public void init() throws IOException {
        LOGGER.info("Un-marshaling person attributes from the config file [{}]", this.personAttributesConfigFile);
        try (val in = personAttributesConfigFile.getInputStream()) {
            val backingMap = jacksonObjectMapper.readValue(in, Map.class);
            LOGGER.debug("Person attributes have been successfully read into the map ");
            setBackingMap(backingMap);
        }
    }
Init method un-marshals JSON representation of the person attributes.

@throws IOException invalid config file URI
support/cas-server-support-person-directory-core/src/main/java/org/apereo/cas/persondir/JsonPersonAttributeDao.java