Classes and Objects in Java

What is a Class in Java?

Java's class is a collection of objects with similar attributes. An object is generated using a template or blueprint. The class cannot be tangible, as it is a logical entity. A class in Java can contain:

• Fields
• Methods
• Constructors
• Blocks
• Nested class and interface

Java Class Properties

• Class is not an actual object.
• It is simply a template, blueprint, or prototype from what objects are built.
• Class does not require memory.
• A class consists of variables of various data types as well as methods.

Java Class Components for class declaration

Class declarations can generally include the following components, in this order: 

• Modifiers
• Class keyword
• Class name
• Superclass(if any)
• Interfaces(if any)
• Body

What are Objects in Java?

An object is a stateful entity with behavior, such as a chair or a bike. It may be physical or logical (tangible and intangible).

Characteristics of Objects in Java

An object has 3 characteristics:

1. State
2. Behavior
3. Identity

Different ways to create objects in Java

• Using the new keyword
• Using Class.forName() method
• Using clone() method
• Using object deserialization
• Using Factory Method
• Using Dependency Injection

Java's Anonymous Objects

Anonymous objects, which are created without being stored in a reference variable, are used for direct method calls, which are common in many libraries, and are destroyed after method execution.