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E-Commerce Backend — Spring Boot REST API

Last Updated : 26 May, 2026

title: E-Commerce Backend

Projects90 words12 headingsExamples included

title: E-Commerce Backend description: Spring Boot se E-Commerce REST API

Full-featured e-commerce backend with product catalog, cart, orders aur payments.

Features

Product CRUD aur Search
Category management
User registration aur login (JWT)
Shopping Cart
Order placement aur tracking
Payment integration (mock)
Admin panel endpoints

Technology Stack

Java 17
Spring Boot 3.x
Spring Data JPA
Spring Security + JWT
MySQL
Maven

API Endpoints

Auth

POST /api/auth/register — New user register POST /api/auth/login — Login, JWT token milega

Products

Code exampleWoHoTech

GET    /api/products              — Sabhi products
GET    /api/products/{id}         — Ek product
GET    /api/products/search?q=    — Search
GET    /api/products/category/{c} — Category filter
POST   /api/products              — Add product (Admin)
PUT    /api/products/{id}         — Update (Admin)
DELETE /api/products/{id}         — Delete (Admin)

Cart

Code exampleWoHoTech

GET    /api/cart                  — Cart dekho
POST   /api/cart/add              — Item add karo
PUT    /api/cart/update           — Quantity update
DELETE /api/cart/remove/{itemId}  — Item hatao
DELETE /api/cart/clear            — Cart clear karo

Orders

POST /api/orders/place — Order place karo GET /api/orders — My orders GET /api/orders/{id} — Order details PUT /api/orders/{id}/cancel — Cancel karo

Main Entity Classes

Product.java

java exampleWoHoTech

@Entity
@Table(name = "products")
public class Product {
    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false)
    private String name;

    @Column(length = 1000)
    private String description;

    private double price;
    private int stockQuantity;
    private String imageUrl;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "category_id")
    private Category category;

    private boolean isActive = true;

    @CreationTimestamp
    private LocalDateTime createdAt;
    // Getters, Setters
}

Order.java

java exampleWoHoTech

@Entity
@Table(name = "orders")
public class Order {
    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @ManyToOne
    @JoinColumn(name = "user_id")
    private User user;

    @OneToMany(mappedBy = "order", cascade = CascadeType.ALL)
    private List<OrderItem> items;

    private double totalAmount;

    @Enumerated(EnumType.STRING)
    private OrderStatus status = OrderStatus.PENDING;

    private String shippingAddress;

    @CreationTimestamp
    private LocalDateTime orderDate;
    // Getters, Setters
}

enum OrderStatus { PENDING, CONFIRMED, SHIPPED, DELIVERED, CANCELLED }

ProductController.java

java exampleWoHoTech

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

    @Autowired private ProductService productService;

    @GetMapping
    public ResponseEntity<Page<Product>> getAll(
            @RequestParam(defaultValue = "0") int page,
            @RequestParam(defaultValue = "10") int size,
            @RequestParam(defaultValue = "name") String sortBy) {
        return ResponseEntity.ok(productService.findAll(page, size, sortBy));
    }

    @GetMapping("/{id}")
    public ResponseEntity<Product> getById(@PathVariable Long id) {
        return productService.findById(id)
            .map(ResponseEntity::ok)
            .orElse(ResponseEntity.notFound().build());
    }

    @GetMapping("/search")
    public ResponseEntity<List<Product>> search(@RequestParam String q) {
        return ResponseEntity.ok(productService.search(q));
    }

    @PostMapping
    @PreAuthorize("hasRole('ADMIN')")
    public ResponseEntity<Product> create(@RequestBody @Valid Product product) {
        return ResponseEntity.status(201).body(productService.save(product));
    }

    @PutMapping("/{id}")
    @PreAuthorize("hasRole('ADMIN')")
    public ResponseEntity<Product> update(@PathVariable Long id, @RequestBody Product product) {
        return ResponseEntity.ok(productService.update(id, product));
    }

    @DeleteMapping("/{id}")
    @PreAuthorize("hasRole('ADMIN')")
    public ResponseEntity<Void> delete(@PathVariable Long id) {
        productService.delete(id);
        return ResponseEntity.noContent().build();
    }
}

application.properties

properties exampleWoHoTech

server.port=8080
spring.datasource.url=jdbc:mysql://localhost:3306/ecommerce_db
spring.datasource.username=root
spring.datasource.password=password
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=false
app.jwt.secret=mySecretKey1234567890abcdefghijklmnop
app.jwt.expiration=86400000

Exam Focus

Revise definitions, diagrams, examples, and short-answer points for E-Commerce Backend — Spring Boot REST API.

Interview Use

Prepare one clear explanation, one practical example, and one common mistake for this Java topic.

