private static boolean booleanField(String fieldName, boolean defaultValue, Inspector object) {
        Inspector value = object.field(fieldName);
        if ( ! value.valid()) return defaultValue;
        return value.asBool();
    }
Returns the previously active generation at the point when this application was created.
config-model-api/src/main/java/com/yahoo/config/application/api/ApplicationMetaData.java