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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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<p class="article"><b><span class="article">5.1.6 </span></b><span class="article"><b>控制對類成員的訪問</b></span><b>
</b></p>
<p> <span class="article"><b>（4）Package</b></span></p>
<p class="article"> 如果你不顯性設置成員訪問其它級別的成員的時候，使用package訪問級。這個訪問級允許在相同包中的類訪問成員。訪問的級別是假設在相同包中的類是互相信任的朋友。比如
，以下修改過的Alpha類聲明了一個單一包訪問的成員變量和方法。Alpha處在Greek包中： </p>
<p class="article">package Greek;</p>
<p class="article">class Alpha {</p>
<p class="article"> int iampackage;</p>
<p class="article"> void packageMethod() {</p>
<p class="article"> System.out.println("packageMethod");</p>
<p class="article"> }</p>
<p class="article">}</p>
<p class="article"> 這個Alpha類同時可以訪問iampackage和packageMethod。另外，所有定義在和Alpha相同的類也可以訪問iampackage和packageMethod。假如Alpha和Beta都是定義為Greek包的一部分：
</p>
<p class="article">package Greek;</p>
<p class="article">class Beta {</p>
<p class="article"> void accessMethod() {</p>
<p class="article"> Alpha a = new Alpha();</p>
<p class="article"> a.iampackage = 10; // 合法</p>
<p class="article"> a.packageMethod(); // 合法</p>
<p class="article"> }</p>
<p class="article">}</p>
<p class="article"> 如上所述，Beta可以合法訪問iampackage和packageMethod。</p>
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