java-tutorials/spark-java/src/main/java/com/baeldung/sparkjava/UserServiceMapImpl.java

package com.baeldung.sparkjava;

import java.util.Collection;
import java.util.HashMap;

public class UserServiceMapImpl  implements UserService{
    private HashMap<String, User> userMap;
    
    public UserServiceMapImpl() {
        userMap = new HashMap<>();
    }

    @Override
    public void addUser (User user) {
        userMap.put(user.getId(), user);
    }
    
    @Override
    public Collection<User> getUsers () {
        return  userMap.values();
    }
    
    @Override
    public User getUser (String id) {
        return userMap.get(id);
    }
    
    @Override
    public User editUser (User forEdit) throws UserException{
        try{
            if (forEdit.getId() == null) 
                throw new UserException("ID cannot be blank");
            
            User toEdit = userMap.get(forEdit.getId());
            
            if (toEdit == null )
                throw new UserException("User not found");
            
            if (forEdit.getEmail()!=null) {
                toEdit.setEmail(forEdit.getEmail());
            }
            if (forEdit.getFirstName()!=null) {
                toEdit.setFirstName(forEdit.getFirstName());
            }
            if (forEdit.getLastName()!=null) {
                toEdit.setLastName(forEdit.getLastName());
            }
            if (forEdit.getId()!=null) {
                toEdit.setId(forEdit.getId());
            }

            return toEdit;
        }catch (Exception ex) {
            throw new UserException(ex.getMessage());
        }
    }
    
    @Override
    public void deleteUser (String id) {
        userMap.remove(id);
    }
    
    @Override
    public boolean userExist (String id) {
        return userMap.containsKey(id);
    }

}