Bắt Đầu với Spring Boot: Dự Án Đầu Tiên

# Cài đặt Homebrew nếu chưa có
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
 
# Cài đặt Java 21 (LTS)
brew install openjdk@21
 
# Thêm vào PATH
echo 'export PATH="/opt/homebrew/opt/openjdk@21/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc
 
# Kiểm tra cài đặt
java -version

# Cài đặt Chocolatey (chạy PowerShell as Administrator)
Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))
 
# Cài đặt Java 21
choco install temurin21
 
# Kiểm tra cài đặt
java -version

java -version

# Cập nhật package index
sudo apt update
 
# Cài đặt Java 21
sudo apt install openjdk-21-jdk -y
 
# Kiểm tra cài đặt
java -version
 
# Kiểm tra JAVA_HOME (nên được set tự động)
echo $JAVA_HOME

# Cài đặt Java 21
sudo dnf install java-21-openjdk-devel -y
 
# Kiểm tra cài đặt
java -version

# Kiểm tra phiên bản Java
java -version
 
# Kết quả mong đợi (số phiên bản có thể khác):
# openjdk version "21.0.1" 2023-10-17 LTS
# OpenJDK Runtime Environment Temurin-21.0.1+12 (build 21.0.1+12-LTS)
# OpenJDK 64-Bit Server VM Temurin-21.0.1+12 (build 21.0.1+12-LTS, mixed mode)
 
# Kiểm tra Java compiler
javac -version
 
# Kiểm tra JAVA_HOME
echo $JAVA_HOME  # macOS/Linux
echo %JAVA_HOME% # Windows

# macOS (dùng Homebrew)
brew install --cask intellij-idea-ce  # Community Edition (Miễn phí)
 
# Windows (dùng Chocolatey)
choco install intellijidea-community

# macOS
brew install --cask visual-studio-code
 
# Windows
choco install vscode

brew install maven
mvn -version

choco install maven
mvn -version

sudo apt install maven -y
mvn -version

# macOS
brew install gradle
 
# Windows
choco install gradle
 
# Linux
sudo apt install gradle -y

unzip demo.zip
cd demo

# Cài đặt Spring Boot CLI (macOS)
brew tap spring-io/tap
brew install spring-boot
 
# Tạo dự án
spring init --dependencies=web,devtools --build=maven --java-version=21 demo
 
cd demo

mvn archetype:generate \
  -DgroupId=com.example \
  -DartifactId=demo \
  -DarchetypeArtifactId=maven-archetype-quickstart \
  -DinteractiveMode=false
 
cd demo

demo/
├── src/
│   ├── main/
│   │   ├── java/
│   │   │   └── com/
│   │   │       └── example/
│   │   │           └── demo/
│   │   │               └── DemoApplication.java
│   │   └── resources/
│   │       ├── application.properties
│   │       ├── static/          # File tĩnh (CSS, JS, images)
│   │       └── templates/       # HTML templates (Thymeleaf)
│   └── test/
│       └── java/
│           └── com/
│               └── example/
│                   └── demo/
│                       └── DemoApplicationTests.java
├── target/                      # Compiled classes (tự động tạo)
├── pom.xml                      # Cấu hình Maven
├── mvnw                         # Maven wrapper (Unix)
├── mvnw.cmd                     # Maven wrapper (Windows)
└── .gitignore

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
         https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
 
    <!-- Parent POM cung cấp dependency management -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.2.2</version>
        <relativePath/>
    </parent>
 
    <!-- Thông tin dự án -->
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
 
    <!-- Phiên bản Java -->
    <properties>
        <java.version>21</java.version>
    </properties>
 
    <!-- Dependencies -->
    <dependencies>
        <!-- Spring Web (REST APIs, MVC) -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
 
        <!-- DevTools (auto-reload khi development) -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
 
        <!-- Testing -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
 
    <!-- Cấu hình build -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

package com.example.demo;
 
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
 
@SpringBootApplication  // Kết hợp @Configuration, @EnableAutoConfiguration, @ComponentScan
public class DemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

# Cấu hình server
server.port=8080
 
# Tên ứng dụng
spring.application.name=demo
 
# Logging level
logging.level.root=INFO
logging.level.com.example.demo=DEBUG

package com.example.demo.model;
 
public class Book {
    private Long id;
    private String title;
    private String author;
    private Integer year;
 
