What is Java?

Java is a popular programming language owned by oracle and more than 3 billion devices run java. Use for application development, game, and much more.

Advantages of Java

1. Simple

2. Object-Oriented (OO)

3. Platform Independent | Architecturally Neutral | Portable

4 Secure

5. Dynamic and Distributed

6. Robust

7. Multithreaded

8. Internationalization

1. Simple

~ Syntax is similar to C/C++

~ Pointer management, and memory management, need not be managed by developers.

2. Object-Oriented

Procedural programming is about writing procedure to perform some action on data while object-oriented programming is about creating an object which contains both methods and data, which makes it more relatable with the real world.

Advantages of Object-Oriented Programming (OOP)

* Easy to meet project/customer/other requirements

* Easy Maintainability

* Easy Enhance ability

3. Platform Independent

Compiled Java code is platform-independent mean it is independent of Operating systems and Hardware.

Note:

JDK(Java Development Kit) contains: JVM + Javac + rt.lib + developer tools

where,

JVM: Java Virtual Machine which converts compiled java code also known as Byte Code(FileName.class) to machine code with the help of an interpreter.

Bytecode(FileName.class) => JVM =>Machine code.

*The bytecode is platform-independent whereas machine code is platform dependent.

Javac-: Java Compiler compiles java file to bytecode.

FileName.java => javac => Bytecode

rt. lib-: Runtime library contains Operating System Calls.

Developer tools-: Contain various development tools.

* Difference between Compiler and interpreter are

- Compiler convert the whole code at once while the interpreter does a line by line conversion.

-Compiler never executes code while the interpreter executes code.

* Java developer gives bytecode to their customer and using JRE (Java Runtime Environment) customers run the code on their device.

JRE contains : JVM + rt.lib

-JDK always have JRE.

4. Secure

- Authorized and Authenticated code, which will never harm the device.

-Encryption and Decryption all the code given to customers are encrypted.

5. Dynamic and Distributed

Dynamic: It can invoke other Java Program

Distributed: Invoke program running on, other machines too.

6. Robust

There are fewer bugs in the java program because there is no pointer and memory management.

7. Multithreaded

It is a JVM feature in Java Environment that allows multitasking.

8. Internationalization

All the terminologies of Java Environment are standardized and universally accepted.

Note:

OOS(Object-Oriented System): A bunch of objects interacting with each other to satisfy a request.

OOP(Object-Oriented Programming): Set of instruction to create an object and make them interact.

OOPL(Object-Oriented Programming Language): A programming language with Syntax and semantic using which we can construct an OOP.

OOD(Object-Oriented Design): Process of designing objects.