1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.scxml2.model;
18
19 import java.util.ArrayList;
20 import java.util.Collections;
21 import java.util.List;
22 import java.util.StringTokenizer;
23
24 /**
25 * The class in this SCXML object model that corresponds to the
26 * <transition> SCXML element. Transition rules are triggered
27 * by "events" and conditionalized via
28 * "guard-conditions".
29 *
30 */
31 public class Transition extends SimpleTransition implements DocumentOrder {
32
33 /**
34 * The document order of this transition
35 */
36 private int order;
37
38 /**
39 * Property that specifies the trigger(s) for this transition.
40 */
41 private String event;
42
43 /**
44 * This transition event descriptors
45 */
46 private List<String> events = Collections.emptyList();
47
48 /**
49 * Indicator for a event-less transition
50 */
51 private boolean noEvents;
52
53 /**
54 * Indicator for a transition matching all events (*)
55 */
56 private boolean allEvents;
57
58 /**
59 * Optional guard condition.
60 */
61 private String cond;
62
63 /**
64 * Constructor.
65 */
66 public Transition() {
67 super();
68 }
69
70
71 /**
72 * @return the document order of this transition
73 * @see DocumentOrder
74 */
75 @Override
76 public final int getOrder() {
77 return order;
78 }
79
80 /**
81 * Sets the document order of this transition
82 * @param order the document order
83 * @see DocumentOrder
84 */
85 public final void setOrder(int order) {
86 this.order = order;
87 }
88
89 /**
90 * Get the guard condition (may be null).
91 *
92 * @return Returns the cond.
93 */
94 public String getCond() {
95 return cond;
96 }
97
98 /**
99 * Set the guard condition.
100 *
101 * @param cond The cond to set.
102 */
103 public void setCond(final String cond) {
104 this.cond = cond;
105 }
106
107 /**
108 * Get the event that will trigger this transition (pending
109 * evaluation of the guard condition in favor).
110 *
111 * @return Returns the event.
112 */
113 public String getEvent() {
114 return event;
115 }
116
117 /**
118 * Set the event that will trigger this transition (pending
119 * evaluation of the guard condition in favor).
120 *
121 * @param event The event to set.
122 */
123 public void setEvent(final String event) {
124 this.event = event == null ? null : event.trim();
125 if (this.event != null) {
126 // 'event' is a space separated list of event descriptors
127 events = new ArrayList<String>();
128 StringTokenizer st = new StringTokenizer(this.event);
129 while (st.hasMoreTokens()) {
130 String token = st.nextToken();
131 if (token.equals("*")) {
132 events.clear();
133 events.add(token);
134 break;
135 }
136 else {
137 if (token.endsWith("*")) {
138 token = token.substring(0, token.length()-1);
139 }
140 if (token.endsWith(".")) {
141 token = token.substring(0, token.length()-1);
142 }
143 if (token.length() > 0) {
144 events.add(token);
145 }
146 }
147 }
148 }
149 else {
150 events = Collections.emptyList();
151 }
152 noEvents = events.isEmpty();
153 allEvents = !noEvents && events.get(0).equals("*");
154 }
155
156 /**
157 * @return The list of this transition event descriptors
158 */
159 public final List<String> getEvents() {
160 return events;
161 }
162
163 /**
164 * @return True if this transition is event-less
165 */
166 public final boolean isNoEventsTransition() {
167 return noEvents;
168 }
169
170 /**
171 * @return True if this transition matches any events (*)
172 */
173 public final boolean isAllEventsTransition() {
174 return allEvents;
175 }
176 }