What is Java? Java Programming Language Guide

It is a popular object-oriented programming language that is used to create a wide variety of applications, including web applications, mobile apps, and desktop software. It is a powerful and versatile language that is easy to learn, making it a great choice for beginners. With this guide, you’ll get a better understanding of Java.

What is Java?

It is an incredibly flexible and object-oriented programming language, that has left an indelible and remarkable impact on the landscape of software development. Created by James Gosling and his team at Sun Microsystems in the 1990s, Java was designed with the idea of “Write Once, Run Anywhere” (WORA). This means that Java programs can run on any device or operating system, making it highly portable and widely adopted across diverse platforms.

Key Features and Advantages

With millions of Android apps powered by Java, it has become an extremely popular language. Beyond mobile, it is also widely used to build web and enterprise applications. Its versatility across platforms makes it a great first language for beginners to learn programming fundamentals.

Object-Oriented Approach: It follows an object-oriented paradigm, which means it organizes code into objects that interact with each other. This approach promotes modular, reusable, and maintainable code, enhancing the efficiency and scalability of applications.
Platform Independence: Platform independence is one of its most significant advantages. When a Java program is compiled, it produces bytecode, which can be executed on any Java Virtual Machine (JVM). This eliminates the need to rewrite the code for different platforms, making development more efficient.
Robustness and Security: It is renowned for its robustness and safety features. Its strict type-checking and exception-handling mechanisms help identify and rectify errors during compilation. Additionally, its security features, such as the use of a security manager, ensure a secure runtime environment, protecting systems from potentially harmful code.
Rich Standard Library: It comes equipped with an extensive standard library that simplifies development tasks. The Java Standard Library includes pre-built classes and methods for common functionalities, such as input/output operations, networking, and data manipulation, reducing the need for developers to reinvent the wheel.

Why Use Java?

Java stands out in programming for its platform independence, allowing applications to run seamlessly across various systems. Its object-oriented nature fosters reusable, maintainable code, ideal for large-scale projects. A robust community and rich ecosystem provide extensive resources, enhancing developer efficiency. Additionally, Java’s emphasis on security, with features like the Java Security Manager, makes it a reliable choice for secure application development, catering to diverse programming needs in today’s digital landscape.

Is Java Free to Download?

The essential components for Java development, including the Java Development Kit (JDK) and the Java Runtime Environment (JRE), are available at no cost from Oracle’s official website. This accessibility enables users to start working on Java projects without any financial barrier.

History of Java

The history dates back to the early 1990s when a team of developers at Sun Microsystems, led by James Gosling, initiated the project known as “Oak.” The primary goal was to create a programming language that could power intelligent consumer electronic devices, like set-top boxes and home appliances. However, the team soon realized that Oak’s potential extended far beyond its initial scope.

In 1995, the World Wide Web was gaining momentum, and the internet was on the brink of a revolution. Sun Microsystems recognized the opportunities and challenges presented by this emerging technology. They rebranded Oak as “Java” and positioned it as a language that could run on any device with its “Write Once, Run Anywhere” (WORA) philosophy. This idea of platform independence was groundbreaking and set Java apart from other languages of the time.

Java quickly gained popularity due to its portability and versatility. The introduction of applets further fueled its growth, allowing developers to embed Java programs within web browsers, leading to interactive and dynamic web content.

In 1996, Sun Microsystems released Java’s first major version, Java 1.0, followed by regular updates and enhancements. Java’s adoption soared as developers recognized its potential for web development, enterprise applications, and mobile devices.

In 2009, Sun Microsystems was acquired by Oracle Corporation, which took over the development and support of Java. Despite the change in ownership, Java’s popularity continued to thrive, and it remained a dominant force in the software industry.

Over the years, Java has evolved through various versions, with each release introducing new features, improvements, and optimizations. Today, Java remains a cornerstone in the technology landscape, powering a wide array of applications, including web services, Android apps, enterprise software, and big data solutions.

What Is the Java Programming Language Used For?

With its versatile nature and wide range of features, Java is used for building all types of applications across many platforms. Here are some of the most common uses for the Java programming language:

1. Android Apps

Multiple APIs and tools allow Java developers to build fully-featured Android apps. The Android SDK is Java-based, so Java skills translate directly to Android development. Most apps from the Google Play Store are Java-powered.

2. Web Applications

Java powers many large-scale websites and web apps due to its scalability, security, and support for database integration. The Java EE platform provides APIs for building robust server-side web applications. Popular frameworks like Spring and Hibernate extend Java for web development.

3. Desktop GUI Apps

Java Swing and JavaFX APIs enable the creation of cross-platform desktop applications with graphical user interfaces. Developers can build it once and deploy it on Windows, Mac, and Linux. Complex programs like NetBeans and IntelliJ IDEA are written in Java.

4. Scientific Applications

With great performance, advanced concurrency, and libraries for technical computing, Java is commonly used for high-performance scientific and engineering apps. These include financial analysis, weather simulation, physics modeling, and more.

5. Enterprise Software

Java has many features ideal for large business systems like consistency, support for networks/databases, and automated memory management. As a result, many companies use Java for internal enterprise apps, big data processing, and backend services.

