Key points
- Introduction to Programming: The Streams API with Lambda expressions introduced the concept of programming to Java.
- Backward compatibility: Provides compatibility with previous versions, allowing older Java applications to run on Java 8 without any changes.
Java Features
1. Simple and Easy to Learn: Java is used to write powerful yet simple code that resembles C++ and keeps Java application development secure. The learning curve is eased simply due to the lack of complex features like operator overloading and multiple inheritance. Therefore, it is a good choice for beginners and professionals.
2. Compiled and Interpreted: Java code compensates into bytecode, a versatile machineless computer language that is conquered by any system via Java Virtual Machine. The JVM reads this bytecode and interprets it at runtime; so Java can be seen as both compiled (to the bytecode) and interpreted. It leverages both: being Java and optimization of the performance making it run fast as well.
3. Platform Independent: One of Java's robust features is platform independence. Java is converted into a portable executable file (called Java bytecode) that can be executed on any device with the native JVM for its platform. Java became so popular in many industries due to this "write once, run anywhere" characteristic.
4. Portable: Java has become popular because it comes with one platform-independent bytecode. Java programs are compiled to platform-independent byte code which can run on any Java Virtual Machine (JVM). JVM makes sure the bytecode is executed uniformly, irrespective of underlying hardware or operating system.
5. Architectural Neutral: Since Java is not bound to any particular architecture or processor, it is said to be architecturally neutral. The JVM abstracts the details of hardware, that makes it possible to run a Java program on any system. This neutrality is what makes Java applications more flexible and scalable.
6. Object-Oriented: Java as an object-oriented language works with objects and classes to represent entities from the real world. It allows for well-coherent code to facilitate the reusability of this code, its maintenance and modularity. Several of the key object-oriented principles supported over Java are inheritance, encapsulation, polymorphism and abstraction.
7. Robust: Java is known for its robust memory management, which uses automatic garbage collection. An elaborate exception-based error-handling framework that enables developers to write robust code. Java allows us to respawn the same objects, eligible for garbage collection, and another importance is it also removes pointers which are so common generation of errors in C++-like languages.
8. Secure: Java has an extensive security model that addresses numerous possible threats. Through Java sandbox, bytecode verification and cryptographic APIs this language helps to protect applications from unauthorized access and data breaches. So, Java is the best fit for secured and enterprise applications.
9. Distributed: Java is a good choice for creating distributed applications because it includes robust built-in support for networking. Java has inbuilt networking libraries such as RMI (Remote Method Invocation), and support for web services which allow the development of applications that can communicate and work with each other over a network very smoothly.
10. Interactive chaining with concurrency (multi-threading): One of the good built-in support Java provides is for multi-threading which means one program can run simultaneously more than two different parts. This helps Java applications to root multiple tasks or processes at a time — which increases the performance and responsiveness of your app. It automatically handles the thread safety of that interaction by providing synchronization primitives.
11. High Performance: Java compile performance is improved to native machine code by using Just In Time(JIT) compiler. This approach, combined with optimization techniques such as HotSpot is how Java gets its speedy applications. Java uses high-performance garbage collection and memory management to provide better capabilities.
12. Dynamic and Extensible: Java is a dynamically loaded language because we can load a class and library at the same time after runtime. This makes the application capable of adding more features without recompiling them. Java is most effective for applications that constantly update and customise based on evolving environments. It is a highly dynamic language that has sufficient support for reflection and runtime type identification to ensure the full expression of its flexibility.
How is Java Platform Independent?
- Platform independence in Java refers to the ability of Java programs to run on any device or operating system with a Java Virtual Machine (JVM) without requiring any modifications to the code.
- This feature is one of the core strengths of Java and is achieved through a specific process involving compilation and interpretation.
How Platform Independence is Achieved:
1.Java Source Code Compilation:
- When we write a Java program, we write the source code in .java files.
- The Java compiler (javac) then compiles this source code into bytecode, which is stored in .class files. Bytecode is an intermediate, platform-independent representation of our code.
2.Java Bytecode:
- Bytecode is not specific to any particular type of hardware or operating system. It is designed to be executed by the JVM.
