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AnnotatedElement getAnnotationsByType() method in Java with Examples

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The getAnnotationsByType() method of java.lang.AnnotatedElement class is used to get the annotations of the specified annotation type present in the class implementing this interface. The method returns an array of annotations for the specified annotation type.

Syntax:

public A[] getAnnotationsByType(Class<T> annotationClass)

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

Return Value: This method returns an array of annotations for the specified annotation type.

Exception: This method throws:

  • NullPointerException: if the given annotation class is null.

Below programs demonstrate the getAnnotationsByType() method.

Example 1:




// Java program to demonstrate
// getAnnotationsByType() method
  
import java.util.*;
import java.lang.reflect.*;
import java.lang.annotation.*;
  
// create a custom Annotation
@Retention(RetentionPolicy.RUNTIME)
@interface Annotation {
  
    // This annotation has two attributes.
    public String key();
  
    public String value();
}
  
// call Annotation for method
// and pass values for annotation
@Annotation(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 annotation
        // using getAnnotationsByType() method
        System.out.println(
            "Annotation of myAnnotatedElement"
            + " of type Annotation: "
            + Arrays.toString(
                  myAnnotatedElement
                      .getAnnotationsByType(
                          Annotation.class)));
    }
}


Output:

AnnotatedElement represented by myAnnotatedElement: class Test
Annotation of myAnnotatedElement of type Annotation: [@Annotation(key=GFG, value=GeeksForGeeks)]

Example 2:




// Java program to demonstrate
// getAnnotationsByType() method
  
import java.util.*;
import java.lang.reflect.*;
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 myAnnotatedElement
            AnnotatedElement myAnnotatedElement
                = Test.class;
  
            System.out.println(
                "AnnotatedElement represented"
                + " by myAnnotatedElement: "
                + myAnnotatedElement.toString());
  
            // Get the annotation
            // using getAnnotationsByType() method
            System.out.println(
                "Annotation of myAnnotatedElement"
                + " of type Deprecated: "
                + Arrays.toString(
                      myAnnotatedElement
                          .getAnnotationsByType(
                              Deprecated.class)));
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}


Output:

AnnotatedElement represented by myAnnotatedElement: class Test
Annotation of myAnnotatedElement of type Deprecated: [@java.lang.Deprecated()]

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



Last Updated : 03 Jan, 2020
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