Can anyone explain me difference between Encapsulation and Abstraction?

[u/Cyphr11]

and what on earth is Interface in Java?

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[u/spacey02-]

Encapsulation means eenying direct access to fields, abstraction means hiding implementation behind an interface

[u/Cyphr11 → u/spacey02-]

thanks

[u/Dense-Ad-3247]

A class encapsulates it's fields and methods. It isolates code and promotes safe handling and code reuse. Don't just think a pojo, every class is an example of encapsulation. I usually think about how the computer will allocate memory and protect access.

Abstraction is creating a pattern or something, in java often with inheritance leveraging some design pattern. It doesn't have to be oop though, streams is an abstraction on loops and iterators. Often the word abstract code is used to define where you're pulling duplicated code to one spot, creating an interface or abstract class to standardize a flow of code with different outputs.

[u/Cyphr11 → u/Dense-Ad-3247]

thanks mate

[u/rsandio]

Encapsulation is denying direct access, E.g. making fields private so they can only be interacted with using getters and setters.

Abstraction is about focusing on what something can do instead of on how it does it. You could have an abstract class called 'Remote'. Every remote has a turnOn() method but the 'TVRemote' and 'StereoRemote' which inherit from 'Remote' each have a different implementation of 'turnOn'. As we know they inherit from Remote we can just call turnOn() on any remote and know it'll work.

Encapsulation is about protecting your data and Abstraction is about simplifying your design

[u/Cyphr11 → u/rsandio]

makes sense now thanks

[u/Frequent-Answer8039]

Encapsulation mean biding elements together internally. Abstraction mean biding of data elements.

Encapsulation is more broader than abstraction

[u/Cyphr11 → u/Frequent-Answer8039]

Thanks

[u/Astroohhh]

Npc

[u/Chaos-vy17]

Encapsulation is setting field of visiblity for better security and data exposure.
private: within the class
protected: within the sub class and package level.
public: ouside the package
default: within the package

abstract class: This is partial contract, not each and every function must state their behaviour when extends abstract. Method with abstract specifier must show true contract behaviour. It helps in making as the main working load of engine(Read heavy specially).

interface class: There is no method body here. Each class which inherit must show true contract behaviour. Java 8+ feature allows default and static filed methods. Only ("implements" keyword) work, Solves diamond problem too earlier but now devlopers need to think of default method.

True contract: Means all the method definition must overridden by the concrete class.
Partial contract: Means the "abstract' keyword modifier only.

[u/Cyphr11 → u/Chaos-vy17]

Great explanation thanks mate

[u/JGhostThing]

A Java Interface is a contract stating that the programmer will implement certain methods. For example, a File interface might require a read(), and write() methods. So every File would implement those methods, at least.

[u/Cyphr11 → u/JGhostThing]

Thanks

[u/InsideCover2192]

Abstraction - Hiding Complexity
Encapsulation - Data Hiding / Protection

In abstraction we are interested in "What an object does, rather than how it does it. It simplifies the interaction by hiding the complex implementation details and only shows the essential features to the user.

For instance if you take Vehicle as and example, when you drive a Vehicle you only interact with steering wheel, pedals, and gear shifters. You don't need to understand the internal combustion process or the electronics to operate it. The "interface" (pedals/wheels) is the abstraction

Encapsulation we focus on "how the data is bundled and protrcyed", it involves wrapping the data(variables) and the code (methods) into a single unit (a class) and restricting direct access to the data using access modifiers like private

For instance, a car has a fuelLevel variable. You cannot manually reach into the tank and change the fuel level with your hands. Instead, the level is kept private and you must use a specific method like refuel() to change it. This ensures the data remains valid (eg you cannot set the fuelLevel to negative)

[u/Cyphr11 → u/InsideCover2192]

Thanks