1 /*
2 * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.awt.event;
27
28 import java.awt.Adjustable;
29 import java.awt.AWTEvent;
30 import java.lang.annotation.Native;
31
32
33 /**
34 * The adjustment event emitted by Adjustable objects like
35 * {@link java.awt.Scrollbar} and {@link java.awt.ScrollPane}.
36 * When the user changes the value of the scrolling component,
37 * it receives an instance of {@code AdjustmentEvent}.
38 * <p>
39 * An unspecified behavior will be caused if the {@code id} parameter
40 * of any particular {@code AdjustmentEvent} instance is not
41 * in the range from {@code ADJUSTMENT_FIRST} to {@code ADJUSTMENT_LAST}.
42 * <p>
43 * The {@code type} of any {@code AdjustmentEvent} instance takes one of the following
44 * values:
45 * <ul>
46 * <li> {@code UNIT_INCREMENT}
47 * <li> {@code UNIT_DECREMENT}
48 * <li> {@code BLOCK_INCREMENT}
49 * <li> {@code BLOCK_DECREMENT}
50 * <li> {@code TRACK}
51 * </ul>
52 * Assigning the value different from listed above will cause an unspecified behavior.
53 * @see java.awt.Adjustable
54 * @see AdjustmentListener
55 *
56 * @author Amy Fowler
57 * @since 1.1
58 */
59 public class AdjustmentEvent extends AWTEvent {
60
61 /**
62 * Marks the first integer id for the range of adjustment event ids.
63 */
64 public static final int ADJUSTMENT_FIRST = 601;
65
66 /**
67 * Marks the last integer id for the range of adjustment event ids.
68 */
69 public static final int ADJUSTMENT_LAST = 601;
70
71 /**
72 * The adjustment value changed event.
73 */
74 public static final int ADJUSTMENT_VALUE_CHANGED = ADJUSTMENT_FIRST; //Event.SCROLL_LINE_UP
75
76 /**
77 * The unit increment adjustment type.
78 */
79 @Native public static final int UNIT_INCREMENT = 1;
80
81 /**
82 * The unit decrement adjustment type.
83 */
84 @Native public static final int UNIT_DECREMENT = 2;
85
86 /**
87 * The block decrement adjustment type.
88 */
89 @Native public static final int BLOCK_DECREMENT = 3;
90
91 /**
92 * The block increment adjustment type.
93 */
94 @Native public static final int BLOCK_INCREMENT = 4;
95
96 /**
97 * The absolute tracking adjustment type.
98 */
99 @Native public static final int TRACK = 5;
100
101 /**
102 * The adjustable object that fired the event.
103 *
104 * @serial
105 * @see #getAdjustable
106 */
107 @SuppressWarnings("serial") // Not statically typed as Serializable
108 Adjustable adjustable;
109
110 /**
111 * {@code value} will contain the new value of the
112 * adjustable object. This value will always be in a
113 * range associated adjustable object.
114 *
115 * @serial
116 * @see #getValue
117 */
118 int value;
119
120 /**
121 * The {@code adjustmentType} describes how the adjustable
122 * object value has changed.
123 * This value can be increased/decreased by a block or unit amount
124 * where the block is associated with page increments/decrements,
125 * and a unit is associated with line increments/decrements.
126 *
127 * @serial
128 * @see #getAdjustmentType
129 */
130 int adjustmentType;
131
132
133 /**
134 * The {@code isAdjusting} is true if the event is one
135 * of the series of multiple adjustment events.
136 *
137 * @since 1.4
138 * @serial
139 * @see #getValueIsAdjusting
140 */
141 boolean isAdjusting;
142
143
144 /*
145 * JDK 1.1 serialVersionUID
146 */
147 private static final long serialVersionUID = 5700290645205279921L;
148
149
150 /**
151 * Constructs an {@code AdjustmentEvent} object with the
152 * specified {@code Adjustable} source, event type,
153 * adjustment type, and value.
154 * <p> This method throws an
155 * {@code IllegalArgumentException} if {@code source}
156 * is {@code null}.
157 *
158 * @param source The {@code Adjustable} object where the
159 * event originated
160 * @param id An integer indicating the type of event.
161 * For information on allowable values, see
162 * the class description for {@link AdjustmentEvent}
163 * @param type An integer indicating the adjustment type.