6. Distributed Systems

Java’s “write once, run anywhere” philosophy makes it great for apps spread across multiple systems. Developed with portability in mind, Java enables reliable distributed computing on machines of differing capabilities.

7. Game Development

Java’s ability to handle graphics, multimedia, and user interactions has led to its use in game development. Popular game development frameworks and libraries like LibGDX and LWJGL utilize Java to create cross-platform games.

So in summary, Java powers everything from mobile apps to web servers, to games, to scientific programs, and more. Its versatility across domains is what makes Java one of the most widely used programming languages today.

How Java Works

Java’s unique architecture is what enables it to run on any device. The key is that Java code does not compile into machine code like other languages. Instead, the Java compiler converts source code into an intermediate format called Java bytecode. This bytecode is a platform-independent instruction set that runs on the Java Virtual Machine (JVM).

The JVM is an abstract computing machine that enables high performance on any OS. It essentially acts as a layer between the bytecode and the underlying hardware. The JVM reads the bytecode, interprets each instruction, and executes the corresponding machine code for the particular operating system.

Additional components like the class loader and garbage collector run within the JVM to handle core functions. Just-in-Time (JIT) compilation improves performance by caching parts of the bytecode and converting them to native machine instructions during execution.

This architecture allows Java to provide “write once, run anywhere” portability. Developers don’t need to create different machine code binaries for each OS like with C++ or Rust. They simply compile Java code once to bytecode which then runs cross-platform through the JVM.

The JVM is available on Windows, Linux, macOS, and more. This means you can rely on your Java program running consistently on any machine. The JVM enables Java’s portability while also efficiently managing memory, security, and other lower-level details on each device.

So in summary, developers use the Java compiler to transform source code into bytecode. This bytecode then runs on any JVM, regardless of device. The JVM interprets the bytecode specific to the local machine. Bytecode is universal while the JVM handles platform-dependent execution.

Differences Between Java and JavaScript

Java and JavaScript are two distinct programming languages often used in web development, but they have different purposes, syntax, and applications. Let’s explore the key differences between Java and JavaScript:

1. Purpose and Usage

Java is distinguished by its portable “Write Once, Run Anywhere” design. Its code compiles to bytecode that operates cross-platform through the Java Virtual Machine. This portability makes it a popular choice for building server applications, desktop software, Android mobile apps, and robust enterprise systems that need to run reliably across multiple operating environments.
JavaScript, on the other hand, is a lightweight, interpreted scripting language mainly used for client-side web development. It runs within web browsers, enabling dynamic and interactive features, such as form validation, animations, and updating content without requiring page reloads.

2. Language Structure

Java utilizes a class-based, object-oriented programming paradigm. It structures software design around reusable classes and objects that encapsulate data and behavior.
JavaScript is dynamically typed, allowing variables to hold different data types at runtime without explicit declaration. It employs a prototype-based OOP model.

3. Syntax

Java syntax is similar to languages like C++ and C#. It requires the use of semicolons at the end of each statement, and code blocks are enclosed within curly braces.
JavaScript has a more relaxed syntax compared to Java. It allows optional semicolons and uses curly braces for code blocks similar to Java.

4. Concurrency

Java provides built-in support for multithreading, allowing developers to create concurrent applications that can execute multiple tasks simultaneously.
JavaScript, typically single-threaded, sequentially executes operations. Nevertheless, the introduction of Web Workers enables JavaScript to employ multiple threads for specific tasks, enhancing performance in select situations.

5. Typing and Exception Handling

Java’s strict typing enforces explicit type declarations and rigorous type-checking at compile-time, reducing the likelihood of runtime errors. It uses try-catch blocks for exception handling.
JavaScript is loosely typed, which means variables can change types during execution. It relies on try-catch statements for exception handling, but it has fewer built-in exception types compared to Java.

Why ZEGOCLOUD SDK for Java?

ZEGOCLOUD SDK for Java allows developers to integrate real-time audio calling, video calling, app chat, and live streaming features into their Java applications with ease. It is a highly optimized SDK provided by ZEGOCLOUD that greatly simplifies building the signaling and transmission infrastructure for streaming media.

With just a few lines of code, Java developers can enable audio/video communication in their apps using the ZEGOCLOUD UIKits. Features like multi-party conferencing, screen sharing, beauty filters, and more are provided out of the box. The SDK uses WebRTC technology and is optimized for high-quality, low-latency video streaming. Developers simply need to implement a few key callbacks and trigger methods to have a fully functional signaling channel.

Overall, the ZEGOCLOUD SDK makes adding powerful real-time communication capabilities to Java backends, Android apps, or any other Java program incredibly simple. Media streaming that previously required extensive development can now be achieved through a simple, well-documented API.

Conclusion

With the ability to build all kinds of applications, Java is both a powerful and flexible programming language. Its approachability makes it an ideal first language for newcomers to learn, with abundant resources available online.

After grasping the fundamentals covered here, new developers can immediately practice by coding real-time audio/video apps with the ZEGOCLOUD SDK. This hands-on experience will reinforce Java skills while creating compelling programs. Sign up now to access the SDK and start actively building out your abilities through interactive practice.