Explanation/Reference:
Explanation:
C:The methods related directly to the entity Customer is moved to a new class.
D: Example (here Customer is the main entity):
public class Customer {
private final String id;
private String contactName;
private String phone;
public void setId(String id) { this.id = id; }
102
public String getId() { return this.id; }
public void setContactName(String cn) { this.contactName = cn;} public String getContactName() { return
this.contactName; } public void setPhone(String phone) { this.phone = phone; } public String getPhone()
{ return this.phone; }
}
public interface CustomerDAO {
public void addCustomer(Customer c) throws DataAccessException; public Customer getCustomer(String
id) throws DataAccessException; public List getCustomers() throws DataAccessException; public void
removeCustomer(String id) throws DataAccessException; public void modifyCustomer(Customer c) throws
DataAccessException; }
Note: DAO Design Pattern
*Abstracts and encapsulates all access to a data source *Manages the connection to the data source to
obtain and store data *Makes the code independent of the data sources and data vendors (e.g. plain-text,
xml, LDAP,
MySQL, Oracle, DB2)