Day087

README.adoc

@@ -3237,4 +3237,42 @@ public class Day086 {
         }
     }
 }
+----
+
+== Day 87 - Verifying if a class is annotated by a particular annotation.
+[source,java]
+----
+package com.thegreatapi.ahundreddaysofjava.day087;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+public class Day087 {
+
+    public static void main(String[] args) {
+        var myAnnotatedObject = new AnnotatedClass();
+        var myNonAnnotatedObject = new NonAnnotatedClass();
+
+        System.out.println(isAnnotated(myAnnotatedObject));   // Prints: true
+        System.out.println(isAnnotated(myNonAnnotatedObject)); // Prints: false
+    }
+
+    private static boolean isAnnotated(Object object) {
+        return object.getClass().isAnnotationPresent(MyAnnotation.class);
+    }
+
+    @MyAnnotation
+    static class AnnotatedClass {
+    }
+
+    static class NonAnnotatedClass {
+    }
+
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.TYPE)
+    @interface MyAnnotation {
+    }
+}
 ----

days/day087/pom.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>days</artifactId>
+        <groupId>com.thegreatapi.100daysofjava</groupId>
+        <version>1.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>day087</artifactId>
+
+    <properties>
+        <maven.compiler.source>16</maven.compiler.source>
+        <maven.compiler.target>16</maven.compiler.target>
+    </properties>
+
+</project>

days/day087/src/main/java/com/thegreatapi/ahundreddaysofjava/day087/Day087.java

@@ -0,0 +1,33 @@
+package com.thegreatapi.ahundreddaysofjava.day087;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+public class Day087 {
+
+    public static void main(String[] args) {
+        var myAnnotatedObject = new AnnotatedClass();
+        var myNonAnnotatedObject = new NonAnnotatedClass();
+
+        System.out.println(isAnnotated(myAnnotatedObject));   // Prints: true
+        System.out.println(isAnnotated(myNonAnnotatedObject)); // Prints: false
+    }
+
+    private static boolean isAnnotated(Object object) {
+        return object.getClass().isAnnotationPresent(MyAnnotation.class);
+    }
+
+    @MyAnnotation
+    static class AnnotatedClass {
+    }
+
+    static class NonAnnotatedClass {
+    }
+
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.TYPE)
+    @interface MyAnnotation {
+    }
+}

days/pom.xml

@@ -97,6 +97,7 @@
         <module>day084</module>
         <module>day085</module>
         <module>day086</module>
+        <module>day087</module>
     </modules>
 
 </project>