Introduction to Java

Welcome to the world of Java.

This is the first tutorial in a series of articles where we are introducing the basic concepts of Java that a beginner needs to have a firm grip on before proceeding with the language.

The focus here is to build a solid understanding of Java’s core principles.

So let’s dive in and explore the basics that will form the foundation for more in-depth learning in the upcoming tutorial.

What is Java

Java is the most preferred programming language by software developers. It is a class-based, object-oriented programming language. It has a Write Once, Run Anywhere (WORA) feature, which means that compiled Java code can run on all platforms that support Java without the need for recompilation. Developed by James Gosling at Sun Microsystems Inc. in 1995 and later acquired by Oracle Corporation, Java celebrated its 25th anniversary on May 23, 2020.

It is known for its simplicity, robustness, and security features, making it a popular choice for enterprise-level applications.

Features of Java

As a programming language, the primary objective of Java was to make it secure.

But apart from this, there are also some other features that contribute to making it one of the most preferred programming languages.

The features of Java are also known as Java buzzwords. Some of the most prominent features of Java are explained below.

Simplicity: The syntax of Java is simple, clean, and easy to understand. Moreover, as the syntax is based on C++, it can be even simpler for aspiring developers with prior knowledge of C++. Java has removed many complicated features like explicit pointers, operated overloading, etc. There is no need to remove unreferenced objects owing to the presence of an automatic garbage collector, adding to the simplicity factor.

Object-oriented programming language: Java is an object-oriented programming language, which means we organise our software as a combination of different types of objects that encompass both data and behaviour. Hence, this methodology simplifies software development and maintenance.

Platform-independent: Languages such as C, C++, etc. are compiled into platform-specific machines. A platform is the hardware or software environment in which a program runs. So a platform can either be hardware-based or software-based.

The Java platform is a software-based platform that runs on top of other hardware-based platforms. Java code can be executed on multiple platforms, for example, Windows, Linux, Sun Solaris, Mac/OS, etc. Java code is compiled by the compiler and converted into bytecode. This bytecode is platform-independent because it can be run on multiple platforms, i.e., Write Once and Run Anywhere (WORA).

Security: It is one of the most looked-upon features of Java. Because of this feature, Java is used to develop virus-free systems. This feature can be attributed to the following factors:

• No explicit pointer
• Java Programs run inside a virtual machine sandbox
• Classloader: It is a part of the Java Runtime Environment (JRE), which is used to load the Java classes into the Java virtual machine dynamically. It adds security by separating the package for the classes of the local file system from those that are imported from network sources.
• Bytecode Verifier: It checks the code fragments for illegal code that can violate access rights to objects.
• Security Manager: It determines what resources a class can access, such as reading and writing to the local disc.

The Java language provides these securities by default. Some security can also be provided by an application developer explicitly through SSL, JAAS, cryptography, etc.

Robust: The following factors are responsible for this specific characteristic:

• Strong memory management
• Lack of pointers that avoid security problems
• Automatic garbage collection to get rid of objects not in use anymore
• Presence of exception-handling and type-checking mechanisms

Portable: It facilitates us to carry the Java bytecode to any platform without requiring any implementation.

Java Terminology

For starters, familiarity with these terms is fundamental for Java developers to navigate the development and execution lifecycle of Java applications, ensuring efficient coding, portability, and effective memory management. This knowledge enables developers to build robust and cross-platform Java applications.

• Java Development Kit (JDK): It is a software development kit used for developing Java applications. It includes tools such as the Java compiler, debugger, and other utilities required for Java programming. It also contains the JRE (Java Runtime Environment), which allows developers to run their applications during the development phase.
• Java Run-time Environment (JRE): It is a part of the Java development kit and provides the runtime environment for executing Java applications. It includes the Java Virtual Machine (JVM), class libraries, and other components needed to run Java applications but does not contain development tools like compilers and debuggers.
• Java Virtual Machine (JVM): It is an integral part of both the JDK and JRE. It is a virtualized execution environment that allows Java bytecode to be executed on different platforms without modification. The JVM interprets Java bytecode or, in some cases, uses just-in-time (JIT) compilation to convert bytecode into native machine code for improved performance.
• Bytecode in the Development Process: It is an intermediate representation of a Java program generated by the Java compiler. Instead of compiling the Java source code for a specific computer architecture, the compiler produces bytecode. This bytecode is platform-independent and can be executed by any JVM, providing the ‘Write Once, Run Anywhere’ capability.
• Garbage Collector: Garbage collection is a process in programming languages with automatic memory management. It is where the system automatically reclaims memory occupied by objects that are no longer in use or referenced by the program. The purpose of a garbage collector is to free up memory resources or prevent memory leaks. It is prevalent in languages like Java, C#, and Python.
• ClassPath: In the context of Java programming, the ClassPath is an environment variable that tells the Java Virtual Machine (JVM) where to look for user-defined classes and packages. When a Java program is executed, the JVM searches for the necessary classes and resources specified in the ClassPath. It can include directories, JAR (Java Archive) files, or ZIP files containing compiled Java classes.

Applications of Java Programming

In this section, we will discuss the top applications of Java in the real world in a detailed manner.

