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<qhelp>

<overview>

<p>Conditional expressions of the form <code>(p ? e1 : e2)</code> can

yield unexpected results if <code>e1</code> and <code>e2</code> have

distinct primitive types.</p>

</overview>

<example>

<p>The following example illustrates the most confusing case, which occurs when one branch has type <code>char</code>

and the other branch does not have type <code>char</code>.</p>

<sample src="CondExprTypes.java" />

<p>This unexpected result is due to binary numeric promotion

of <code>'x'</code> from <code>char</code> to <code>int</code>.

For details on the result type of

the conditional operator, see the references.

</p>

</example>

<recommendation>

<p>When using the ternary conditional operator with numeric operands,

the second and third operand should have the same numeric type.

This avoids potentially unexpected results caused by binary numeric promotion.

</p>

</recommendation>

<references>

<li>

J. Bloch and N. Gafter, <em>Java Puzzlers: Traps, Pitfalls, and Corner Cases</em>, Puzzle 8. Addison-Wesley, 2005.

</li>

<li>

Java Language Specification:

<a href="https://docs.oracle.com/javase/specs/jls/se11/html/jls-15.html#jls-15.25">Conditional Operator ? :</a>.

</li>

</references>

</qhelp>