source: src/main/java/com/project/beautycenter/service/impl/UsersServiceImpl.java

package com.project.beautycenter.service.impl;
import com.project.beautycenter.model.Users;
import com.project.beautycenter.model.exceptions.InvalidArgumentException;
import com.project.beautycenter.model.exceptions.InvalidUsernameException;
import com.project.beautycenter.model.exceptions.InvalidUsernameOrPasswordException;
import com.project.beautycenter.repository.UsersRepository;
import com.project.beautycenter.service.UsersService;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.stereotype.Service;

import javax.management.relation.Role;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

@Service
public class UsersServiceImpl implements UsersService {
    private final UsersRepository usersRepository;
    private final PasswordEncoder passwordEncoder;

    public UsersServiceImpl(UsersRepository usersRepository, PasswordEncoder passwordEncoder) {
        this.usersRepository = usersRepository;
        this.passwordEncoder = passwordEncoder;
    }

    @Override
    public List<Users> findAll() {
        return this.usersRepository.findAll();
    }

    @Override
    public Users findbyId(Integer id) {
        return this.usersRepository.findById(id).orElseThrow(NullPointerException::new);
    }

    @Override
    public Users create(String username, String password) {
        String encryptedpassword = this.passwordEncoder.encode(password);
        Users users = new Users(username, password);
        return this.usersRepository.save(users);
    }

    public Users create(Users user) {
        Users users = new Users(user.getUsername(), passwordEncoder.encode(user.getPassword()));
        return this.usersRepository.save(users);
    }

    @Override
    public Users login(String username, String password) {
        if (username == null || username.isEmpty() || password == null || password.isEmpty()) {
            throw new InvalidArgumentException();
        }
        return usersRepository.findByUsernameAndUpassword(username, password);
    }

}