我用的是angular 9和spring boot 2。

我在angular 9中有一个服务类:

import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';
import { Book } from '../common/book';
import { BookCategory } from '../common/book-category';
import { Finalcart } from '../common/finalcart';

const httpOptions = {
  headers: new HttpHeaders({ 'Content-Type': 'application/json' })
};


@Injectable({
  providedIn: 'root'
})
export class BookService {

  private finalCart="http://localhost:8080/api/test/";

  constructor(private httpClient:HttpClient) { }


addFinalCart(finalCart:Finalcart):Observable<any>{
 return this.httpClient.post(`${this.finalCart}`+'finalCart',finalCart,httpOptions);   
}

}

在我的spring boot中，api公开为:

@CrossOrigin(origins = "*", maxAge = 3600)
@RestController
@RequestMapping("/api/test")
public class TestController {
    @PostMapping("/finalCart")
        @PreAuthorize("hasRole('USER') or hasRole('MODERATOR') or hasRole('ADMIN')")
        public ResponseEntity<?> finalCart(@RequestBody Finalcart finalCart) {
            
        Authentication auth = SecurityContextHolder.getContext().getAuthentication();
            String user = auth.getName();
            
            System.out.println(user);
           System.out.println(finalCart);
        
           UserDetailsImpl userDetails=(UserDetailsImpl)userdetailService.loadUserByUsername(user);
            User u=new User(userDetails.getId(),userDetails.getUsername(),userDetails.getPassword(),userDetails.getEmail());
         Order ord= orderRep.save(new Order(u,new Date()));
             
        Billingaddress ba= billAddressRepo.save(new Billingaddress(finalCart.getBillingAddress(),ord));
        System.out.println(ba);
         
         Shippingaddress sa=shippingAddressRepo.save(new Shippingaddress(finalCart.getShippingAddress(),ord));
         System.out.println(sa);
         
         finalCart.getCartItem().forEach(s->{
             Optional<Book> b=bookrepository.findById(Long.valueOf(s.getBookId()).longValue());
            CartItem c=cartItemRepo.save(new CartItem(s.getName(),s.getImageUrl(),s.getUnitPrice(),s.getQuantity(), b.get()));
            orderDetailRepostiory.save(new OrderDetails(c,ord));    
         });
         
                if(ord!=null) {
        return  new ResponseEntity(ord, HttpStatus.OK);
            }
            else {
        return  new ResponseEntity("BadException", HttpStatus.BAD_REQUEST);
            }
            
            
        }
    }
}

因此，当我调用api/finalcart时，我得到的错误为:

2020-07-05 19:57:08.187  WARN 17400 --- [nio-8080-exec-6] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.http.converter.HttpMessageNotReadableException: Required request body is missing: public org.springframework.http.ResponseEntity<?> in.ashwin.onlinebookstore.controller.TestController.finalCart(in.ashwin.onlinebookstore.entity.Finalcart)]

因此复制了相同的JSON数据，并试图从邮递员发送此数据，但它是工作的。

我发送JSON数据，当我从Postman发送数据时没有出现错误，但是当我尝试使用angular service类发送数据时，我得到了错误。

我的finalcart.java是:

package in.ashwin.onlinebookstore.entity;

import java.util.List;

public class Finalcart {
    
private Billingaddress  billingAddress;
private Creditcard creditCard;
private Shippingaddress shippingAddress;
private List<CartItem> cartItem;

public Billingaddress getBillingAddress() {
    return billingAddress;
}
public void setBillingAddress(Billingaddress billingAddress) {
    this.billingAddress = billingAddress;
}
public Creditcard getCreditCard() {
    return creditCard;
}
public void setCreditCard(Creditcard creditCard) {
    this.creditCard = creditCard;
}

 
@Override
public String toString() {
    return "Finalcart [billingAddress=" + billingAddress + ", creditCard=" + creditCard + ", shippingAddress="
            + shippingAddress + "]";
}
public Finalcart() {
    
}
public Shippingaddress getShippingAddress() {
    return shippingAddress;
}
public void setShippingAddress(Shippingaddress shippingAddress) {
    this.shippingAddress = shippingAddress;
}
public List<CartItem> getCartItem() {
    return cartItem;
}
public void setCartItem(List<CartItem> cartItem) {
    this.cartItem = cartItem;
}

}

Book.Component.TS。 当我单击submit按钮时，方法onSubmit（）会被触发。我正在使用JWT进行身份验证？在进行后映射时，我是否也需要传递JWT令牌？

@Component({
  selector: 'app-checkout',
  templateUrl: './checkout.component.html',
  styleUrls: ['./checkout.component.css']
})
export class CheckoutComponent implements OnInit {

  cartItems: CartItem[] = [];
  totalPrice: number = 0;
  totalQuantity: number = 0;
  checkoutFormGroup: FormGroup;
   finalCart:Finalcart;

  constructor(private formBuilder: FormBuilder,private _cartService: CartService,
    private _bookService:BookService) { }

 
  ngOnInit() {
//I have not included all codes,only the required ones.
   }
  onSubmit() {
    if (this.checkoutFormGroup.invalid) {
      return;
  }
  console.log(this.cartItems);
  console.log('Purchase the books');
      let finalCart=new Finalcart(this.checkoutFormGroup.value.billingAddress,
    this.checkoutFormGroup.value.shippingAddress, this.checkoutFormGroup.value.creditCard, this.cartItems);
    
    console.log('finalcart is',finalCart);
    this._bookService.addFinalCart(this.finalCart);
  }
}