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e21cbe82a9
Where possible update Java documentation links to Java 11. Additionally update some other links to use HTTPS.
48 lines
1.3 KiB
XML
48 lines
1.3 KiB
XML
<!DOCTYPE qhelp PUBLIC
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"-//Semmle//qhelp//EN"
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"qhelp.dtd">
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<qhelp>
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<overview>
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<p>
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A <code>switch</code> statement without a <code>default</code> case may allow execution to 'fall
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through' silently, if no cases are matched.
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</p>
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</overview>
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<recommendation>
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<p>
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In a <code>switch</code> statement that is based on a variable of a non-enumerated type, include a
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<code>default</code> case to prevent execution from falling through silently when no cases are matched.
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If the <code>default</code> case is intended to be unreachable code, it is advisable that it throws a
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<code>RuntimeException</code> to alert the user of an internal error.
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</p>
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</recommendation>
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<example>
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<p>In the following example, the <code>switch</code> statement outputs the menu choice that the user
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has made. However, if the user does not choose 1, 2, or 3, execution falls through silently.</p>
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<sample src="MissingDefaultInSwitch.java" />
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<p>In the following modified example, the <code>switch</code> statement includes a
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<code>default</code> case, to allow for the user making an invalid menu choice.</p>
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<sample src="MissingDefaultInSwitchGood.java" />
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</example>
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<references>
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<li>
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Java SE Documentation:
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<a href="https://www.oracle.com/java/technologies/javase/codeconventions-statements.html#468">7.8 switch Statements</a>.
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</li>
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</references>
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</qhelp>
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