Generate me a video that explain clearly on the concept of object and class in java, then in the second section of the video, the video that explains clearly on the concept of Encapsulation, Inheritance, Polymorphism, Abstraction and Interface in Java.

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Welcome to Java Object-Oriented Programming! In this video, we'll explore the fundamental concepts of objects and classes. Object-Oriented Programming, or OOP, is a programming paradigm that organizes code around objects and classes. Java is built on these OOP principles, making it essential to understand these concepts. A class serves as a blueprint or template that defines the structure and behavior of objects. From one class, we can create multiple objects, each being an instance of that class. Now let's look at a concrete example of a Java class. Here we have a Dog class that demonstrates the basic structure. The class contains attributes like name and age, which represent the data or state of a dog object. It also has methods like bark and eat, which define the behaviors that a dog can perform. To create an actual dog object from this class, we use the new keyword followed by the class name. This creates an instance of the Dog class that we can then use in our program. Now let's explore two fundamental OOP principles: Encapsulation and Inheritance. Encapsulation is about bundling data and methods together while hiding internal implementation details. We use private access modifiers to protect data and public methods to provide controlled access. Inheritance allows one class to acquire properties and methods from another class using the extends keyword. Here we see an Animal parent class with an eat method. The Dog and Cat classes inherit from Animal, gaining the eat method while adding their own specific behaviors like bark and meow. Let's explore Polymorphism and Abstraction. Polymorphism means one interface with multiple implementations. Through method overriding, subclasses can provide their own specific implementations of methods defined in the parent class. Here we see an abstract Shape class that defines a common structure with an abstract calculateArea method. Circle and Rectangle classes extend Shape and provide their own implementations of calculateArea. This allows us to treat different shapes uniformly while each executes its specific calculation method. Finally, let's explore Interfaces. Interfaces define contracts that classes must follow, containing abstract methods that implementing classes must provide. Unlike inheritance which creates an 'is-a' relationship, interfaces represent a 'can-do' relationship. Here we see a Swimmable interface with a swim method. Both Fish and Duck classes implement this interface, each providing their own swim implementation. Interfaces enable multiple inheritance of behavior, promote loose coupling, and support polymorphism. This completes our overview of Java's core OOP concepts that form the foundation of robust application design.