public String filterStrict(String input)
            throws GuacamoleTokenUndefinedException {
        return filter(input, true);
    }
Filters the given string, replacing any tokens with their corresponding
values. If any token in the given string has no defined value within
this TokenFilter, a GuacamoleTokenUndefinedException will be thrown.

@param input
    The string to filter.

@return
    A copy of the input string, with any tokens replaced with their
    corresponding values.

@throws GuacamoleTokenUndefinedException
    If at least one token in the given string has no corresponding
    value.
guacamole-ext/src/main/java/org/apache/guacamole/token/TokenFilter.java