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 */
017package org.apache.commons.scxml2;
018
019/**
020 * The SCXML I/O Processor provides the interface for either an internal process or an external system or invoked child
021 * SCXML process ({@link org.apache.commons.scxml2.invoke.Invoker}) to send events into the SCXML processor queue.
022 */
023public interface SCXMLIOProcessor {
024
025    /**
026     * The name of the default SCXML I/O Event Processor
027     */
028    String DEFAULT_EVENT_PROCESSOR = "http://www.w3.org/TR/scxml/#SCXMLEventProcessor";
029
030    /**
031     * Prefix for SCXML I/O Event Processor aliases
032     */
033    String EVENT_PROCESSOR_ALIAS_PREFIX = "#_";
034
035    /**
036     * Default SCXML I/O Event Processor alias
037     */
038    String SCXML_EVENT_PROCESSOR = "scxml";
039
040    /**
041     * Prefix for SCXML I/O (own) Session external Event processor
042     */
043    String SCXML_SESSION_EVENT_PROCESSOR_PREFIX = EVENT_PROCESSOR_ALIAS_PREFIX + "scxml_";
044
045    /**
046     * The name of the internal Event Processor
047     */
048    String INTERNAL_EVENT_PROCESSOR = EVENT_PROCESSOR_ALIAS_PREFIX + "internal";
049
050    /**
051     * The name of the parent Event Processor
052     */
053    String PARENT_EVENT_PROCESSOR = EVENT_PROCESSOR_ALIAS_PREFIX + "parent";
054
055    /**
056     * Send an event into the SCXML processor queue
057     * <p>
058     * @param event the event to send
059     */
060    void addEvent(TriggerEvent event);
061}