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Basic concepts of Java

Hello readers, Beauty James here again with another exciting article. I’ve been talking about Frontend development for some time now so I’ll be considering Java, one of the many examples of programming languages used for Frontend development. I will be discussing the following headings below;
• What is Java?
• History of Java programming language
• Java Features
• Java Architecture
• Components of Java Programming language
• What is Java Platform?
• Types of Java Platforms
• How is Java Platform Independent?
• Uses and applications of Java

What is Java?
Java is a high level class based object oriented programming language designed to have just a few implementation dependencies. It is a multi platform and a network centric language. As other programming languages, it is a platform for application development. Java codes can be Compiled to byte codes to run on all platforms supporting java without recompilation. Java is particularly popular for its client-sever web applications with more than 9 million developers under their belt.

History of Java Programming Language
Java, originally called oak was developed in the early 1990s by James Gosling and 4 other developers at Sun Microsystems, Inc. (later acquired by oracle in 2009) and released in 1995. At the time, the internet and the WWW were becoming more and more popular but the C and C++ programs used were not platform independent (they had to be compiled and recompiled for different hardware and processors) and required more memory. So the 5 developers sought to create a language that could run on any operating system regardless of the systems hardware or software configuration. The program used for java is small and portable and could be transported over any network. This new development attracted developers in no time because it also allows communication between consumer electronics, making Java the most popular programming languages to this time. Although James Gosling developed java in the early 1990s, he left the company after its acquisition in 2009 by Oracle Corporation to work with Amazon web services.

Features of Java
• Object oriented: Java is a fully object oriented language and possesses features such as encapsulation, polymorphism, inheritance, abstraction, class and object.

• Robust: With features such as automatic Garbage Collection and Exception handling, it helps programmers to create reliable applications which eliminates error prone codes.

• Simple: The language is easy to learn and the syntax is clean and easily understandable.

• Security: Java programs run in Java Runtime Environment (JRE) which makes little or no interaction with the Operating System, making the program free from virus attacks because it can’t be invaded from the outside.

• Multi-threading: Java makes use of multi threading features which makes it possible to execute multiple tasks at the same time, resulting in highly interactive and responsive applications.

• High Performance: Since Java cannot be as fast as C or C++, it makes use of a Java compiler which changes java codes into bytecodes so java applications can run at full speed.

• Independence: Any machine with Java Runtime Environment can run Java programs because all java programs are compiled into bytecode which is platform Independent.

Java Architecture
Java Architecture compiles and interprets a program. It explains the process involved in formulating a Java program which includes converting the codes written in java into byte codes, which is done by the Java Compiler. The byte codes are then converted into machine code by the JVM (Java Virtual Machine) which is executed directly by the machine.

Components of Java
There are three main components of Java language.
• Java Virtual Machine (JVM): This is a component that gives developers an environment to execute Java programs by converting byte codes into machine codes. JVM, first of all, loads the code into memory and verifies it. After that, it executes the code and provides a runtime environment. Hence, JVM performs actions in this order: loads the java codes, verifies them, executes them, and then provides a runtime environment for the codes.

• Java Runtime Environment (JRE): JRE builds a runtime environment in which Java programs can be executed. It is located on the on-disk system which takes the Java code, combines it with the needed libraries, and starts the JVM to execute it. JRE contains libraries and software that your Java programs need to run. JRE is a part of JDK.

• Java Development Kit: JDK is a software development environment used to develop Java applications and applets. It contains development tools such as an interpreter/loader (java), a compiler (javac), an archiver (jar), a documentation generator (javadoc).

Java Platforms
A platform is a hardware or software environment in which a program runs. Java has its own run time environment known as JRE(Java Run-time Environment) and Java Virtual Machine(JVM) which converts Java codes to machine codes, making it possible to develop and run the programs that are written in Java Programming language. Java platforms includes execution engine, compiler and set of libraries.

Types of Java Platforms
By the late 1990s, Java grew beyond the World Wide Web and as a result, Sun Microsystems created varieties of Java for different purposes, also known as Java editions, such as:
• Java platform Standard Edition: Java Standard Edition is a computing platform that targets work station environments, offering the Java programming language’s core functionality. It is used for the development and deployment of portable codes used in desktop and server environments. It is also used in networking, security, database access, Graphical User Interface (GUI) development, and XML parsing.

• Java platform Enterprise Edition: is a set of specifications that targets large distributed enterprises or internet environments with features such as distributed computing and web services. The application runs on reference runtimes which handles transactions, security, scalability, concurrency and the management of components to be deployed. Applications of Java Platform Enterprise include e-commerce, accounting, banking information systems.

