When can an object reference be cast to an interface reference

An object reference be cast to an interface reference when the object implements the referenced interface. In Java, an object reference can be cast to an interface reference when the object’s class implements that interface. This is possible because Java supports polymorphism through interfaces. Here’s a brief explanation: When the Object Implements the Interface: If … Read more

What is the % operator

It is referred to as the modulo or remainder operator. It returns the remainder of dividing the first operand by the second operand. In Core Java, the % operator is the modulus operator. It is used to find the remainder when one number is divided by another. Here’s an example: java int a = 10; … Read more

How are the elements of a BorderLayout organized

The elements of a BorderLayout are organized at the borders (North, South, East, and West) and the center of a container. In Core Java, the elements of a BorderLayout are organized into five regions: North: Positioned at the top. South: Positioned at the bottom. East: Positioned on the right. West: Positioned on the left. Center: Positioned at … Read more

What is the Dictionary class

The Dictionary class provides the capability to store key-value pairs. In Core Java, as of my last knowledge update in January 2022, there is no built-in Dictionary class in the standard Java API. However, there is a similar class called Hashtable that can be used for key-value pairs. If you are referring to a custom class or … Read more

What is an object’s lock and which object’s have locks

An object’s lock is a mechanism that is used by multiple threads to obtain synchronized access to the object. A thread may execute a synchronized method of an object only after it has acquired the object’s lock. All objects and classes have locks. A class’s lock is acquired on the class’s Class object. In Java, every object … Read more