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    <p>When you enter a token which is not a number, calling nextInt does not move the scanner beyond the token. As a result, it's just reading the same token over and over.</p> <p>Here's the documentation for nextInt: <a href="http://download.oracle.com/javase/6/docs/api/java/util/Scanner.html#nextInt%28%29" rel="nofollow">http://download.oracle.com/javase/6/docs/api/java/util/Scanner.html#nextInt%28%29</a> (although the relevant behavior is actually described in the version which takes an argument, here: <a href="http://download.oracle.com/javase/6/docs/api/java/util/Scanner.html#nextInt%28int%29" rel="nofollow">http://download.oracle.com/javase/6/docs/api/java/util/Scanner.html#nextInt%28int%29</a> )</p> <p>So, to give you a quick example, let's assume that the input string is <code>"1 2 Foo"</code>. I will add an X to show where the Scanner is currently positioned. It starts out <code>"X1 2 Foo"</code>. Then the first call to <code>input.nextInt()</code> happens. It returns 1 and now we're at <code>"1 X2 Foo"</code>. Then the second call to <code>input.nextInt()</code> happens. It returns 2 and now we're at <code>"1 2 XFoo"</code>. Then the third call to <code>input.nextInt()</code> happens. It doesn't return, but rather throws an InputMismatchException and it also doesn't advance the Scanner. So we're still at <code>"1 2 XFoo"</code>. So when we call it a fourth or fifth time, the same thing happens.</p> <p>To solve this problem, an <code>input.next()</code> call will consume the next token, whatever it is. After this call, in our example, we would be at <code>"1 2 FooX"</code>.</p> <p>Note, however, that the call to <code>input.next()</code> can also still throw exceptions. Specifically, it can throw IllegalStateException if the Scanner is closed (which shouldn't happen in your code) or NoSuchElementException if the Scanner has reached the end of input (which won't happen if you're reading in from the keyboard, as I assume that you are). But just to be safe, you should either catch those errors and break out of the loop or not catch them and instead declare them as thrown by your method.</p>
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    1. POEndless while loop problem with try/catch
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    1. USKeith Irwin
    1. USKeith Irwin
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POEndless while loop problem with try/catch
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    1. This table or related slice is empty.
    1. VO
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      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
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      1. This table or related slice is empty.
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    3. VO
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    1. COThanks a-lot. One follow-up Q, what do you mean by a Scanner being closed?
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      1. USAdam
    2. CO@Adam: The class Scanner has a close() method which can be used to close the Scanner so that you can't read from it any more. This method is handy because a Scanner can be opened on a number of different input sources (files, pipes, etc.). When it's called, it will also automatically close its input source. However, if you were to call input.close() and then call input.nextInt() or input.hasNext() it would throw an IllegalStateException. This will only happen if input.close() has been called. It will not happen just because the end of input is reached.
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      1. USKeith Irwin
 

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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

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