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<html><head><title></title></head><body bgcolor=#ffffff> <a href="CodeConvTOC.doc.html">[Contents]</a> <a href="CodeConventions.doc5.html">[Prev]</a> <a href="CodeConventions.doc7.html">[Next]</a><hr><br> <a name="430"> </a><h2 align="center">7 - Statements</h2><a name="431"> </a><h3> 7.1 Simple Statements</h3><p><a name="434"> </a>Each line should contain at most one statement. Example:</p><blockquote><pre>argv++; // Correctargc--; // Correct argv++; argc--; // AVOID!</pre></blockquote><a name="15395"> </a><h3> 7.2 Compound Statements</h3><p><a name="15396"> </a>Compound statements are statements that contain lists of statements enclosed in braces   "<code>{  statements }</code>". See the following sections for examples.</p><ul><a name="445"> </a><li>The enclosed statements should be indented one more level than the compound statement.<a name="446"> </a><li>The opening brace should be at the end of the line that begins the compound statement; the closing brace should begin a line and be indented to the beginning of the compound statement.<a name="448"> </a><li>Braces are used around all statements, even single statements, when they are part of a control structure, such as a <code>if-else</code> or <code>for</code> statement. This makes it easier to add statements without accidentally introducing bugs due to forgetting to add braces.</ul><a name="438"> </a><h3> 7.3 return Statements</h3><p><a name="439"> </a>A <code>return</code> statement with a value should not use parentheses unless they make the return value more obvious in some way. Example:</p><blockquote><pre>return;return myDisk.size();return (size ? size : defaultSize);</pre></blockquote><a name="449"> </a><h3> 7.4 if, if-else, if else-if else Statements</h3><p><a name="450"> </a>The <code>if-else</code> class of statements should have the following form:</p><blockquote><pre>if (<em>condition</em>) { <em>statements</em>;}if (<em>condition</em>) { <em>statements</em>;} else { <em>statements</em>;}if (<em>condition</em>) { <em>statements</em>;} else if (<em>condition</em>) { <em>statements</em>;} else{ <em>statements</em>;}<a name="1734"> </a></pre></blockquote><p><B>Note:</b> <code>if</code> statements always use braces {}. Avoid the following error-prone form:</blockquote><blockquote><pre>if (<em>condition</em>) //AVOID! THIS OMITS THE BRACES {}! <em>statement</em>;</pre></blockquote><a name="454"> </a><h3> 7.5 for Statements</h3><p><a name="455"> </a>A <code>for</code> statement should have the following form:</p><blockquote><pre>for (<em>initialization</em>; <em>condition</em>; <em>update</em>) { <em>statements</em>;}</pre></blockquote><p><a name="457"> </a>An empty <code>for</code> statement (one in which all the work is done in the initialization, condition, and update clauses) should have the following form:</p><blockquote><pre>for (<em>initialization</em>; <em>condition</em>; <em>update</em>);</pre></blockquote><p><a name="458"> </a>When using the comma operator in the initialization or update clause of a <code>for</code> statement, avoid the complexity of using more than three variables. If needed, use separate statements before the <code>for</code> loop (for the initialization clause) or at the end of the loop (for the update clause).</p></pre></blockquote><a name="460"> </a><h3> 7.6 while Statements</h3><p><a name="461"> </a>A <code>while</code> statement should have the following form:</p><blockquote><pre>while (<em>condition</em>) { <em>statements</em>;}</pre></blockquote><p><a name="463"> </a>An empty <code>while</code> statement should have the following form:</p><blockquote><pre>while (<em>condition</em>);</pre></blockquote><a name="465"> </a><h3> 7.7 do-while Statements</h3><p><a name="466"> </a>A <code>do-while</code> statement should have the following form:</p><blockquote><pre>do { <em>statements</em>;} while (<em>condition</em>);</pre></blockquote><a name="468"> </a><h3> 7.8 switch Statements</h3><p><a name="469"> </a>A <code>switch</code> statement should have the following form:</p><blockquote><pre>switch (<em>condition</em>) {case ABC: <em>statements</em>; /* falls through */case DEF: <em>statements</em>; break;case XYZ: <em>statements</em>; break;default: <em>statements</em>; break;}</pre></blockquote><p><a name="15591"> </a>Every time a case falls through (doesn't include a <code>break</code> statement), add a comment where the <code>break</code> statement would normally be. This is shown in the preceding code example with the   /<code>*  falls through */</code> comment. </p><p><a name="320"> </a>Every <code>switch</code> statement should include a default case. The <code>break</code> in the default case is redundant, but it prevents a fall-through error if later another <code>case</code> is added.</p></pre></blockquote><a name="472"> </a><h3> 7.9 try-catch Statements</h3><p><a name="18717"> </a>A <code>try-catch</code> statement should have the following format:</p><blockquote><pre>try { <em>statements</em>;} catch (ExceptionClass e) { <em>statements</em>;}</pre></blockquote><p><a name="18715"> </a>A <code>try-catch</code> statement may also be followed by <code>finally</code>, which executes regardless of whether or not the <code>try</code> block has completed successfully. </p><blockquote><pre>try { <em>statements</em>;} catch (ExceptionClass e) { <em>statements</em>;} finally { <em>statements;</em>}</pre></blockquote><hr><br> <a href="CodeConvTOC.doc.html">[Contents]</a> <a href="CodeConventions.doc5.html">[Prev]</a> <a href="CodeConventions.doc7.html">[Next]</a> <hr><br><i><a href="Copyright.doc.html">Copyright</a> © 1995-1999, Sun Microsystems, Inc. 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