A NullPointerException (NPE) in Java is an unchecked runtime exception that occurs when an application attempts to use an object reference that points to null in memory. In Java, null signifies the absence of an instantiated object. When the Java Virtual Machine (JVM) tries to dereference null—such as invoking an instance method, accessing a field, or indexing through an … [Read more...] about Fix NullPointerException in Java (AP CSA Guide)