Java Tutorial: Annotations in java | Java annotations [Built-In Annotations in Java - @retention]

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Java Tutorial: Annotations in java | Java annotations [Built-In Annotations in Java - @retention] 

Java Tutorial: Annotations in java | Java annotations [Built-In Annotations in Java - @retention] 

MultiValueAnnotationDemo.java

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

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
@interface MyMultiValueAnnotation
{
    int getValue() default 2;

    String getMessage() default "hello";
    
    double getDoubleValue() default 5.5;
}

class Message
{
    @MyMultiValueAnnotation
    public void displayHi()
    {
        System.out.println("Hi");
    }
}

public class MultiValueAnnotationDemo
{

    public static void main(String[] args) throws NoSuchMethodException,
            SecurityException
    {
        Message message = new Message();
        Method method = message.getClass().getMethod("displayHi");

        MyMultiValueAnnotation mmva = method
                .getAnnotation(MyMultiValueAnnotation.class);

        System.out.println("value is: " + mmva.getValue());
        System.out.println("message is: " + mmva.getMessage());
        System.out.println("DoubleValue is: " + mmva.getDoubleValue());

    }

}

Output

value is: 2
message is: hello
DoubleValue is: 5.5

Click the below link to download the code:
https://sites.google.com/site/ramj2eev1/home/javabasics/AnnotationDemo_Retention_App.zip?attredirects=0&d=1

Github Link:
https://github.com/ramram43210/Java/tree/master/BasicJava/AnnotationDemo_Retention_App

Bitbucket Link:
https://bitbucket.org/ramram43210/java/src/47d09ebb24294f7b507419345f38ec4cde27d544/BasicJava/AnnotationDemo_Retention_App/?at=master

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