code: public static String replaceAllSafe (@Nullable final String sInputString,
                                         @Nonnull final String sSearchText,
                                         @Nullable final CharSequence aReplacementText)
    {
      return replaceAll (sInputString, sSearchText, getNotNull (aReplacementText, ""));
    }
docs: Same as {@link #replaceAll(String, String, CharSequence)} but allowing for a
  <code>null</code> new-value, which is than interpreted as an empty string
  instead.
  
  @param sInputString
  The input string where the text should be replace. If this parameter
  is <code>null</code> or empty, no replacement is done.
  @param sSearchText
  The string to be replaced. May neither be <code>null</code> nor empty.
  @param aReplacementText
  The string with the replacement. May be <code>null</code> or empty.
  @return The input string as is, if the input string is empty or if the string
  to be replaced is not contained.