associations(关联) An association represents the relationship between two or more classes 关联就是类和类之间的关系。 Association is represented by a solid line that connects the two classes For instance a professor instructs students Student Professor clients hold bank accounts Client BankAccount14 Associations (关联) • An association represents the relationship between two or more classes. – 关联就是类和类之间的关系。 • Association is represented by a solid line that connects the two classes. • For instance: – a professor instructs students – clients hold bank accounts Student Professor Client BankAccount