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📁 java程序员必读基础篇
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<title>JAVA程序员必读：基础篇(7)---编程中的一些共同的问题 ---- |&gt;&lt;| 太平洋电脑网 -&gt; 网络学院* 开发教室</title>
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                  <div align="center" class="title">JAVA程序员必读：基础篇(7)---编程中的一些共同的问题</div>
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                  <div align="right" class="gray">&nbsp;&nbsp;&nbsp;&nbsp;</div>
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                  <div align="center"><font color="#666666">编译：ZSC/太平洋网络学院</font></div>
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                  <div align="right" class="gray"><a href="mailto:tntst@pconline.com.cn">［责编:爆破手］</a></div>
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            <p class="article"><b>问题三：程序不能工作？究竟出了什么错误？</b></p>
            <p class="article">以下是JAVA新手犯的公共错误，注意以下的各条：</p>
            <ol>
              <p> 
              <li class="article">你是否忘记在在switch语句中的每一个case语句使用break？</li>
              <p></p>
              <p> 
              <li class="article">你是否在应该使用比较运算符号==的时候使用了赋值运算符=？</li>
              <p></p>
              <p> 
              <li class="article">在循环语句中的终止条件是否正确？确保你没有过早或者过迟终止循环。也就是说，确保正确使用&lt; 
                或&lt;=或 &gt;或 &gt;= a运算符。</li>
              <p></p>
              <p> 
              <li class="article">记住数组的索引是从0开始的，因此数组的循环应该是： </li>
              <p></p>
              <p class="article"> for (int i = 0; i &lt; array.length; i++)</p>
              <p class="article"> . . .</p>
              <p> 
              <li class="article">你是否在比较浮点型数使用了==？大于号和小于号（&gt;和&lt;）运算符在对浮点数的条件逻辑中更合适。</li>
              <p></p>
              <p> 
              <li class="article">你是否对封装、继承或者其它面向对象编程和设计概念理解有问题？</li>
              <p></p>
              <p> 
              <li class="article">确保语句块圈在大括号{和}中间。下面的代码块看起来好象是对的，因为它采用缩进的编写，但是你仔细看这里缺少了{ 
                }：</li>
              <p></p>
              <p class="article"> for (int i = 0; i &lt; arrayOfInts.length; i++)</p>
              <p class="article"> arrayOfInts[i] = i;</p>
              <p class="article"> System.out.println("[i] = " + arrayOfInts[i]);</p>
              <p> 
              <li class="article">你是否正确使用条件运算符号？要确保理解&amp;&amp; 和 ||以及正确使用它们。</li>
              <p></p>
              <p> 
              <li class="article">你是否使用了否定运算符（!）？尽量不要使用它。这样会减少错误的发生。</li>
              <p></p>
              <p> 
              <li class="article">你是否使用了do-while语句。如果有，你知道do-while语句至少执行一次吗？它跟while循环语句不一样的，它可以连一次都不执行。</li>
              <p></p>
              <p> 
              <li class="article">你是否想从方法中改变参数的数值？在JAVA中的参数是由参数来传递的，它不能在方法中改变。</li>
              <p></p>
              <p> 
              <li class="article">你是否无意地增加一个分号（;）来过早终止语句？比如： </li>
              <p></p>
            </ol>
            <p class="article"> for (int i = 0; i &lt; arrayOfInts.length; i++) 
              ;</p>
            <p class="article"> arrayOfInts[i] = i</p>
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