rspec/rules/S3009/java/rule.adoc

It's slightly more efficient to append single characters to ``++StringBuffer++`` and ``++StringBuilder++`` instances as ``++char++``s, than as ``++String++``s. That is, it's more efficient to put a single ``++char++`` in single quotes, rather than double quotes.


== Noncompliant Code Example.

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StringBuilder sb = new StringBuilder();

sb.append("a"); // Noncompliant
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== Compliant Solution

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StringBuilder sb = new StringBuilder();

sb.append('a'); // Noncompliant
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