Error while trying to use post metod in springboot

Question

I'm learning Spring Boot rn and I'm getting errors on my way when I'm trying to use POST method.

HTTP code is 400.

That's the error:

Here is the code of my rest controller c:

package com.example.carsapi;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.awt.*;
import java.util.Optional;

@RestController
@RequestMapping("/cars")
public class CarRestController {

    private final CarService carService;

    @Autowired
    public CarRestController(CarService carService) {
        this.carService = carService;
    }

    @GetMapping
    public ResponseEntity<List> getCars(){
        return new ResponseEntity(carService.findAllCars(), HttpStatus.OK);
    }

    @GetMapping(value = "/id/{id}")
    public ResponseEntity<List> getCarById(@PathVariable Integer id){
        Optional<CarDTO> found = carService.findAllCars().stream().filter(car -> car.getCarId() == id).findFirst();
        if(found.isPresent()){
            return new ResponseEntity(found.get(), HttpStatus.OK);
        } else {
            return new ResponseEntity(HttpStatus.NOT_FOUND);
        }
    }

    @GetMapping(value = "/color/{color}")
    public ResponseEntity<List> getCarByColor(@PathVariable String color){
        Optional<CarDTO> found = carService.findAllCars().stream().filter(car -> car.getColor().equals(color)).findFirst();
        if(found.isPresent()){
            return new ResponseEntity(found.get(), HttpStatus.OK);
        } else {
            return new ResponseEntity(HttpStatus.NOT_FOUND);
        }
    }

    @PostMapping(value = "/add")
    public ResponseEntity addCar(@RequestBody CarDTO car){
        carService.findAllCars().add(car);
        return new ResponseEntity(HttpStatus.CREATED);
    }
}

And there is my JSON code which I'm using:

[ 
    {
        "carId": 3,
        "carBrand": "Audi",
        "carModel": "RS6",
        "color": "red"
    }
]

Hope you'll help me I had even tried with @RequestParam, getting all of the values like id, brand, model and color and then adding a new object with these values which I've got from the query but it still didn't work.

Please, don't do that. Don't change the question after it was correctly answered already. By doing it you make the answer obsolete. Accept the answer and create a new question instead. Thanks! — João Dias, Jan 17 '22 at 22:40
I can post once for 90 mins and I need the solution as fast as possible — Marin8, Jan 17 '22 at 22:49
Take a look at https://stackoverflow.com/questions/5755477/java-list-add-unsupportedoperationexception. — João Dias, Jan 17 '22 at 22:50
Didn't work, still 500 error. Btw I checked it closely and error is occurring while it's going to add to list. — Marin8, Jan 18 '22 at 00:04
Can you please create a new question and include there the code for `carService.findAllCars()`? — João Dias, Jan 18 '22 at 00:55

score 2 · Accepted Answer · answered Jan 17 '22 at 22:20

2

The request is an array while CarDTO is a single object. You can make the request with a body like this(notice the absence of []):

{
    "carId": 3,
    "carBrand": "Audi",
    "carModel": "RS6",
    "color": "red"
}

answered Jan 17 '22 at 22:20

Hanchen Jiang

2,514
2
9
20

now i got Http 500 code – Marin8 Jan 17 '22 at 22:22
1

So you've gone past the 400. The 500 is likely caused by something else now. – Hanchen Jiang Jan 17 '22 at 22:24
yup ik, code is the same do you know a reason mby? – Marin8 Jan 17 '22 at 22:26
What is the error message? – Hanchen Jiang Jan 17 '22 at 22:32
I've eddited a post, you can look around – Marin8 Jan 17 '22 at 22:38

Error while trying to use post metod in springboot

1 Answers1