談談軟體元件的內聚與耦合(1)

何謂內聚(Cohesion)與耦合(Coupling)呢？

再使用性——發布等價原則 (REP)

共同封閉原則 (CCP)

Class Employee {
public int calculateMonthlySalary() {...}
public int generateMonthlyHoursReport() {...}
public void saveEmployee() {...}
}

class Employee {
private String id;
public String getId() {
return id;   
　　}
}
class PaymentService {
public int calculateMonthlySalary(Employee employee) {...}
}
class WorkHoursServiceService{
public HoursReport generateMonthlyHoursReport(Employee employee) {...}
}
class EmployeeDAO {
public void saveEmployee(Employee employee) {...}
}

共同重複使用原則 (CRP)

元件內聚張力圖