public String setValue(Field field, String value) {
        return setValue(field.getName(), value);
    }
Sets the value of the given field. Any existing value for that field is
replaced.

@param field
    The field whose value should be assigned.

@param value
    The value to assign to the given field.

@return
    The previous value of the field, or null if the value of the field
    was not previously defined.
guacamole-ext/src/main/java/org/apache/guacamole/net/auth/credentials/UserCredentials.java