    // Constructors
    public Book() {}
 
    public Book(Long id, String title, String author, Integer year) {
        this.id = id;
        this.title = title;
        this.author = author;
        this.year = year;
    }
 
    // Getters và Setters
    public Long getId() {
        return id;
    }
 
    public void setId(Long id) {
        this.id = id;
    }
 
    public String getTitle() {
        return title;
    }
 
    public void setTitle(String title) {
        this.title = title;
    }
 
    public String getAuthor() {
        return author;
    }
 
    public void setAuthor(String author) {
        this.author = author;
    }
 
    public Integer getYear() {
        return year;
    }
 
    public void setYear(Integer year) {
        this.year = year;
    }
}

package com.example.demo.model;
 
import lombok.Data;
import lombok.AllArgsConstructor;
import lombok.NoArgsConstructor;
 
@Data                    // Tự động tạo getters, setters, toString, equals, hashCode
@NoArgsConstructor       // Constructor không tham số
@AllArgsConstructor      // Constructor với tất cả tham số
public class Book {
    private Long id;
    private String title;
    private String author;
    private Integer year;
}

package com.example.demo.controller;
 
import com.example.demo.model.Book;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
 
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
 
@RestController                    // Kết hợp @Controller và @ResponseBody
@RequestMapping("/api/books")      // Base URL cho tất cả endpoints
public class BookController {
 
    // Lưu trữ trong bộ nhớ (thay bằng database trong production)
    private List<Book> books = new ArrayList<>();
    private Long nextId = 1L;
 
    // Khởi tạo với dữ liệu mẫu
    public BookController() {
        books.add(new Book(nextId++, "Clean Code", "Robert C. Martin", 2008));
        books.add(new Book(nextId++, "Effective Java", "Joshua Bloch", 2018));
    }
 
    // GET /api/books - Lấy tất cả sách
    @GetMapping
    public List<Book> getAllBooks() {
        return books;
    }
 
    // GET /api/books/{id} - Lấy sách theo ID
    @GetMapping("/{id}")
    public ResponseEntity<Book> getBookById(@PathVariable Long id) {
        Optional<Book> book = books.stream()
            .filter(b -> b.getId().equals(id))
            .findFirst();
 
        return book.map(ResponseEntity::ok)
                   .orElse(ResponseEntity.notFound().build());
    }
 
    // POST /api/books - Tạo sách mới
    @PostMapping
    public ResponseEntity<Book> createBook(@RequestBody Book book) {
        book.setId(nextId++);
        books.add(book);
        return ResponseEntity.status(HttpStatus.CREATED).body(book);
    }
 
    // PUT /api/books/{id} - Cập nhật sách
    @PutMapping("/{id}")
    public ResponseEntity<Book> updateBook(@PathVariable Long id, @RequestBody Book updatedBook) {
        Optional<Book> existingBook = books.stream()
            .filter(b -> b.getId().equals(id))
            .findFirst();
 
        if (existingBook.isPresent()) {
            Book book = existingBook.get();
            book.setTitle(updatedBook.getTitle());
            book.setAuthor(updatedBook.getAuthor());
            book.setYear(updatedBook.getYear());
            return ResponseEntity.ok(book);
        }
 
        return ResponseEntity.notFound().build();
    }
 
    // DELETE /api/books/{id} - Xóa sách
    @DeleteMapping("/{id}")
    public ResponseEntity<Void> deleteBook(@PathVariable Long id) {
        boolean removed = books.removeIf(b -> b.getId().equals(id));
 
        if (removed) {
            return ResponseEntity.noContent().build();
        }
 
        return ResponseEntity.notFound().build();
    }
}

package com.example.demo.controller;
 
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
 
import java.util.HashMap;
import java.util.Map;
 
@RestController
public class HomeController {
 
    @GetMapping("/")
    public Map<String, String> home() {
        Map<String, String> response = new HashMap<>();
        response.put("message", "Chào mừng đến với Spring Boot API!");
        response.put("version", "1.0.0");
        response.put("docs", "http://localhost:8080/api/books");
        return response;
    }
}

