AnnotatedElement getDeclaredAnnotation() method in Java with Examples

The getDeclaredAnnotation() method of java.lang.reflect.AnnotatedElement interface is used to get the declared annotation of the specified declared annotation type, if such an declared annotation is present in the class implementing this interface. 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 implementing this interface.

Exception: This method throws:

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

Below programs demonstrate the getDeclaredAnnotation() method.

Example 1:

// Java program to demonstrate
// getDeclaredAnnotation() method

import java.util.*;
import java.lang.annotation.*;
import java.lang.reflect.*;

// 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 myAnnotatedElement
        AnnotatedElement myAnnotatedElement
            = Test.class;

        System.out.println(
            "AnnotatedElement represented"
            + " by myAnnotatedElement: "
            + myAnnotatedElement.toString());

        // Get the declared annotation
        // using getDeclaredAnnotation() method
        System.out.println(
            "DeclaredAnnotation of myAnnotatedElement: "
            + myAnnotatedElement
                  .getDeclaredAnnotation(
                      DeclaredAnnotation.class));
    }
}

Output:

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

Example 2:

// Java program to demonstrate
// getDeclaredAnnotation() method

import java.util.*;
import java.lang.annotation.*;
import java.lang.reflect.*;

@Deprecated
public class Test {

    public Object obj;

    public static void main(String[] args)
        throws ClassNotFoundException
    {
        try {

            // returns the Class object
            // for this myAnnotatedElement
            AnnotatedElement myAnnotatedElement
                = Test.class;

            System.out.println(
                "AnnotatedElement represented"
                + " by myAnnotatedElement: "
                + myAnnotatedElement.toString());

            // Get the declared annotation
            // using getDeclaredAnnotation() method
            System.out.println(
                "DeclaredAnnotation of myAnnotatedElement: "
                + myAnnotatedElement
                      .getDeclaredAnnotation(
                          Deprecated.class));
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

Output:

AnnotatedElement represented by myAnnotatedElement: class Test
DeclaredAnnotation of myAnnotatedElement: @java.lang.Deprecated()

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