Desktop GUI Applications: Java can be used to design flawless desktop GUI applications. Swing, Abstract Windowing Toolkit (AWT), and JavaFX are the APIs that do the work here. Using Java can have several benefits, such as platform independence, a rich set of libraries, strong community support, robust and secure object-oriented programming, multithreading support, scalability, integration capabilities, a mature ecosystem, and cross-platform compatibility.

Mobile application development: As per a survey, it has been found that Java is the second most widely used language for designing mobile applications. The reason behind it is that Java is a cross-platform network, and the applications built using this run effectively across mobile and other small-screen devices. Apps developed using Java include Netflix, Twitter, Spotify, and many more.

Advantages of using Java for mobile app development:

• It helps to write simple code.
• Cross-platform functioning
• High compatibility with Kotlin
• High security

Web applications: When it comes to the development of dynamic web applications that interact with interfaces, Java is the perfect choice because of its ability to interact with a large number of systems. Components like JSP, web servers, Spring, and Hibernate make the web development process feasible.

Advantages of using Java for web development:

• Presence of a wide range of APIs
• Excellent IDEs and tools
• Reusability of code
• Enhanced security features

Gaming applications: The presence of a wide variety of open-source frameworks makes it an apt choice for game development. It supports Dalvik Virtual Machine and jMonkeyEngine, which provide an ace in building 2D and 3D Android games. Some popular games to be developed using it are Mission Impossible III, Minecraft, and Asphalt 6.

Artificial Intelligence: Java stands out as a top choice for AI initiatives due to its robust infrastructure integrated with intelligent software that elevates AI programming. With its remarkable attributes such as enhanced user interaction, simplified debugging, user-friendly coding, standard widget tools, and more, Java contributes to achieving excellence in the artificial intelligence workflow.

Big Data Technology: It is a software tool created to examine and extract information from intricate data structures. Extensively applied in technologies such as deep learning, machine learning, and artificial learning, Java plays a pivotal role in the realm of big data. In ETL applications like Apatar, Apache Camel, and Apache Kafka,

Java is frequently employed for extracting intricate information. Moreover, Java offers notable features such as automatic garbage collection and a stack provision system, giving it a competitive advantage over other technologies. This makes Java a prevalent choice in the field of big data technology.

Embedded Systems: This term denotes the integration of small units collaborating to execute collective functions for larger systems. Java has emerged as the optimal solution for tackling escalating software complexity. Presently, a substantial number of developers utilise Java in embedded systems.

Java offers a diverse range of libraries that simplify the lives of developers, allowing embedded applications to easily reuse them and significantly enhance productivity. Additionally, the incorporation of object-oriented programming makes the development of embedded systems more accessible, even for those with minimal experience. The combination of these Java features facilitates the management of complex systems by developers.

Cloud Applications: Cloud computing involves on-demand access to computer resources without direct user management. Java has established itself in the realm of cloud applications, presenting a cost-effective solution for IT infrastructure. It also serves as a platform for crafting cloud servers and applications.

Advantages and Disadvantages of Java

Java has been used in a large number of applications over the years. However, it has various advantages and disadvantages, as given below.

Advantages of Java

Platform independence: Java applications can be run on any device with a compatible Java Virtual Machine (JVM), improving the flexibility and reach of Java applications.

Rich set of libraries: Java provides a comprehensive standard library and various frameworks. These libraries offer pre-built modules and functions, saving time and simplifying development tasks for common coding functionalities.

Object-oriented programming: Java is based on the principles of object-oriented programming (OOP), promoting modular and reusable code. OOP concepts such as encapsulation, inheritance, and polymorphism enhance code organisation and maintainability.

Multithreading Support: Java provides built-in support for multithreading, allowing concurrent execution of multiple threads. This is essential for developing responsive and efficient applications that can perform multiple tasks simultaneously.

Integration Capabilities: Java supports seamless integration with other languages and technologies through mechanisms like the Java Native Interface (JNI) and various APIs. This enables interoperability with existing systems and the integration of Java applications with diverse technologies.

Disadvantages of Java

Slower execution speed: Java is often said to have a slower execution speed as compared to languages like C and C++. This is because the presence of the Java Virtual Machine (JVM) for the execution of the code adds an extra layer of interpretation and translation.

Memory Consumption: The requirement for the Java Runtime Environment (JRE) and automatic memory management by the garbage collector can result in higher memory consumption as compared to the languages that allow more manual memory control.

Lack of low-level access: As Java is designed to be more safe and secure, it restricts low-level access to system resources. As a result, it might restrict certain functionalities that might be crucial for system-level programming.

Limited hardware access: Java’s design philosophy opts for a 'sandbox' approach for security reasons. While this is beneficial for security, it limits direct access to hardware, making the implementation of certain low-level operations difficult.

Steep Learning Curve: For beginners, Java might have a steeper learning curve compared to some other languages. The strict syntax and object-oriented concepts can be challenging for those new to programming.

Conclusion

As you start learning Java, think of this tutorial as the first step into a series that will dig deeper into Java, explaining its details in an easy-to-understand way. Prepare for a fun journey exploring what Java can do!

Stay tuned for more helpful information, tips, and practical guidance in the next tutorials. Whether you're just starting or you've been coding for a while, these tutorials are here to make Java friendly and fun. Enjoy coding, and may your programming adventures be full of exciting discoveries and achievements!