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Fix issue #596: 第八章和第九章图片错位 #600

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Merged
merged 1 commit into from
Sep 28, 2020
Merged

Fix issue #596: 第八章和第九章图片错位 #600

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2 changes: 1 addition & 1 deletion docs/book/08-Reuse.md
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Expand Up @@ -869,7 +869,7 @@ public class Wind extends Instrument {

该术语是基于传统的类继承图：图最上面是根，然后向下铺展。（当然你可以以任意方式画你认为有帮助的类图。）于是，**Wind.java** 的类图是：

![Wind 类图](../images/1561774164644.png)
![Wind 类图](../images/1562204648023.png)

继承图中派生类转型为基类是向上的，所以通常称作*向上转型*。因为是从一个更具体的类转化为一个更一般的类，所以向上转型永远是安全的。也就是说，派生类是基类的一个超集。它可能比基类包含更多的方法，但它必须至少具有与基类一样的方法。在向上转型期间，类接口只可能失去方法，不会增加方法。这就是为什么编译器在没有任何明确转型或其他特殊标记的情况下，仍然允许向上转型的原因。

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2 changes: 1 addition & 1 deletion docs/book/09-Polymorphism.md
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Expand Up @@ -184,7 +184,7 @@ Java 中除了 **static** 和 **final** 方法（**private** 方法也是隐式

形状的例子中，有一个基类称为 **Shape** ，多个不同的派生类型分别是：**Circle**，**Square**，**Triangle** 等等。这个例子之所以好用，是因为我们可以直接说“圆(Circle)是一种形状(Shape)”，这很容易理解。继承图展示了它们之间的关系：

![形状继承图](../images/1562204648023.png)
![形状继承图](../images/1561774164644.png)

向上转型就像下面这么简单：

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