عملیات CRUD (ایجاد ، خواندن ، به روزرسانی ، حذف) با استفاده از Boot Spring Java با PostgreSQL-2025

spring.application.name=java-crud-postgre-sql
spring.datasource.url=jdbc:postgresql://localhost:5432/database_name
spring.datasource.username=DB user name
spring.datasource.password=DB password here
spring.datasource.driver-class-name=org.postgresql.Driver

spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect

server.port=8080

package com.example.demo.model;

import jakarta.persistence.*;

@Entity
public class Product {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String name;
    private Double price;

    // Getters and Setters
}

package com.example.demo.repository;

import com.example.demo.model.Product;
import org.springframework.data.jpa.repository.JpaRepository;

public interface ProductRepository extends JpaRepository {
}

package com.example.demo.service;

import com.example.demo.model.Product;
import com.example.demo.repository.ProductRepository;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Optional;

@Service
public class ProductService {

    private final ProductRepository repo;

    public ProductService(ProductRepository repo) {
        this.repo = repo;
    }

    public List getAll() {
        return repo.findAll();
    }

    public Product save(Product product) {
        return repo.save(product);
    }

    public Optional getById(Long id) {
        return repo.findById(id);
    }

    public void deleteById(Long id) {
        repo.deleteById(id);
    }

    public Product update(Long id, Product updatedProduct) {
        return repo.findById(id).map(product -> {
            product.setName(updatedProduct.getName());
            product.setPrice(updatedProduct.getPrice());
            return repo.save(product);
        }).orElseThrow(() -> new RuntimeException("Product not found"));
    }
}

package com.example.demo.controller;

import com.example.demo.model.Product;
import com.example.demo.service.ProductService;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/api/products")
public class ProductController {

    private final ProductService service;

    public ProductController(ProductService service) {
        this.service = service;
    }

    @GetMapping
    public List getAll() {
        return service.getAll();
    }

    @GetMapping("/{id}")
    public ResponseEntity getById(@PathVariable Long id) {
        return service.getById(id)
                .map(ResponseEntity::ok)
                .orElse(ResponseEntity.notFound().build());
    }

    @PostMapping
    public Product create(@RequestBody Product product) {
        return service.save(product);
    }

    @PutMapping("/{id}")
    public Product update(@PathVariable Long id, @RequestBody Product product) {
        return service.update(id, product);
    }

    @DeleteMapping("/{id}")
    public ResponseEntity delete(@PathVariable Long id) {
        service.deleteById(id);
        return ResponseEntity.noContent().build();
    }
}