Core java Tutorial || Introduction to Java and OOPs|| video-7 || Java Memory Diagram part 3

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Java Memory Diagram
Object Oriented Programming
Object and Class relationship diagram


What we had covered so far::
What is an object in Java
object in Java
An entity that has state and behavior is known as an object e.g., chair, bike, marker, pen, table, car, etc. It can be physical or logical (tangible and intangible). The example of an intangible object is the banking system.

An object has three characteristics:

State: represents the data (value) of an object.
Behavior: represents the behavior (functionality) of an object such as deposit, withdraw, etc.
Identity: An object identity is typically implemented via a unique ID. The value of the ID is not visible to the external user. However, it is used internally by the JVM to identify each object uniquely.

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For Example, Pen is an object. Its name is Reynolds; color is white, known as its state. It is used to write, so writing is its behavior.

An object is an instance of a class. A class is a template or blueprint from which objects are created. So, an object is the instance(result) of a class.

Object Definitions:

An object is a real-world entity.
An object is a runtime entity.
The object is an entity which has state and behavior.
The object is an instance of a class.

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What is a class in Java
A class is a group of objects which have common properties. It is a template or blueprint from which objects are created. It is a logical entity. It can't be physical.

A class in Java can contain:

Fields
Methods
Constructors
Blocks
Nested class and interface

Instance variable in Java
A variable which is created inside the class but outside the method is known as an instance variable. Instance variable doesn't get memory at compile time. It gets memory at runtime when an object or instance is created. That is why it is known as an instance variable.

Method in Java
In Java, a method is like a function which is used to expose the behavior of an object.

Advantage of Method
Code Reusability
Code Optimization
new keyword in Java
The new keyword is used to allocate memory at runtime. All objects get memory in Heap memory area.

Your Queries -

Java Memory Diagram
Object Oriented Programming
Object and Class relationship diagram
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