Class getDeclaredAnnotation() method in Java with Examples

The getDeclaredAnnotation() method of java.lang.Class class is used to get the declared annotation of the specified declared annotation type, if such an declared annotation is present in this class. The method returns that class in the form of an object.

Syntax:

public T getDeclaredAnnotation(Class<T> declared annotationClass)

Parameter: This method accepts a parameter declared annotationClass which is the type of the declared annotation to get.

Return Value: This method returns the specified object of the declared annotation class.

Exception: This method throws:



  • NullPointerException: if the given declared annotation class is null.

Below programs demonstrate the getDeclaredAnnotation() method.

Example 1:

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate
// getDeclaredAnnotation() method
  
import java.util.*;
import java.lang.annotation.*;
  
// create a custom DeclaredAnnotation
@Retention(RetentionPolicy.RUNTIME)
@interface DeclaredAnnotation {
  
    // This declared annotation has two attributes.
    public String key();
  
    public String value();
}
  
// call DeclaredAnnotation for method
// and pass values for declared annotation
@DeclaredAnnotation(key = "GFG", value = "GeeksForGeeks")
public class Test {
  
    public Object obj;
  
    public static void main(String[] args)
        throws ClassNotFoundException
    {
  
        // returns the Class object for this class
        Class myClass = Test.class;
  
        System.out.println(
            "Class represented by myClass: "
            + myClass.toString());
  
        // Get the declared annotation
        // using getDeclaredAnnotation() method
        System.out.println(
            "DeclaredAnnotation of myClass: "
            + myClass
                  .getDeclaredAnnotation(
                      DeclaredAnnotation.class));
    }
}

chevron_right


Output:

Class represented by myClass: class Test
DeclaredAnnotation of myClass: @DeclaredAnnotation(key=GFG, value=GeeksForGeeks)

Example 2:

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate
// getDeclaredAnnotation() method
  
import java.util.*;
import java.lang.annotation.*;
  
@Deprecated
public class Test {
  
    public Object obj;
  
    public static void main(String[] args)
        throws ClassNotFoundException
    {
        try {
            // returns the Class object for this class
            Class myClass = Test.class;
  
            System.out.println(
                "Class represented by myClass: "
                + myClass.toString());
  
            // Get the declared annotation
            // using getDeclaredAnnotation() method
            System.out.println(
                "DeclaredAnnotation of myClass: "
                + myClass
                      .getDeclaredAnnotation(
                          Deprecated.class));
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

chevron_right


Output:

Class represented by myClass: class Test
DeclaredAnnotation of myClass: @java.lang.Deprecated()

Reference: https://docs.oracle.com/javase/9/docs/api/java/lang/Class.html#getDeclaredAnnotation-java.lang.Class-

Don’t stop now and take your learning to the next level. Learn all the important concepts of Data Structures and Algorithms with the help of the most trusted course: DSA Self Paced. Become industry ready at a student-friendly price.




My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.