1
2
3
4
5
6
7
8
9
10
11
12
13
14 package org.eclipse.jetty.util.component;
15 import java.lang.ref.WeakReference;
16 import java.util.EventListener;
17 import java.util.concurrent.CopyOnWriteArrayList;
18
19 import org.eclipse.jetty.util.LazyList;
20 import org.eclipse.jetty.util.log.Log;
21 import org.eclipse.jetty.util.log.Logger;
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41 public class Container
42 {
43 private static final Logger LOG = Log.getLogger(Container.class);
44 private final CopyOnWriteArrayList<Container.Listener> _listeners=new CopyOnWriteArrayList<Container.Listener>();
45
46 public void addEventListener(Container.Listener listener)
47 {
48 _listeners.add(listener);
49 }
50
51 public void removeEventListener(Container.Listener listener)
52 {
53 _listeners.remove(listener);
54 }
55
56
57
58
59
60
61
62
63 public void update(Object parent, Object oldChild, final Object child, String relationship)
64 {
65 if (oldChild!=null && !oldChild.equals(child))
66 remove(parent,oldChild,relationship);
67 if (child!=null && !child.equals(oldChild))
68 add(parent,child,relationship);
69 }
70
71
72
73
74
75
76
77
78
79 public void update(Object parent, Object oldChild, final Object child, String relationship,boolean addRemove)
80 {
81 if (oldChild!=null && !oldChild.equals(child))
82 {
83 remove(parent,oldChild,relationship);
84 if (addRemove)
85 removeBean(oldChild);
86 }
87
88 if (child!=null && !child.equals(oldChild))
89 {
90 if (addRemove)
91 addBean(child);
92 add(parent,child,relationship);
93 }
94 }
95
96
97
98
99
100
101
102
103
104 public void update(Object parent, Object[] oldChildren, final Object[] children, String relationship)
105 {
106 update(parent,oldChildren,children,relationship,false);
107 }
108
109
110
111
112
113
114
115
116
117
118 public void update(Object parent, Object[] oldChildren, final Object[] children, String relationship, boolean addRemove)
119 {
120 Object[] newChildren = null;
121 if (children!=null)
122 {
123 newChildren = new Object[children.length];
124
125 for (int i=children.length;i-->0;)
126 {
127 boolean new_child=true;
128 if (oldChildren!=null)
129 {
130 for (int j=oldChildren.length;j-->0;)
131 {
132 if (children[i]!=null && children[i].equals(oldChildren[j]))
133 {
134 oldChildren[j]=null;
135 new_child=false;
136 }
137 }
138 }
139 if (new_child)
140 newChildren[i]=children[i];
141 }
142 }
143
144 if (oldChildren!=null)
145 {
146 for (int i=oldChildren.length;i-->0;)
147 {
148 if (oldChildren[i]!=null)
149 {
150 remove(parent,oldChildren[i],relationship);
151 if (addRemove)
152 removeBean(oldChildren[i]);
153 }
154 }
155 }
156
157 if (newChildren!=null)
158 {
159 for (int i=0;i<newChildren.length;i++)
160 if (newChildren[i]!=null)
161 {
162 if (addRemove)
163 addBean(newChildren[i]);
164 add(parent,newChildren[i],relationship);
165 }
166 }
167 }
168
169
170 public void addBean(Object obj)
171 {
172 if (_listeners!=null)
173 {
174 for (int i=0; i<LazyList.size(_listeners); i++)
175 {
176 Listener listener=(Listener)LazyList.get(_listeners, i);
177 listener.addBean(obj);
178 }
179 }
180 }
181
182
183 public void removeBean(Object obj)
184 {
185 if (_listeners!=null)
186 {
187 for (int i=0; i<LazyList.size(_listeners); i++)
188 ((Listener)LazyList.get(_listeners, i)).removeBean(obj);
189 }
190 }
191
192
193
194
195
196
197
198 private void add(Object parent, Object child, String relationship)
199 {
200 if (LOG.isDebugEnabled())
201 LOG.debug("Container "+parent+" + "+child+" as "+relationship);
202 if (_listeners!=null)
203 {
204 Relationship event=new Relationship(this,parent,child,relationship);
205 for (int i=0; i<LazyList.size(_listeners); i++)
206 ((Listener)LazyList.get(_listeners, i)).add(event);
207 }
208 }
209
210
211
212
213
214
215
216 private void remove(Object parent, Object child, String relationship)
217 {
218 if (LOG.isDebugEnabled())
219 LOG.debug("Container "+parent+" - "+child+" as "+relationship);
220 if (_listeners!=null)
221 {
222 Relationship event=new Relationship(this,parent,child,relationship);
223 for (int i=0; i<LazyList.size(_listeners); i++)
224 ((Listener)LazyList.get(_listeners, i)).remove(event);
225 }
226 }
227
228
229
230
231
232 public static class Relationship
233 {
234 private final WeakReference<Object> _parent;
235 private final WeakReference<Object> _child;
236 private String _relationship;
237 private Container _container;
238
239 private Relationship(Container container, Object parent,Object child, String relationship)
240 {
241 _container=container;
242 _parent=new WeakReference<Object>(parent);
243 _child=new WeakReference<Object>(child);
244 _relationship=relationship;
245 }
246
247 public Container getContainer()
248 {
249 return _container;
250 }
251
252 public Object getChild()
253 {
254 return _child.get();
255 }
256
257 public Object getParent()
258 {
259 return _parent.get();
260 }
261
262 public String getRelationship()
263 {
264 return _relationship;
265 }
266
267 @Override
268 public String toString()
269 {
270 return _parent+"---"+_relationship+"-->"+_child;
271 }
272
273 @Override
274 public int hashCode()
275 {
276 return _parent.hashCode()+_child.hashCode()+_relationship.hashCode();
277 }
278
279 @Override
280 public boolean equals(Object o)
281 {
282 if (o==null || !(o instanceof Relationship))
283 return false;
284 Relationship r = (Relationship)o;
285 return r._parent.get()==_parent.get() && r._child.get()==_child.get() && r._relationship.equals(_relationship);
286 }
287 }
288
289
290
291
292
293 public interface Listener extends EventListener
294 {
295 public void addBean(Object bean);
296 public void removeBean(Object bean);
297 public void add(Container.Relationship relationship);
298 public void remove(Container.Relationship relationship);
299 }
300 }