Hello Learner English Educator Interview Questions and Answers

Abstract class is a class that cannot be instantiated and interface is a blueprint of a class.

• Abstract class can have both abstract and non-abstract methods while interface can only have abstract methods.

• A class can implement multiple interfaces but can only inherit from one abstract class.

• Abstract class can have constructors while interface cannot.

• Example of abstract class: Animal (cannot be instantiated) and Dog (inh...read more

Java does not support multiple inheritance to avoid the diamond problem and maintain simplicity.

• Multiple inheritance can lead to the diamond problem where a class inherits from two classes with a common parent.

• This can cause ambiguity and conflicts in method and variable resolution.

• Java supports multiple interface inheritance to achieve similar functionality.

• Maintaining simplicity and avoiding complexity is a core prin

Chained Exception is an exception that is caused by another exception.

• It is a way of propagating exceptions through layers of code.

• It helps in identifying the root cause of an exception.

• It can be created by passing the original exception as a parameter to a new exception.

• It can be caught and handled at any level of the code.

• Example: SQLException is caused by a network error, which is caused by a firewall issue.

The exception hierarchy is the order in which exceptions are caught and handled in a program.

• Exceptions are caught and handled in a specific order, with more specific exceptions being caught before more general ones.

• The hierarchy typically starts with the most specific exceptions and ends with the most general ones.

• For example, in Java, the hierarchy starts with checked exceptions, followed by unchecked exceptions, and