code: private static String getProviderProperty(String key, Provider provider) {
          String prop = provider.getProperty(key);
          if (prop == null) {
              // Is there a match if we do a case-insensitive property name
              // comparison? Let's try ...
              for (Enumeration<Object> e = provider.keys();
                                  e.hasMoreElements() && prop == null; ) {
                  String matchKey = (String)e.nextElement();
                  if (key.equalsIgnoreCase(matchKey)) {
                      prop = provider.getProperty(matchKey);
                      break;
                  }
              }
          }
          return prop;
      }
docs: Returns the property (if any) mapping the key for the given provider.