FooJiaYin/springboot-example

Example Spring Boot Application

Environment Setup

Reference:

Develop your Spring Boot application with Visual Studio Code

Prerequisites

1. Java

   $ java -version
   java version "1.8.0_271"
   Java(TM) SE Runtime Environment (build 1.8.0_271-b09)
   Java HotSpot(TM) 64-Bit Server VM (build 25.271-b09, mixed mode)

2. Maven

   choco install maven

3. Visual Studio Code

Extensions

1. Language Support for Java(TM) by Red Hat

   Need couple of minutes to install, please wait patiently.

2. Debugger for Java

3. Spring Boot Tools

4. Spring Boot Dashboard

5. Spring Initializr Java Support (to add dependencies)

Errors

• Gradle error → Delete folder C:\…\.gradle\wrapper\dists\gradle-7.5.1-bin

  Could not install Gradle distribution from 'https://services.gradle.org/distributions/gradle-7.5.1-bin.zip'  
  Timeout of 120000 reached waiting for exclusive access to file "C:\…\.gradle\wrapper\dists\gradle-7.5.1-bin"

• Install failure for 3 & 4 → Download VSIX from Marketplace and install via VSIX

Project Setup

Initialize Spring Boot Project

1. Go to Spring Initializr
   • Configuration (Example): Gradle, Java, 2.7.5 (latest stable), Jar, Java 17
2. Add dependencies
   • Spring Web
   • Spring Data JPA
   • MySQL Driver
   • Lombok
3. Generate and Download .zip
4. Open with VS Code

Run

• Use Run and Debug to Debug the application
• After making some changes, click restart to see the changes

Add API for root "/"

Add @RestController and API for "/"

@RestController
@SpringBootApplication
public class DemoApplication {
	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}
	@RequestMapping(value="/", method=RequestMethod.GET)
	public String helloWorld() {
		return "Hello World";
	}	
}

Database Setup

Extensions

• JPA
• hibernate-validator (for JPA)
• Lombok: Reduce getter & setter boilerplate code with @Getter @Setter
  • Java - 五分鐘學會 Lombok 用法

Setup Database MySQL

• Prerequisite: Have SQL installed.
  • For example, with XAMPP.

# Log in to mysql
mysql -u root -p

# Creates the new database
mysql> create database springboot_db;

# Creates the user
mysql> create user 'springuser'@'%' identified by 'ThePassword';

# Gives all privileges to the new user on the newly created database
mysql> grant all on springboot_db.* to 'springuser'@'%';

Connect Springboot with Database

Add [application.properties](http://application.properties) or application.yaml to src/main/resources

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://${MYSQL_HOST:localhost}:3306/springboot_db
spring.datasource.username=springuser
spring.datasource.password=password
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
#spring.jpa.show-sql: true