Error: The blank final field customerRepository may not have been initialized

[martin codey]

Got error The blank final field customerRepository may not have been   initialized

@Controller
public class navbarController {

	private final CustomerRepository customerRepository;

	}

Full code:

package com.example.navbar.controller;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import com.example.navbar.customer.*;
import com.example.navbar.repositories.CustomerRepository;



@Controller
public class navbarController {

	private final CustomerRepository customerRepository;

	@Autowired
	public CustomerController(CustomerRepository customerRepository) {
		this.customerRepository = customerRepository;
	}

	@GetMapping("/Index")
	public String greeting() {
		return "Index";


	}
	@GetMapping("/About")
	public String method() {
		return "About"; //extension depends on view resolver.
	}
	@GetMapping("/Contact")
	public String contactmethod() {
		return "Contact"; //extension depends on view resolver.
	}
	@GetMapping("/new")
	public String showSignUpForm(Customer customer) {
		return "add-customer";
	}


	@GetMapping("/edit/{id}")
	public String showUpdateForm(@PathVariable("id") long id, Model model) {
		Customer customer = customerRepository.findById(id).orElseThrow(() -> new IllegalArgumentException("Invalid customer Id:" + id));
		model.addAttribute("customer", customer);
		return "update-customer";
	}

	@GetMapping("/delete/{id}")
	public String deleteUser(@PathVariable("id") long id, Model model) {
		Customer customer = customerRepository.findById(id).orElseThrow(() -> new IllegalArgumentException("Invalid customer Id:" + id));
		customerRepository.delete(customer);
		model.addAttribute("customers", customerRepository.findAll());
		return "index";
	}

	@PostMapping("/addcustomer")
	public String addUser(@Valid Customer customer, BindingResult result, Model model) {
		if (result.hasErrors()) {
			return "add-customer";
		}

		customerRepository.save(customer);
		model.addAttribute("customers", customerRepository.findAll());

		return "index";
	}

	@PostMapping("/update/{id}")
	public String updateUser(@PathVariable("id") long id, @ModelAttribute Customer customer , BindingResult result, Model model) {
		Customer customerToUpdate = customerRepository.findById(id).get();
		System.out.println("Found customer " + id);
		String newemail = customer.getEmail();
		String newName = customer.getName();
		String newSurname = customer.getSurname();
		String newGender = customer.getGender();
		Double newSsn = customer.getSsn();
		String newCityOfResidence = customer.getCityOfResidence();
		String newCountryOfResidence = customer.getCountryOfResidence();
		customerToUpdate.setEmail(newemail);
		customerToUpdate.setName(newName);
		customerToUpdate.setSurname(newSurname);
		customerToUpdate.setGender(newGender);
		customerToUpdate.setSsn(newSsn);
		customerToUpdate.setCityOfResidence(newCityOfResidence);
		customerToUpdate.setCountryOfResidence(newCountryOfResidence);



		customerRepository.save(customerToUpdate);

		model.addAttribute("customers", customerRepository.findAll());
		System.out.println("New email" +customerRepository.findById(1L).get().getEmail());
		return "index";
	}


}

Uploaded it on github to make it easier for you to see the problem:
Github

[Campbell Ritchie]

A final field must be definitely assigned (once only) by the time the constructor completes. Since the constructor in that class doesn't assign to that field, the class won't compile. What you wrote in line 25 is a method, not a constructor, because its name isn't the same as the name of the class.
By the way: always start ClassNames With CapitalLetters.

[Junilu Lacar]

It's not even a method since there is no return type.

[Campbell Ritchie]

It is a method, but it is ill‑formed because of its lack of return type; that will produce another compiler error.

[Junilu Lacar]

If you're going to use that logic then it could be argued that it is a constructor, it just has an ill-formed name.

It's NOT a constructor because it doesn't have the same name as the class.
It's NOT a method because it doesn't have a declared return type.

The intent was clearly to make a constructor, not a method.

[Campbell Ritchie]

Junilu Lacar wrote:. . . The intent was clearly to make a constructor . . .

All right then. I agree about the intent. But the compiler won't see that; it will see a method with missing return type.

[Junilu Lacar]

You're right about which way the compiler would lean and it makes sense to do it that way.

[martin codey]

Campbell Ritchie wrote:

Junilu Lacar wrote:. . . The intent was clearly to make a constructor . . .

All right then. I agree about the intent. But the compiler won't see that; it will see a method with missing return type.

I understand that it might  be a illformed constructor and I quite honest don't completely understand everything I do. But if you look at my other git repository it worked completely fine. Github second repository

[Campbell Ritchie]

The name of the class in line 20 (It should have started N not n) and the name of what you intended to be a constructor in line 25 are different. A constructor must have exactly the same name as the class and no return type. You can get serious errors if you mistakenly mark a constructor void because the javac tool won't issue any errors or warnings.

martin codey wrote:. . . don't completely understand everything I do.

In which case you should ask for explanations until you do understand what you are doing.

But if you look at my other git repository it worked completely fine. . . .

In which case, please let git or a diff program find the differences.