code: public static StringBuilder leftShift(StringBuilder self, Object value) {
          if (value instanceof CharSequence)
              return self.append((CharSequence)value);
          else
              return self.append(value);
      }
docs: Overloads the left shift operator to provide an easy way to append multiple
  objects as string representations to a StringBuilder.
  
  @param self  a StringBuilder
  @param value a value to append
  @return the StringBuilder on which this operation was invoked