164 * For information on allowable values, see
165 * the class description for {@link AdjustmentEvent}
166 * @param value The current value of the adjustment
167 * @throws IllegalArgumentException if {@code source} is null
168 * @see #getSource()
169 * @see #getID()
170 * @see #getAdjustmentType()
171 * @see #getValue()
172 */
173 public AdjustmentEvent(Adjustable source, int id, int type, int value) {
174 this(source, id, type, value, false);
175 }
176
177 /**
178 * Constructs an {@code AdjustmentEvent} object with the
179 * specified Adjustable source, event type, adjustment type, and value.
180 * <p> This method throws an
181 * {@code IllegalArgumentException} if {@code source}
182 * is {@code null}.
183 *
184 * @param source The {@code Adjustable} object where the
185 * event originated
186 * @param id An integer indicating the type of event.
187 * For information on allowable values, see
188 * the class description for {@link AdjustmentEvent}
189 * @param type An integer indicating the adjustment type.
190 * For information on allowable values, see
191 * the class description for {@link AdjustmentEvent}
192 * @param value The current value of the adjustment
193 * @param isAdjusting A boolean that equals {@code true} if the event is one
194 * of a series of multiple adjusting events,
195 * otherwise {@code false}
196 * @throws IllegalArgumentException if {@code source} is null
197 * @since 1.4
198 * @see #getSource()
199 * @see #getID()
200 * @see #getAdjustmentType()
201 * @see #getValue()
202 * @see #getValueIsAdjusting()
203 */
204 public AdjustmentEvent(Adjustable source, int id, int type, int value, boolean isAdjusting) {
205 super(source, id);
206 adjustable = source;
207 this.adjustmentType = type;
208 this.value = value;
209 this.isAdjusting = isAdjusting;
210 }
211
212 /**
213 * Returns the {@code Adjustable} object where this event originated.
214 *
215 * @return the {@code Adjustable} object where this event originated
216 */
217 public Adjustable getAdjustable() {
218 return adjustable;
219 }
220
221 /**
222 * Returns the current value in the adjustment event.
223 *
224 * @return the current value in the adjustment event
225 */
226 public int getValue() {
227 return value;
228 }
229
230 /**
231 * Returns the type of adjustment which caused the value changed
232 * event. It will have one of the following values:
233 * <ul>
234 * <li>{@link #UNIT_INCREMENT}
235 * <li>{@link #UNIT_DECREMENT}
236 * <li>{@link #BLOCK_INCREMENT}
237 * <li>{@link #BLOCK_DECREMENT}
238 * <li>{@link #TRACK}
239 * </ul>
240 * @return one of the adjustment values listed above
241 */
242 public int getAdjustmentType() {
243 return adjustmentType;
244 }
245
246 /**
247 * Returns {@code true} if this is one of multiple
248 * adjustment events.
249 *
250 * @return {@code true} if this is one of multiple
251 * adjustment events, otherwise returns {@code false}
252 * @since 1.4
253 */
254 public boolean getValueIsAdjusting() {
255 return isAdjusting;
256 }
257
258 public String paramString() {
259 String typeStr;
260 switch(id) {
261 case ADJUSTMENT_VALUE_CHANGED:
262 typeStr = "ADJUSTMENT_VALUE_CHANGED";
263 break;
264 default:
265 typeStr = "unknown type";
266 }
267 String adjTypeStr;
268 switch(adjustmentType) {
269 case UNIT_INCREMENT:
270 adjTypeStr = "UNIT_INCREMENT";
271 break;
272 case UNIT_DECREMENT:
273 adjTypeStr = "UNIT_DECREMENT";
274 break;
275 case BLOCK_INCREMENT:
276 adjTypeStr = "BLOCK_INCREMENT";
277 break;
278 case BLOCK_DECREMENT:
279 adjTypeStr = "BLOCK_DECREMENT";
280 break;
281 case TRACK:
282 adjTypeStr = "TRACK";
283 break;
284 default:
285 adjTypeStr = "unknown type";
286 }
287 return typeStr
288 + ",adjType="+adjTypeStr
289 + ",value="+value
290 + ",isAdjusting="+isAdjusting;
291 }
292 }