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<div align="center" class="title">JAVA程序員必讀：基礎篇(5)---類和繼承</div>
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<div align="center"><font color="#666666">編譯：ZSC/太平洋網絡學院</font></div>
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<div align="right" class="gray"><a href="mailto:tntst@pconline.com.cn">［責編:爆破手］</a></div>
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<p class="article"><b>5.2 管理繼承</b></p>
<p class="article"> 回顧前面的教程，extends子句聲明了你的類是其它類的子類。你可以為你的類指定為父類（JAVA不支持多個類支持），即使你從你的聲明中去掉extends子句，你的類也可以為父類。所以，在JAVA中的每個類都有一個或者只有一個直接的父類。</p>
<p class="article"> 如圖27所示，是一個最頂端的類，所有的類都是從這個類繼承而來的，這個Object類是定義在java.lang。
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<p class="article">（圖27）</p>
<p class="article"> 這個Object類定義和執行了在JAVA系統需要的所有類的行為。它是所有類的父類。</p>
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