            String value();
        }

        public class MyClass {

            @MyCustomAnnotation("This is a custom annotation")
            public void myAnnotatedMethod() {
                System.out.println("This method is annotated with MyCustomAnnotation.");
            }

            public void invokeAnnotation() {
                try {
                    // Accessing the annotation at runtime
                    MyCustomAnnotation annotation = this.getClass()
                            .getMethod("myAnnotatedMethod")
                            .getAnnotation(MyCustomAnnotation.class);
                    if (annotation != null) {
                        System.out.println("Annotation value: " + annotation.value());
                    }
                } catch (NoSuchMethodException e) {
                    e.printStackTrace();
                }
            }

            public static void main(String[] args) {
                MyClass myClass = new MyClass();
                myClass.invokeAnnotation();
            }
        }

How do you use runtime retention policies with a simple code example?

Popular Topics

Recent Languages

How do you use runtime retention policies with a simple code example?

Related Questions

Popular Topics

Recent Languages