    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements.  See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache License, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License.  You may obtain a copy of the License at
    008     *
    009     *     http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the License for the specific language governing permissions and
    015     * limitations under the License.
    016     */
    017    package org.apache.commons.scxml.semantics;
    018
    019    /**
    020     * Errors reported by the default SCXMLSemantics implementation.
    021     *
    022     */
    023    public class ErrorConstants {
    024
    025        /**
    026         * Missing initial state for a composite state or for the scxml root.
    027         *
    028         * @see org.apache.commons.scxml.model.SCXML#getInitialState()
    029         * @see org.apache.commons.scxml.model.State#getInitial()
    030         */
    031        public static final String NO_INITIAL = "NO_INITIAL";
    032
    033        /**
    034         * An initial state for a composite state whose Transition does not.
    035         * Map to a descendant of the composite state.
    036         *
    037         */
    038        public static final String ILLEGAL_INITIAL = "ILLEGAL_INITIAL";
    039
    040        /**
    041         * Unknown action - unsupported executable content. List of supported.
    042         * actions: assign, cancel, elseif, else, if, log, send, var
    043         */
    044        public static final String UNKNOWN_ACTION = "UNKNOWN_ACTION";
    045
    046        /**
    047         * Illegal state machine configuration.
    048         * Either a parallel exists which does not have all its AND sub-states
    049         * active or there are multiple enabled OR states on the same level.
    050         */
    051        public static final String ILLEGAL_CONFIG = "ILLEGAL_CONFIG";
    052
    053        /**
    054         * Non-deterministic situation has occured - there are more than
    055         * one enabled transitions in conflict.
    056         *
    057         * @deprecated Non deterministic behavior is now resolved using
    058         *             state heirarchy and document order priorities.
    059         */
    060        public static final String NON_DETERMINISTIC = "NON_DETERMINISTIC";
    061
    062        /**
    063         * A variable referred to by assign name attribute is undefined.
    064         */
    065        public static final String UNDEFINED_VARIABLE = "UNDEFINED_VARIABLE";
    066
    067        /**
    068         * An expression language error.
    069         */
    070        public static final String EXPRESSION_ERROR = "EXPRESSION_ERROR";
    071
    072        //---------------------------------------------- STATIC CONSTANTS ONLY
    073
    074        /**
    075         * Discourage instantiation.
    076         */
    077        private ErrorConstants() {
    078            super(); // humor checkstyle
    079        }
    080
    081    }