What is Core Java?

Java is a programming language that is class-based and object-oriented. It is designed to be general-purpose and aims to have fewer implementation dependencies, and serves as a computing platform for application development. However, many new to the software industry often ask what Core Java is.

What is Core Java?

To have clarity on the core Java concepts, you must understand that core Java is a fundamental version of Java establishing the groundwork for all future Java iterations and associated technologies like CORBA and Java VM. Core Java refers to a collection of libraries rather than the programming language itself.

Advantages of Java

Here are some of the key advantages of Java are as follows:

1. It is a simple programming language that is very easy to learn and comprehend.
2. Java does not offer explicit pointers, operator overloading, etc., which even makes reading and writing Java much easier. This even makes Java a secure programming language.
3. It is an object-oriented paradigm where all in Java are objects and includes concepts like abstraction, class, etc.
4. Java’s robustness lies in its strong memory management and built-in exception handling.
5. It is platform-independent that allows code to run on different platforms with no requirement for recompilation.
6. Java excels in multi-threaded environments, allowing for the division of tasks into separate threads that can run concurrently.

Java Editions

To have a clear understanding of the core Java, it is important that you know about the different defined editions supported by Java. Here are some of those key Java editions:

1. Java SE (Java Standard Edition)

Java SE serves as a computing platform used to develop desktop or window-based applications. Core Java refers to the fundamental part of Java SE, where developers create desktop applications using basic Java concepts. JDK (Java Development Kit) is a well-known implementation of Java SE.

2. Java EE (Java Enterprise Edition)

Also referred to as Java 2 Platform or Java Enterprise Edition OR J2EE, this edition is focused on enterprise development, enabling developers to build applications for servers. Java EE is commonly used for web development.

3. Java ME (Java Micro Edition)

Java ME is the micro edition intended for developing mobile phone applications. It is specifically tailored for mobile application development. It also helps to execute Java-based applications on mobile devices having restricted memory and processing power.

Based on the above learning, it is now clear that Core Java is an integral part of Java SE, which is the main foundation for all other Java Editions.

Concepts in Core Java

Here, we will discuss some key Core Java concepts

1. Java Fundamentals

It represents the main variant of Core Java, typically used for developing regular desktop applications. It encompasses a subset of Java SE technology, incorporating both general-purpose and specific-purpose APIs, combining essential Java capabilities with a comprehensive understanding of the language.

2. OOPs Concepts

Object-Oriented Programming (OOP) is the programming paradigm that is basically based on the concepts of objects that include data and behaviour. We all know Java is an object-oriented language, and here are some of the key OOP concepts which are included in the Core Java syllabus

• Class: These are the templates that determine the structure and action of the objects. It encompasses data and functions which exist on that data.
• Object: They are basically examples of class- a real demonstration of the structure.
• Encapsulation: It refers to the gathering of data and the method which functions and works on the data included in a class.
• Inheritance: It helps the class to inherit properties and behaviour from different classes, which we also called as a superclass.
• Polymorphism: This allows objects of diverse types of classes to be regarded as the object of the superclass.
• Abstraction: It mainly addresses concealing the information on the implementation of objects and only shows the important features.

3. Overloading and Overriding

• Method Overloading: It enables a class of diverse types of parameter lists to have many methods with similar types of names.
• Method Overriding: It happens when the subclass gives a particular implementation for a method that has been determined in its superclass.

4. Inheritance with Interface and Abstract Class

In Core Java, the concepts of inheritance allow the class to have properties and methods from a superclass through the “extends” keyword. By this, you can easily reuse the code and define ordered relationships between the classes.

Further, the interface is a collection of abstract methods that demonstrates the association that applied classes must follow. Here different classes can implement different interfaces.

You can also understand that abstract classes in Java cannot be instantiated on their own. It has both abstract and concrete methods. Subclasses are required to implement the abstract methods.

5. Exception Handling

Exceptional handling, as the Core Java concept, helps software developers to manage runtime errors and unforeseen situations. It makes use of “try-catch blocks for the purpose of catching and handling exceptions. This, in turn, prevents abrupt program termination.

6. Packages

In Core Java Syllabus, packages are the Core Java concepts that allow the organisation and grouping of related classes and interfaces. Using this, you can manage the namespace and allow code maintenance and its reuse.

7. Collections

Collections in Java involves managing a group of objects that provides class and interface to keep and manipulate different objects and their groups. It is mainly the data structures, like lists, maps, sets, etc., which provide different algorithms to associate with such a collection.

8. Multithreading

Multithreading in Java allows the running of different threads simultaneously. The Core Java gives built-support for multithreading by Thread class and Runnable interface.

9. Swings

Java Swings is a Graphical User Interface in the concept of Core Java that helps to develop desktop apps with a quality graphical interface. It has a certain set of components like buttons, text fields, and labels. Such options can be customised to create interactive apps.

10. Applets

Once hailed as dynamic web content, applets are small Java programs embedded within web pages. Although their popularity has diminished due to advancements in web technologies, applets once played a significant role in providing interactive content on websites. To know more about Java Applets refer to this article Java Applets Basics.

11. Java Database Connectivity (JDBC)

JDBC, short for Java Database Connectivity, is a fundamental technology that allows Java applications to interact with databases. With JDBC, developers can perform tasks like data insertion, retrieval, and modification, making it an integral part of many Java applications involving data storage.

Difference Between Core Java and Advance Java

When we are talking about Core Java, it is imperative to focus on Core Java vs Advanced Java. Let us understand the difference between Java and Core Java from the below table.

Core Java vs Advanced Java	Core Java	Advanced Java
Definition	Covers fundamental concepts of Java	Encompasses all advanced concepts of Java
Scope	General application development	Enterprise application development
Version or Edition of Java	Java Standard Edition (J2SE)	Java Enterprise Edition (J2EE)
Topics covered	Threading, Swing, OOP, Data types, operators, exception handling, etc.	Web services, Servlets, JSP, Database connectivity, EJB, etc.
Architecture	Single-tier architecture (Standalone)	Two-tier architecture (Client-side and Server-side)
Expertise	Prerequisite for Advanced Java development	Specialised skills in areas like database, networking, etc.

This table clearly outlines the distinctions between Core Java vs. Advanced Java, emphasising their respective definitions, application scopes, topics covered, architectural approaches, and expertise requirements.