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1
11
12 package org.eclipse.ui.internal.contexts;
13
14 import java.util.ArrayList  ;
15 import java.util.HashSet ;
16 import java.util.List ;
17 import java.util.Set ;
18
19 import org.eclipse.ui.contexts.ContextEvent;
20 import org.eclipse.ui.contexts.IContext;
21 import org.eclipse.ui.contexts.IContextListener;
22 import org.eclipse.ui.contexts.NotDefinedException;
23 import org.eclipse.ui.internal.util.Util;
24
25 final class Context implements IContext {
26
27 private final static int HASH_FACTOR = 89;
28
29 private final static int HASH_INITIAL = Context.class.getName().hashCode();
30
31 private final static Set strongReferences = new HashSet ();
32
33 private List contextListeners;
34
35 private boolean defined;
36
37 private boolean enabled;
38
39 private transient int hashCode;
40
41 private transient boolean hashCodeComputed;
42
43 private String id;
44
45 private String name;
46
47 private String parentId;
48
49 private transient String string;
50
51 Context(String id) {
52 if (id == null) throw new NullPointerException ();
53
54 this.id = id;
55 }
56
57 public void addContextListener(IContextListener contextListener) {
58 if (contextListener == null) throw new NullPointerException ();
59
60 if (contextListeners == null) contextListeners = new ArrayList ();
61
62 if (!contextListeners.contains(contextListener))
63 contextListeners.add(contextListener);
64
65 strongReferences.add(this);
66 }
67
68 public int compareTo(Object object) {
69 Context castedObject = (Context) object;
70 int compareTo = Util.compare(defined, castedObject.defined);
71
72 if (compareTo == 0) {
73 compareTo = Util.compare(enabled, castedObject.enabled);
74
75 if (compareTo == 0) {
76 compareTo = Util.compare(id, castedObject.id);
77
78 if (compareTo == 0) {
79 compareTo = Util.compare(name, castedObject.name);
80
81 if (compareTo == 0)
82 compareTo = Util.compare(parentId,
83 castedObject.parentId);
84 }
85 }
86 }
87
88 return compareTo;
89 }
90
91 public boolean equals(Object object) {
92 if (!(object instanceof Context)) return false;
93
94 Context castedObject = (Context) object;
95 boolean equals = true;
96 equals &= Util.equals(defined, castedObject.defined);
97 equals &= Util.equals(enabled, castedObject.enabled);
98 equals &= Util.equals(id, castedObject.id);
99 equals &= Util.equals(name, castedObject.name);
100 equals &= Util.equals(parentId, castedObject.parentId);
101 return equals;
102 }
103
104 void fireContextChanged(ContextEvent contextEvent) {
105 if (contextEvent == null) throw new NullPointerException ();
106
107 if (contextListeners != null)
108 for (int i = 0; i < contextListeners.size(); i++)
109 ((IContextListener) contextListeners.get(i))
110 .contextChanged(contextEvent);
111 }
112
113 public String getId() {
114 return id;
115 }
116
117 public String getName() throws NotDefinedException {
118 if (!defined)
119 throw new NotDefinedException(
120 "Cannot get the name from an undefined context.");
122 return name;
123 }
124
125 public String getParentId() throws NotDefinedException {
126 if (!defined)
127 throw new NotDefinedException(
128 "Cannot get the parent identifier from an undefined context.");
130 return parentId;
131 }
132
133 public int hashCode() {
134 if (!hashCodeComputed) {
135 hashCode = HASH_INITIAL;
136 hashCode = hashCode * HASH_FACTOR + Util.hashCode(defined);
137 hashCode = hashCode * HASH_FACTOR + Util.hashCode(enabled);
138 hashCode = hashCode * HASH_FACTOR + Util.hashCode(id);
139 hashCode = hashCode * HASH_FACTOR + Util.hashCode(name);
140 hashCode = hashCode * HASH_FACTOR + Util.hashCode(parentId);
141 hashCodeComputed = true;
142 }
143
144 return hashCode;
145 }
146
147 public boolean isDefined() {
148 return defined;
149 }
150
151 public boolean isEnabled() {
152 return enabled;
153 }
154
155 public void removeContextListener(IContextListener contextListener) {
156 if (contextListener == null) throw new NullPointerException ();
157
158 if (contextListeners != null) contextListeners.remove(contextListener);
159
160 if (contextListeners.isEmpty()) strongReferences.remove(this);
161 }
162
163 boolean setDefined(boolean defined) {
164 if (defined != this.defined) {
165 this.defined = defined;
166 hashCodeComputed = false;
167 hashCode = 0;
168 string = null;
169 return true;
170 }
171
172 return false;
173 }
174
175 boolean setEnabled(boolean enabled) {
176 if (enabled != this.enabled) {
177 this.enabled = enabled;
178 hashCodeComputed = false;
179 hashCode = 0;
180 string = null;
181 return true;
182 }
183
184 return false;
185 }
186
187 boolean setName(String name) {
188 if (!Util.equals(name, this.name)) {
189 this.name = name;
190 hashCodeComputed = false;
191 hashCode = 0;
192 string = null;
193 return true;
194 }
195
196 return false;
197 }
198
199 boolean setParentId(String parentId) {
200 if (!Util.equals(parentId, this.parentId)) {
201 this.parentId = parentId;
202 hashCodeComputed = false;
203 hashCode = 0;
204 string = null;
205 return true;
206 }
207
208 return false;
209 }
210
211 public String toString() {
212 if (string == null) {
213 final StringBuffer stringBuffer = new StringBuffer ();
214 stringBuffer.append('[');
215 stringBuffer.append(defined);
216 stringBuffer.append(',');
217 stringBuffer.append(enabled);
218 stringBuffer.append(',');
219 stringBuffer.append(id);
220 stringBuffer.append(',');
221 stringBuffer.append(name);
222 stringBuffer.append(',');
223 stringBuffer.append(parentId);
224 stringBuffer.append(']');
225 string = stringBuffer.toString();
226 }
227
228 return string;
229 }
230 }
231 |
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