# Clean và compile
./mvnw clean compile
 
# Chạy ứng dụng
./mvnw spring-boot:run

mvnw.cmd spring-boot:run

# Build JAR
./mvnw clean package
 
# Chạy JAR
java -jar target/demo-0.0.1-SNAPSHOT.jar

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.2.2)
 
2024-01-24T10:30:00.123  INFO 12345 --- [main] c.e.demo.DemoApplication: Starting DemoApplication
2024-01-24T10:30:01.456  INFO 12345 --- [main] o.s.b.w.embedded.tomcat.TomcatWebServer: Tomcat started on port(s): 8080 (http)
2024-01-24T10:30:01.789  INFO 12345 --- [main] c.e.demo.DemoApplication: Started DemoApplication in 2.1 seconds

# Lấy welcome message
curl http://localhost:8080/
 
# Lấy tất cả sách
curl http://localhost:8080/api/books
 
# Lấy sách theo ID
curl http://localhost:8080/api/books/1
 
# Tạo sách mới
curl -X POST http://localhost:8080/api/books \
  -H "Content-Type: application/json" \
  -d '{"title":"Spring in Action","author":"Craig Walls","year":2022}'
 
# Cập nhật sách
curl -X PUT http://localhost:8080/api/books/1 \
  -H "Content-Type: application/json" \
  -d '{"title":"Clean Code (Updated)","author":"Robert C. Martin","year":2008}'
 
# Xóa sách
curl -X DELETE http://localhost:8080/api/books/1

com.example.demo/
├── controller/      # REST endpoints
├── service/         # Business logic
├── repository/      # Truy cập dữ liệu
├── model/           # Domain entities
├── dto/             # Data transfer objects
├── config/          # Configuration classes
└── exception/       # Custom exceptions

package com.example.demo.service;
 
import com.example.demo.model.Book;
import org.springframework.stereotype.Service;
 
import java.util.List;
import java.util.Optional;
 
@Service
public class BookService {
    // Business logic ở đây
    public List<Book> findAll() { /* ... */ }
    public Optional<Book> findById(Long id) { /* ... */ }
    public Book save(Book book) { /* ... */ }
    public void deleteById(Long id) { /* ... */ }
}

package com.example.demo.dto;
 
public class BookDTO {
    private Long id;
    private String title;
    private String author;
    // Chỉ những field bạn muốn expose ra API
}

import jakarta.validation.constraints.NotBlank;
import jakarta.validation.constraints.Min;
 
public class Book {
    @NotBlank(message = "Title không được để trống")
    private String title;
 
    @NotBlank(message = "Author không được để trống")
    private String author;
 
    @Min(value = 1000, message = "Year phải lớn hơn hoặc bằng 1000")
    private Integer year;
}

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-validation</artifactId>
</dependency>

@PostMapping
public ResponseEntity<Book> createBook(@Valid @RequestBody Book book) {
    // ...
}

package com.example.demo.exception;
 
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
 
@RestControllerAdvice
public class GlobalExceptionHandler {
 
    @ExceptionHandler(BookNotFoundException.class)
    public ResponseEntity<ErrorResponse> handleBookNotFound(BookNotFoundException ex) {
        ErrorResponse error = new ErrorResponse(
            HttpStatus.NOT_FOUND.value(),
            ex.getMessage()
        );
        return ResponseEntity.status(HttpStatus.NOT_FOUND).body(error);
    }
}

server:
  port: 8080
 
spring:
  application:
    name: demo
 
logging:
  level:
    root: INFO
    com.example.demo: DEBUG

<dependency>
    <groupId>org.springdoc</groupId>
    <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
    <version>2.3.0</version>
</dependency>

# Tìm process đang dùng port 8080 (macOS/Linux)
lsof -i :8080
 
# Kill process
kill -9 <PID>
 
# Hoặc đổi port trong application.properties
server.port=8081

# macOS/Linux - Thêm vào ~/.zshrc hoặc ~/.bashrc
export JAVA_HOME=$(/usr/libexec/java_home -v 21)
 
# Windows - Set biến môi trường
setx JAVA_HOME "C:\Program Files\Java\jdk-21"

# Xóa Maven cache
./mvnw dependency:purge-local-repository
 
# Clean rebuild
./mvnw clean install -U