What is Java?

Java is a programming language and computing platform first introduced in 1995 by Sun Microsystems. Java is a general-purpose, object-oriented, class-based programming language with fewer implementation dependencies. Java is an extensively used program based on object-oriented programming and a software platform used across various devices, such as notebook computers, mobile phones, game consoles, medical gadgets, and many more. Java is quick as well as secure, and reliable, consequently. It is used extensively to create Java applications for laptops, data centres, game consoles, scientific supercomputers, cell phones, etc.

History of Java

James Gosling invented the Java language at Sun Microsystems in 1995. He had a motto: “Write Once; Run Anywhere.” known as WORA. Gosling first named this language Oak because of the oak tree outside his office. The name was later changed to Green and Java Coffee, named after the coffee from Indonesia, and eventually shortened to Java in 1995.

What is Java used for?

Java allows you to create applications for a range of platforms. Servers, desktops, tablets, mobile phones, TVs, Blu-ray players, and web browsers are all based on Java, and developers can develop Java-based software that works on any platform. Because Java is compatible with WORA specifications, the same program can be used across all platforms with Java Runtime Environment (JRE) without rebuilding the code.

Java can be used to write applications for various JRE devices and support apps that can run only on one device, such as a desktop computer or mobile phone. Java can also be used to write applications that operate in a distributed way. This means the same program can be distributed across clients and servers within the network and executed synchronously.

Java Platforms / Editions

There are four platforms or editions of Java:

1) Java SE (Java Standard Edition)

It is a Java software platform for programming. It contains Java programming APIs like Java.lang, java.io, java.net, Java.util, java.sql, java.math, and many more. It covers the most important topics such as OOPs strings, Regex, Exception, Multithreading, Inner Classes, Networking, I/O Stream, Reflection, AWT, Swing, and Collection, among others.

2) Java EE (Java Enterprise Edition)

The platform is an enterprise one, which is used to build enterprise and web applications. It is built upon Java SE. Java SE platform. It encompasses topics like Servlet, JSP, Web Services, EJB, JPA and many more.

3) Java ME (Java Micro Edition)

It is a micro platform that is dedicated to mobile applications.

4) JavaFX

It is used to develop rich internet applications and uses a lightweight user interface API.

Components of Java

There are three main components of the Java programming language, including:

1. JVM: Java Virtual Machine (JVM) is an independent platform Java component that provides a framework for running Java programs. Thus, JVM loads the code and is responsible for validating the code after converting the Bytecode into Machine code to run on different Operating Systems like Windows, Linux, and Mac iOS. It then executes the code and offers an environment for running the program.

    

2.  JRE: Java Runtime Environment (JRE) creates an environment in which Java files can be executed and run. It is a software package that includes JVM, Java class libraries, and a Java loading of classes. In other words, it describes the minimum requirements to run a Java application by containing the necessary libraries and other files.

    

3. JDK: Java Development Kit (also known as JDK) is a variant of JRE and a development environment for creating Java applets and applications. The JDK comes with a private JVM and a handful of resources that can be used to complete the creation of the Java application.

Types of Java Applications

There are mainly four types of applications that can be created using Java programming:

1) Standalone Application

Standalone applications are also referred to as desktop or window-based applications. They are software that must be installed on each machine. Examples of standalone software include Media players, antivirus, and others. AWT and Swing are both used in Java to create standalone applications.

2) Web Application

A program that runs on the server side and generates dynamic pages is a web-based application. Servlet, JSP, Struts, Spring, Hibernate, JSF, etc. technology is used to build web-based applications in Java.

3) Enterprise Application

A program distributed by nature, like banking applications or other banking applications, is an enterprise app. It is a high-level application that offers security, load balancing, and clustering. It is a part of Java; EJB is used to create enterprise-level applications.

4) Mobile Application

A program designed specifically for mobile devices is a mobile application. Android and Java ME are the leading platforms for creating mobile apps.

Key advantages of Java

• Simple
  Java is easy to learn if you understand the concepts of OOP (Object Oriented Programming).
  
  
• Object-Oriented
  In Java, everything is considered an Object.
  