Search Terms

java, java programming, core java, java master course, java notes, master, course, projects

Continue learning this concept

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Java Topics

E-Commerce Backend — Spring Boot REST API

Last Updated : 26 May, 2026

title: E-Commerce Backend

Projects90 words12 headingsExamples included

title: E-Commerce Backend description: Spring Boot se E-Commerce REST API

Full-featured e-commerce backend with product catalog, cart, orders aur payments.

Features

Product CRUD aur Search
Category management
User registration aur login (JWT)
Shopping Cart
Order placement aur tracking
Payment integration (mock)
Admin panel endpoints

Technology Stack

Java 17
Spring Boot 3.x
Spring Data JPA
Spring Security + JWT
MySQL
Maven

API Endpoints

Auth

POST /api/auth/register — New user register POST /api/auth/login — Login, JWT token milega

Products

Code exampleWoHoTech

GET    /api/products              — Sabhi products
GET    /api/products/{id}         — Ek product
GET    /api/products/search?q=    — Search
GET    /api/products/category/{c} — Category filter
POST   /api/products              — Add product (Admin)
PUT    /api/products/{id}         — Update (Admin)
DELETE /api/products/{id}         — Delete (Admin)

Cart

Code exampleWoHoTech

GET    /api/cart                  — Cart dekho
POST   /api/cart/add              — Item add karo
PUT    /api/cart/update           — Quantity update
DELETE /api/cart/remove/{itemId}  — Item hatao
DELETE /api/cart/clear            — Cart clear karo

Orders

POST /api/orders/place — Order place karo GET /api/orders — My orders GET /api/orders/{id} — Order details PUT /api/orders/{id}/cancel — Cancel karo

Main Entity Classes

Product.java

java exampleWoHoTech

@Entity
@Table(name = "products")
public class Product {
    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false)
    private String name;

    @Column(length = 1000)
    private String description;

    private double price;
    private int stockQuantity;
    private String imageUrl;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "category_id")
    private Category category;

    private boolean isActive = true;

    @CreationTimestamp
    private LocalDateTime createdAt;
    // Getters, Setters
}

Order.java

java exampleWoHoTech

@Entity
@Table(name = "orders")
public class Order {
    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @ManyToOne
    @JoinColumn(name = "user_id")
    private User user;

    @OneToMany(mappedBy = "order", cascade = CascadeType.ALL)
    private List<OrderItem> items;

    private double totalAmount;

    @Enumerated(EnumType.STRING)
    private OrderStatus status = OrderStatus.PENDING;

    private String shippingAddress;

    @CreationTimestamp
    private LocalDateTime orderDate;
    // Getters, Setters
}

enum OrderStatus { PENDING, CONFIRMED, SHIPPED, DELIVERED, CANCELLED }

ProductController.java

java exampleWoHoTech

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

    @Autowired private ProductService productService;

    @GetMapping
    public ResponseEntity<Page<Product>> getAll(
            @RequestParam(defaultValue = "0") int page,
            @RequestParam(defaultValue = "10") int size,
            @RequestParam(defaultValue = "name") String sortBy) {
        return ResponseEntity.ok(productService.findAll(page, size, sortBy));
    }

    @GetMapping("/{id}")
    public ResponseEntity<Product> getById(@PathVariable Long id) {
        return productService.findById(id)
            .map(ResponseEntity::ok)
            .orElse(ResponseEntity.notFound().build());
    }

    @GetMapping("/search")
    public ResponseEntity<List<Product>> search(@RequestParam String q) {
        return ResponseEntity.ok(productService.search(q));
    }

    @PostMapping
    @PreAuthorize("hasRole('ADMIN')")
    public ResponseEntity<Product> create(@RequestBody @Valid Product product) {
        return ResponseEntity.status(201).body(productService.save(product));
    }

    @PutMapping("/{id}")
    @PreAuthorize("hasRole('ADMIN')")
    public ResponseEntity<Product> update(@PathVariable Long id, @RequestBody Product product) {
        return ResponseEntity.ok(productService.update(id, product));
    }

    @DeleteMapping("/{id}")
    @PreAuthorize("hasRole('ADMIN')")
    public ResponseEntity<Void> delete(@PathVariable Long id) {
        productService.delete(id);
        return ResponseEntity.noContent().build();
    }
}

application.properties

properties exampleWoHoTech

server.port=8080
spring.datasource.url=jdbc:mysql://localhost:3306/ecommerce_db
spring.datasource.username=root
spring.datasource.password=password
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=false
app.jwt.secret=mySecretKey1234567890abcdefghijklmnop
app.jwt.expiration=86400000

Exam Focus

Revise definitions, diagrams, examples, and short-answer points for E-Commerce Backend — Spring Boot REST API.

Interview Use

Prepare one clear explanation, one practical example, and one common mistake for this Java topic.

Search Terms

java, java programming, core java, java master course, java notes, master, course, projects

Continue learning this concept

PreviousChat Application NextEmployee Management System