• Java Platform Micro Edition: This is a computing platform used for the development and deployment of portable codes for embedded and mobile devices like micro-controllers, sensors, gateways, mobile phones, printers, etc.

• Java FX: JavaFX is used for creating desktop applications and Rich Internet Applications(RIAs) which can run on a wide variety of devices including desktop computers and web browsers. Its user hardware-accelerated graphics and media engines helps Java take advantage of higher-performance clients and high-level APIs for connecting to networked data sources.

How is Java Platform Independent?
A platform can be called independent if it can run on all available Operating Systems with respect to its development and compilation. Now, Java is platform-independent simply because it produces a unique format called bytecode. First, source code is used by Java compiler and is converted in class file. The class file code is in byte code form and that class file is used by JVM to convert it into an object file. After that, you can see the final output on your screen. Any machine with Java Runtime Environment can run Java Programs. In short, the Java source code can run on all operating systems. Therefore, Java is a platform-Independent language.

Uses and Applications of Java
• Mobile App development: Java is supported by Android Studio which helps facilitate secure and efficient development for a wide range of mobile applications. It becomes much easier for developers to develop android applications such as Spotify and twitter with the use of Java.

• Game development: Java is often used by game development companies because of its support for the open-source most powerful 3D engine which provides unequalled capacity in designing 3D games. The most popular games developed using Java are Minecraft, Mission Impossible III, etc. Bear in mind that some developers avoid developing games using Java because of its garbage-collection issues, which results in performance problems and frequent pausing in the apps. It is riskier to use Java for the development of bigger AAA games due to this very problem.

• Cloud based Applications: A cloud application is an application that involves data processed on a cloud server. Thanks to factors like top-notch performance, scalability, and reliability, Java has been able to provide the environment to develop cloud-based applications, providing low cost services to its users. There are many types of services that use cloud computing, with the aid of cloud apps like Dropbox, Amazon Web Services, Slack, and Salesforce for storage and file-sharing purposes. Gmail, for instance, is an example of a cloud-based application built with Java.

• IoT devices: IoT is a technology that connects the devices in its network and communicates with them without human intervention. Combined with technologies like Artificial Intelligence (AI), Java can help power devices remotely, connect appliances and other objects through devices such as health gears, smartphones, wearables, smart lighting, TVs, etc. The IoT is also applied in many industries, including healthcare, security, supply-chain management, and others. IoT programmers gravitate towards Java because it is secure, flexible, and versatile.

• Web applications: Web application development was one of the first uses of Java and it still remains a first choice language for this because of its security, scalability, and high performance. Due to these factors, many businesses, large and small, turn to Java when they are looking for a quick turnaround for a high-performance web application. Using this technology, users can develop a variety of applications such as LinkedIn, AliExpress,, IRCTC, etc.

• Scientific applications: Fields like healthcare and research use Scientific applications frequently to integrate and use math to perform practical, real-world computations, and calculations. Java is often used for creating these apps because they depend on accuracy, reliability, security and not to mention high performance. They can access plenty of support and receive help with troubleshooting.

• Enterprise Applications: This software is often used for enterprises (large businesses) that need streamlined services delivered in one place because it connects and gives access to various departments and employees. There is also an entire set of Java Application Programming Interfaces (APIs) for enterprises called Java Platform, Enterprise Edition (Java EE) that facilitates efficient and easy scripting. Its platform independence supports company-wide integration and compatibility, making delivery more convenient. Scalability in Java also makes it easier for growing enterprises to keep up with their efforts.

• GUI applications: GUI applications can also be developed using Java because it provides frameworks such as AWT, JavaFX, and Swing which enables developers to design, create, test, debug, and deploy Rich Client Applications (RIAs) that behave consistently across multiple platforms.

At this point, readers should be able to understand the basic concepts of Java such as its definition, architecture, features, components, platforms and its applications. Note that Java is not the same as JavaScript although they are often compared to each other. Java is a programming language that creates applications that run in a virtual machine or a browser while Java Script is a scripting language that runs on a browser only.
These are some of the core upgrades done as a part of Java 8 and 11 release respectively:
• Ease of Use
• Increased productivity by providing Optional Classes feature, Lambda Expressions, Streams etc.
• Improved Polyglot programming (performs the same operations in multiple programming languages).
• Improved Security and performance.
Java 11;
• Standardized http client
• Lazy Allocation of Compiler Threads
• Enhanced KeyStore Mechanisms
• Updated Locale Data to Unicode CLDR v33
• JEP 331 Low-Overhead Heap Profiling
• Includes support for Unicode 10.0.0
• JEP 330 Launch Single-File Source-Code Programs
• JEP 181 Nest-Based Access Control
• Added Brainpool EC Support (RFC 5639)
• JEP 332 Transport Layer Security (TLS) 1.3

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