| is A | has A |
|
Red is A Color: class Red extends Color{} class Blue extends Color{} class Yellow exrends Color{} |
She has A friend： class She{ private Person friend; } |
|
继承关系 （分为： 接口继承——扩展父类类型或功能 略 实现继承——实现公共代码的重用 class Red extends Color{
public void sayHello(){
System.out.print("大家好,");
}
}
class Red extends Color{
@OverWrite
public void sayHello(){
super.sayHello();
System.out.println("我叫red!");
}
}
class Blue extends Color{
@OverWrite
public void sayHello(){
super.sayHello();
System.out.println("我叫blue!");
}
}
|
从属关系 |