Java Spring Boot Course Application using REST API

springrest/

This is an implementation of REST API using Java Spring Boot that can be used to perform CRUD operations to modify the contents with MySQL and Postman.

OVERVIEW

This is a Spring Boot application for managing courses. It includes the main class, SpringRestApplication, which serves as the entry point for the application. The MyController class acts as a REST controller and handles HTTP requests for CRUD operations on courses. The CourseDao interface provides access to the database using Spring Data JPA, while the CourseService interface defines operations for managing courses. The CourseServiceImpl class implements the CourseService interface and interacts with the CourseDao for database operations. The Course class represents a course entity with its properties. The application.properties file contains configuration settings for the application, including the server port and database connection details. The MySQL8Dialect class is a Hibernate dialect for MySQL version 8 databases. Lastly, the pom.xml file defines the project's dependencies and build configurations using Maven.

PRE-REQUISITES

1) Java Development Kit (JDK)

2) Integrated Development Environment (IDE)

3) Maven

4) MySQL Database

5) MySQL Connector

6) Spring Boot

HOW TO USE THE PACKET

1) Download the compressed file

2) Extract the contents

3) Import the project into your IDE (Eclipse preferred due to easy installation of Spring Boot)

4) Set up dependencies

5) Configure the database

6) Build and run the project

7) Test the functionality using Postman

SpringRestApplication.java

The SpringrestApplication class is the main class of a Spring Boot application. It is annotated with @SpringBootApplication, which combines several annotations to enable auto-configuration and component scanning. The main() method serves as the entry point of the application. It invokes SpringApplication.run() with the SpringrestApplication class and the command-line arguments (args) to start the application. This class acts as the starting point for the Spring Boot application, triggering the application's initialization and execution.

MyController.java

The MyController class is a REST controller that handles HTTP requests related to the Course entity. It is annotated with @RestController, indicating its role in processing RESTful requests. The class depends on the CourseService for handling business logic. The controller provides several endpoints, including GET /courses to retrieve all courses, GET /courses/{courseId} to fetch a specific course by ID, POST /courses to add a new course, PUT /courses to update an existing course and DELETE /courses/{courseId} to delete a course. The methods in the controller delegate the requests to the corresponding methods in the CourseService to perform the actual operations. The controller handles exceptions in the deleteCourse() method and returns appropriate HTTP response status codes. It serves as the interface between the client and the CourseService, enabling the interaction with course data through RESTful endpoints.

CourseDao.java

The CourseDao interface is a part of the Spring Data JPA framework and serves as a bridge between the application and the database for the Course entity. It inherits pre-defined methods from the JPARepository interface, allowing easy and standardized access to common database operations such as create, read, update, and delete for Course objects.

Course.java

The Course class is annotated with @Entity, indicating that it represents a persistent entity in a database. It contains fields for id, title, and description, along with corresponding getters and setters. The id field is marked with @Id, representing the primary key of the entity. The class includes a constructor for initializing the fields, including a default constructor. The toString() method provides a string representation of the Course object. This class defines the structure and properties of a course entity in the application.

CourseService.java

The CourseService interface represents a contract for managing operations related to the Course entity. It provides a set of methods to interact with course data, including fetching all courses, retrieving a specific course by ID, adding a new course, updating an existing course, and deleting a course. Implementing classes are responsible for providing concrete implementations of these methods based on the application's business logic. The interface serves as a blueprint, defining the expected behavior and functionality of the CourseService in the system.

CourseServiceImpl.java

The CourseServiceImpl class is a service implementation that handles operations related to the Course entity. It is annotated with @Service to indicate its role as a service component in the Spring framework. The class depends on the CourseDao interface, which is autowired using @Autowired for database operations. The methods in the class correspond to CRUD operations on Course objects, such as retrieving all courses, getting a specific course by ID, adding a new course, updating an existing course, and deleting a course. The implementation utilizes the methods provided by CourseDao to perform these operations. Overall, the CourseServiceImpl class acts as a bridge between the application and the database, providing functionality to manage courses efficiently.

Application.properties

The properties file contains essential configuration settings for a Java Spring Boot application. It defines the server port as 9091 (can be changed to 9090 depending on the user's system) and specifies the MySQL database connection details, including the URL, username, password, and driver class name. The Hibernate configuration includes settings for automatic schema update, showing SQL statements, and specifying the MySQL dialect. These configurations ensure that the application runs on the designated port, connects to the MySQL database, and utilizes Hibernate for ORM functionality.

MySQL8Dialect

This Java class named MySQL8Dialect is located in the org.hibernate.dialect package. It extends the MySQLDialect class and is used as a Hibernate dialect for MySQL version 8 databases. It registers additional keywords specific to MySQL 8, ensuring compatibility with Hibernate. The class defines a constructor that sets the database version to MySQL 8. This class is intended to be used with MySQL 8 databases when working with Hibernate.

pom.XML

The pom.xml file is an XML configuration file used in Maven projects. It defines the project's metadata, dependencies, and build configurations. Specifically, it represents a Spring Boot project. The file includes the project's group ID, artifact ID, and version. It lists dependencies for Spring Boot Data JPA, web development, and testing. Additionally, it includes the MySQL Connector/J dependency for MySQL database connectivity. The build section specifies the Spring Boot Maven plugin. This pom.xml file sets up the necessary configurations and dependencies for a Spring Boot project, allowing for efficient development and integration of various components.

POSTMAN

Postman is a tool used in this project to interact with the Spring Boot application's RESTful APIs. It allows you to test CRUD operations on the Course entity by sending GET, POST, PUT, and DELETE requests. With Postman, you can easily validate the functionality of the APIs, inspect the responses received from the server, and ensure the smooth execution of operations. It provides a user-friendly interface for testing, debugging, and integrating the project's APIs effectively.