java-tutorials/patterns/dipmodular/com.baeldung.dip.daoimpleme.../com/baeldung/dip/daoimplementations/SimpleCustomerDao.java

31 lines
715 B
Java

package com.baeldung.dip.daoimplementations;
import com.baeldung.dip.daos.CustomerDao;
import com.baeldung.dip.entities.Customer;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
public class SimpleCustomerDao implements CustomerDao {
private Map<Integer, Customer> customers = new HashMap<>();
public SimpleCustomerDao() {
}
public SimpleCustomerDao(Map<Integer, Customer> customers) {
this.customers = customers;
}
@Override
public Optional<Customer> findById(int id) {
return Optional.ofNullable(customers.get(id));
}
@Override
public List<Customer> findAll() {
return new ArrayList<>(customers.values());
}
}