The isAnnotationPresent() method of java.lang.AnnotatedElement class is used to check if an annotation of the specified annotation type is present in the class implementing this interface. The method returns a boolean value stating the same.
Syntax:
public boolean isAnnotationPresent(Class<T> annotationClass)
Parameter: This method accepts a parameter annotationClass which is the type of the annotation to get.
Return Value: This method returns boolean value stating the same.
Exception: This method throws:
- NullPointerException: if the given annotation class is null.
Below programs demonstrate the isAnnotationPresent() method.
Example 1:
// Java program to demonstrate// isAnnotationPresent() 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 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());          // Check if there is any annotation        // using isAnnotationPresent() method        System.out.println(            "If there is any annotation"            + " in myAnnotatedElement: "            + myAnnotatedElement                  .isAnnotationPresent(                      Annotation.class));    }} |
AnnotatedElement represented by myAnnotatedElement: class Test
If there is any annotation in myAnnotatedElement: true
Example 2:
// Java program to demonstrate// isAnnotationPresent() method  import java.util.*;import java.lang.reflect.*;import java.lang.annotation.*;  // Class with no annotationspublic class Test {      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 isAnnotationPresent() method        System.out.println(            "If there is any annotation"            + " in myAnnotatedElement: "            + myAnnotatedElement                  .isAnnotationPresent(                      Annotation.class));    }} |
AnnotatedElement represented by myAnnotatedElement: class Test
If there is any annotation in myAnnotatedElement: false
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