code: @Nullable
    public static CharSequence getNotNull (@Nullable final CharSequence s, final CharSequence sDefaultIfNull)
    {
      return s == null ? sDefaultIfNull : s;
    }
docs: Get the passed {@link CharSequence} but never return <code>null</code>. If
  the passed parameter is <code>null</code> the second parameter is returned.
  
  @param s
  The parameter to be not <code>null</code>.
  @param sDefaultIfNull
  The value to be used of the first parameter is <code>null</code>. May
  be <code>null</code> but in this case the call to this method is
  obsolete.
  @return The passed default value if the string is <code>null</code>,
  otherwise the input {@link CharSequence}.