java 13 interview questions and answers

The ActionEvent event is generated as the result of the clicking of a button. In Core Java, when a button is clicked, the corresponding event is typically handled by an ActionListener. The ActionListener interface provides a way to respond to events triggered by user interactions, such as button clicks. The correct answer to the question “What event … Read more

The java.util.EventObject class is the highest-level class in the event-delegation class hierarchy. In the Java event-delegation model, the highest-level event class is java.util.EventObject. This class is the root class for all event classes in the Java AWT (Abstract Window Toolkit) and Swing libraries. Events in Java are based on the observer design pattern, where an event source … Read more

A class is a subclass of itself. In Java, a class is not a subclass of itself. Inheritance in Java involves creating a new class based on an existing class, and the new class is referred to as the subclass. The existing class is known as the superclass. A subclass inherits attributes and behaviors from … Read more

An interface may be declared as public or abstract In Core Java, an interface declaration can have the following modifiers: public: An interface can be declared as public, which means it can be accessed from other packages. abstract: Interfaces are implicitly abstract; you don’t need to use the abstract keyword explicitly. However, if you do use it, it … Read more

During compilation, the values of each case of a switch statement must evaluate to a value that can be promoted to an int value. In Java, there are certain restrictions on the values that can be used in each case of a switch statement. Here are the key points: Must be a Constant Expression: The values used in each … Read more