title: Is there any technical reason not to use StandardCharsets in Java?
body: <p>As of Java 1.7, StandardCharsets are part of the standard library, but I work with a lot of legacy code which was written well before that was implemented. I have been replacing stuff with StandardCharsets whenever I run across it (primarily to make the code prettier/cleaner), but I have worries about making these changes in areas which have performance-critical sections or that I can't easily debug.</p>
  
  <p>Is there any technical reason for not using Standard Charsets? As in, are there 'gotchas' or inefficiencies that might arise from using StandardCharsets instead of Guava charsets or something like getBytes("UTF-8")? I know that "These charsets are guaranteed to be available on every implementation of the Java platform.", but I don't know if they're slower or have quirks that the older methods don't have.</p>
  
  <p>To try and keep this on-topic, assume that there's no subjective force affecting this like the preference of other developers, resistance to change, etc.</p>
  
  <p>Also, if it affects anything, UTF-8 is the encoding I really care about.</p>