Java Programming Essentials : Core Concepts and Naming Standards

Four Core Concepts

Java, as an object-oriented programming language, is structured around four fundamental concepts: Variables, Methods, Objects, and Classes. These concepts form the foundation of every Java program. Java organizes these concepts into a hierarchy, where each concept plays a crucial role in building and managing the code.

Illustration: Student Registration System

To illustrate these concepts, consider a Student Registration System:

1. Class

• A class is a blueprint for creating objects. It defines properties (variables) and behaviours (methods) that the objects will have.
• Example: The Student class serves as the template for student objects. It includes attributes like name, studentId, grade, and methods such as registerForCourse(), payFees(), and submitAssignment().

2. Object

• An object is an instance of a class. It embodies the specific values for the attributes defined by the class.
• Example: Individual students like Tom Wilson, Jim Ferdo, and Mary Json are objects created from the Student class. Each student object has unique values for attributes such as name and studentId.

3. Method

• Methods are functions defined within a class that describe the behaviors or actions that objects can perform.
• Example: The Student class includes methods like registerForCourse(), payFees(), and viewClassSchedule() which define what actions a student object can execute.

4. Variable

• Variables (also known as attributes) store the data or state related to an object.
• Example: Each student object has variables such as name, studentId, birthDate, and grade, which hold specific values for each student.

Standards for Java Class, Method, and Variable Naming Conventions

When writing Java code, adhering to proper naming conventions ensures your code is readable, maintainable, and professional. Well-structured code with consistent naming makes it easier for developers to collaborate and reduces misunderstandings in the codebase. While these conventions are not strict rules enforced by the language, they are best practices that help everyone maintain a common style. This consistency improves readability, makes debugging simpler, and encourages collaboration. In this article, we’ll cover the standard naming conventions for Java classes, methods, and variables, which are crucial for writing clean, consistent, and understandable Java programs

    camelCase

Class Naming Conventions 

• Use Nouns:

Classes represent things, so name them accordingly (ex: Student, Course).

• Start with Uppercase:

          Always capitalize the first letter of the class name.

• Follow CamelCase:

If the class name consists of multiple words, they should be written together without spaces, with each word starting with an uppercase letter (ex: StudentProfile, CourseRegistration).

 

Method Naming Conventions

• Use Verbs:

Method names should describe what they do (ex: payFees()).

• Start with a Lowercase Letter:

Begin method names with a lowercase letter.

• Use camelCase for Multi-word Names:

For methods with multiple words, start with a lowercase letter and capitalize the first letter of each subsequent word (ex: registerForCourse(), submitAssignment()).

Java

Variable Naming Conventions

• Start with a Lowercase Letter:

Begin variable names with a lowercase letter (ex:  name,grade,studentId).

• Use camelCase:

For variable names with multiple words, use camelCase, where the first word is lowercase and each subsequent word starts with an uppercase letter (ex: firstName, totalAmount).

• Be Descriptive:

Choose names that clearly describe the data stored (ex: studentName instead of name, studentId instead of id).

Simple Java Code Example Demonstrating Core Concepts