  
• Platform Independent
  This refers to Java not having to be integrated into specific machines for a particular platform. You can write the code once for one platform and then use it on various platforms without having to write it multiple times.
  
  
• Secure
  Java enables the development of virus-free systems as all the pointers work internally, and the user cannot handle pointers externally.
  
  
• Architecture-neutral
  Java compiler creates an architecture-neutral object, which makes the compiled code executable on many processors, with the presence of the Java runtime system.
  
  
• Portable 
  Java is portable, allowing us to carry the Java bytecode to any platform, and it doesn’t require any implementation.
  
  
• Robust
  It uses strong memory management and has automatic garbage collection methods etc. That’s why Java is called Robust, which means strong.
  
  
• Multithreaded
  Multithreaded because it can perform many tasks simultaneously.
  
  
• Interpreted
  Java Bytes are transformed on the fly into native machine instructions and are not stored anywhere. The development process is faster and more analytic since the link is in-situ and delicate.
  
  
• High Performance
  Java enables high performance.
  
  
• Distributed
  Java is distributed since it assists users in creating distributed applications using Java. RMI(Remote Method Invocation) and EJB(Enterprise Java Beans) are used to build distributed applications.
  
  
• Dynamic
  Java is believed to be more dynamic because Java programs can store vast amounts of runtime data that could be utilized to confirm and identify access to objects at a time.

Java Concept

The essential concepts in Java are its object-oriented programming (OOPs) features. OOP simplifies software and application development as well as maintenance by providing some concepts such as:

Object: An object in Java is like a real object with a state and behaviour. 

E.g., a pencil can be considered an object with attributes like colour, company name, etc., as well as with behaviours like writing, sketching, etc.

Class: It is a collection of objects that can be used as a blueprint to create as many objects as you want. 

E.g., different medicines belonging to a particular disease are being stored systematically under a specific section.

The Main class is known as the parent class, and the subclass as the child class.

Inheritance: Inheritance is the process where a subclass is accessible to acquire the properties and behaviours of the main or parent class.

Polymorphism: Polymorphism is the process of performing a particular work differently. 

E.g. for Two people, one takes the bus, and the other takes a bike to reach the same destination.

Abstraction: Abstraction hides the initial procedure and only shows the user relevant information.

E.g., A person knows how to start the Bike but don’t know the initial procedure (behind the scene) for beginning the Bike.

Encapsulation: Encapsulation binds all codes and keeps them in a single unit/container. E.g., A Java Class that is a collection of all objects. 

Java Features

Java has several qualities and features, including:

• The simple syntax is easy to comprehend, read, and master
• Java language is solid and robust
• Reduces the errors that occur in the C and C++ languages 
• Java comprises features like garbage collectors and exception handling 
• Because it is a portable language, Java can run on any platform
• Java is quick, secure, and can handle multitasking
• Java isn’t as fast as C or C++, but it performs better than other languages.

How to Learn Java?

Java is among the most popular programming languages, mainly because Java is naturally flexible and reliable. It is also compatible, making it the most sought-after capability to possess if you want to begin an occupation in programming.

Before you move on, think about why you want to master Java. What’s the point of taking up Java? What are you hoping to build or do with Java? Why is Java different from other languages? When you have the answer to all your questions, you’re welcome to explore various ways to understand Java.

 Here are some tips to get started:

• Explore the thousand of tutorials but select the best one suits you.
• Start with the basics of Java, such as variables, data types, conditional statements, arrays, loops, and functions.
• Make your handwritten notes as per need.
• Read books or blogs to understand the basics of Java.
• Take a step ahead and start learning advanced topics such as object-oriented programming, inheritance, abstract class, Java interface, collections, abstract classes, exceptional handling, and wrapper classes.
• Do Practice every day!!!
• Stay up-to-date with topics of Java.

Conclusion

The majority of the things that we use in our daily lives are connected to Java. Java programming language remains one of the most popular technologies used in industry, and the demand for learning for beginners is incredibly significant.

What are you waiting for? Let’s learn Java and start working towards writing your first-ever program in Java, known as “Hello World.”