title: Purpose of String.toLowerCase() with default locale?
body: <p>Java has two overloads each for String.toLowerCase and toUpperCase. One of the overloads takes a Locale as a parameter while the other one takes no parameters and uses the default locale (<code>Locale.getDefault()</code>).</p>
  
  <p>The parameterless variants might not work as expected because case conversion respects internationalization, and the default locale is system dependent. Most notably, the lower case i is converted to an upper case dotted İ in the Turkish locale.</p>
  
  <p><strong>What is the purpose of these methods? Do the parameterless variants have any legitimate use?</strong> Or perhaps they were just a design mistake? (Not unlike several I/O APIs that use the system default character encoding by default.)</p>