ArithmeticWithExtremeValues.qhelp

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<qhelp>
<overview>
<p>Assigning the maximum or minimum value for a type to a variable of that type and then using the
variable in calculations may cause overflows.</p>

</overview>
<recommendation>

<p>Before using the variable, ensure that it is reassigned a value that does not cause an overflow,
or use a wider type to do the arithmetic.</p>

</recommendation>
<example>

<p>In this example, assigning <code>Long.MAX_VALUE</code> to a variable and adding one causes
an overflow. However, casting to a <code>long</code> beforehand ensures that the arithmetic
is done in the wider type, and so does not overflow.</p>

<sample src="ArithmeticWithExtremeValues.java" />

</example>
<references>

<li>The CERT Oracle Secure Coding Standard for Java:
  <a href="https://www.securecoding.cert.org/confluence/display/java/NUM00-J.+Detect+or+prevent+integer+overflow">NUM00-J. Detect or prevent integer overflow</a>.</li>



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</references>
</qhelp>