- Because bytecode is standardized, it can be understood and executed by any JVM, regardless of the underlying platform.
3.Java Virtual Machine (JVM):
- The JVM is a virtual environment that reads and executes the bytecode.
- Each operating system (Windows, macOS, Linux, etc.) has its version of the JVM, but they all understand and run the same bytecode.
- This means we can write our Java program once, compile it to bytecode, and run that bytecode on any device that has a JVM, without needing to recompile or modify our code.
What is Object Oriented Programming?
- Object-Oriented Programming (OOP) is a programming paradigm centred around the concept of "objects," which are instances of classes. In OOP, a class is a blueprint that defines objects' structure and behavior (attributes and methods). This approach to programming models real-world entities and their interactions, making software design more intuitive and modular.
- Key principles of OOP include encapsulation, inheritance, polymorphism, and abstraction.
- Encapsulation involves bundling data and methods within a class, restricting direct access to some of the object's components.
- Inheritance allows classes to inherit properties and behaviors from other classes, promoting code reuse and hierarchical organization.
- Polymorphism enables objects to be treated as instances of their parent class, allowing methods to perform different functions based on the object they are called on.
- Abstraction hides complex implementation details, exposing only the essential features of an object.
Java, as a prominent object-oriented programming language, fully embraces these principles, enabling developers to create scalable, maintainable, and reusable software. There are two more main types of programming languages, procedural and functional programming languages. Here is a comparison of these programming languages:
| PROCEDURAL PROGRAMMING LANGUAGE | FUNCTIONAL PROGRAMMING LANGUAGE | OBJECT-ORIENTED PROGRAMMING LANGUAGE |
|---|---|---|
| Procedural programming is based on the concept of procedure calls, where programs are structured into procedures or routines. | Functional programming treats computation as the evaluation of mathematical functions and avoids changing state and mutable data. It emphasizes the use of pure functions and immutability. | Object-oriented programming organizes software design around data, or objects, rather than functions and logic. Objects are instances of classes. |
Sequential Execution: The program is executed sequentially, step-by-step. Functions: Focuses on creating reusable procedures (functions) to operate on data. State and Data: Data and state are usually separate from functions; functions can operate on global or passed-in data. | Pure Functions: Functions that have no side effects and return the same result for the same input. Immutability: Data is immutable; once created, it cannot be changed. First-Class Functions: Functions are first-class citizens, meaning they can be passed as arguments, returned from other functions, and assigned to variables. | Encapsulation: Bundling data and methods that operate on the data within objects. Inheritance: Creating new classes from existing ones, promoting code reuse. Polymorphism: Ability to call the same method on different objects and have each object respond in its way. |
| Examples: C, Pascal, BASIC. | Examples: Haskell, Lisp, Erlang, Scala (supports both OOP and FP), and JavaScript (supports FP concepts). | Examples:Java, C++, Python, Ruby. |
Hence, most programming languages are a combination of these three programming languages. For example, Java is procedural, functional as well as object-oriented.
Two-min Drills
- Platform-independent: Write once, and run anywhere with a Java Virtual Machine (JVM).
- Object Management: Focus on real-world objects with basic principles such as inheritance, encapsulation, and polymorphism.
- Automated memory management: Java manages memory through garbage collection, reducing memory leaks.
- Rich API: Extensive libraries include everything from data structures to networking.
- Multithreading: Java supports concurrent programming, enabling multiple tasks to run simultaneously.
- Security: Built-in security features such as bytecode verification and Security Manager protect your applications.
Two-min Drills
- Platform-independent: Write once, and run anywhere with a Java Virtual Machine (JVM).
- Object Management: Focus on real-world objects with basic principles such as inheritance, encapsulation, and polymorphism.
- Automated memory management: Java manages memory through garbage collection, reducing memory leaks.
- Rich API: Extensive libraries include everything from data structures to networking.
- Multithreading: Java supports concurrent programming, enabling multiple tasks to run simultaneously.
- Security: Built-in security features such as bytecode verification and Security Manager protect your applications.