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1 package org.jacorb.notification.queue;
2
3
23
24 import java.util.ArrayList  ;
25 import java.util.Collections ;
26 import java.util.Iterator ;
27 import java.util.List ;
28
29 import org.jacorb.notification.interfaces.Message;
30
31 import EDU.oswego.cs.dl.util.concurrent.Heap;
32
33
41
42 public class BoundedPriorityEventQueue extends AbstractBoundedEventQueue
43 {
44 private Heap heap_;
45
46 private long counter_ = 0;
47
48 private final int maxCapacity_;
49
50
52 public BoundedPriorityEventQueue(int maxSize,
53 EventQueueOverflowStrategy overflowStrategy)
54 {
55 super(maxSize, overflowStrategy, new Object ());
56
57 maxCapacity_ = maxSize;
58
59 heap_ = newHeap();
60 }
61
62
64 private Heap newHeap()
65 {
66 return new Heap2(maxCapacity_, QueueUtil.DESCENDING_PRIORITY_COMPARATOR);
67 }
68
69 protected Message getNextElement()
70 {
71 return ((HeapEntry)heap_.extract()).event_;
72 }
73
74
75 protected Message getEarliestTimeout()
76 {
77 List _all = getAllElementsInternal();
78
79 Collections.sort(_all, QueueUtil.ASCENDING_TIMEOUT_COMPARATOR);
80
81 HeapEntry _earliest = (HeapEntry)_all.remove(0);
82
83 Heap _newHeap = newHeap();
84
85 Iterator i = _all.iterator();
86
87 while (i.hasNext())
88 {
89 HeapEntry e = (HeapEntry)i.next();
90 _newHeap.insert(e);
91 }
92
93 heap_ = _newHeap;
94
95 return _earliest.event_;
96 }
97
98
99 protected Message getOldestElement()
100 {
101 List _all = getAllElementsInternal();
102
103 Collections.sort(_all, QueueUtil.ASCENDING_AGE_COMPARATOR);
104
105 HeapEntry _oldest = (HeapEntry)_all.remove(0);
106
107 Heap _newHeap = newHeap();
108
109 Iterator i = _all.iterator();
110
111 while (i.hasNext())
112 {
113 HeapEntry e = (HeapEntry)i.next();
114 _newHeap.insert(e);
115 }
116
117 return _oldest.event_;
118 }
119
120
121 protected Message getYoungestElement()
122 {
123 List _all = getAllElementsInternal();
124
125 Collections.sort(_all, QueueUtil.DESCENDING_AGE_COMPARATOR);
126
127 HeapEntry _youngest = (HeapEntry)_all.remove(0);
128
129 Heap _newHeap = newHeap();
130
131 Iterator i = _all.iterator();
132
133 while (i.hasNext())
134 {
135 HeapEntry e = (HeapEntry)i.next();
136 _newHeap.insert(e);
137 }
138
139 heap_ = _newHeap;
140
141 return _youngest.event_;
142 }
143
144
145 protected Message getLeastPriority()
146 {
147 List _all = getAllElementsInternal();
148
149 Collections.sort(_all, QueueUtil.ASCENDING_PRIORITY_COMPARATOR);
150
151 HeapEntry _leastPriority = (HeapEntry)_all.remove(0);
152
153 Heap _newHeap = newHeap();
154
155 Iterator i = _all.iterator();
156
157 while (i.hasNext())
158 {
159 HeapEntry e = (HeapEntry)i.next();
160 _newHeap.insert(e);
161 }
162
163 heap_ = _newHeap;
164
165 return _leastPriority.event_;
166 }
167
168
169 protected Message[] getElements(int max)
170 {
171 List _events = new ArrayList ();
172 Object _element;
173
174 while ((_element = heap_.extract()) != null && (_events.size() <= max))
175 {
176 _events.add(((HeapEntry)_element).event_);
177 }
178
179 return (Message[])
180 _events.toArray(QueueUtil.MESSAGE_ARRAY_TEMPLATE);
181 }
182
183
184 protected void addElement(Message event)
185 {
186 heap_.insert(new HeapEntry(event, counter_++));
187 }
188
189
190 private List getAllElementsInternal()
191 {
192 List _events = new ArrayList ();
193 Object _element;
194
195 while ((_element = heap_.extract()) != null)
196 {
197 _events.add(_element);
198 }
199
200 heap_.clear();
201
202 return _events;
203 }
204
205
206 protected Message[] getAllElements()
207 {
208 List _all = getAllElementsInternal();
209
210 Message[] _ret = new Message[_all.size()];
211
212 Iterator i = _all.iterator();
213
214 int x = 0;
215 while (i.hasNext())
216 {
217 HeapEntry e = (HeapEntry)i.next();
218 _ret[x++] = e.event_;
219 }
220
221 return _ret;
222 }
223
224
225 public boolean isEmpty()
226 {
227 return (getSize() == 0);
228 }
229
230
231 public int getSize()
232 {
233 return heap_.size();
234 }
235
236 public String toString()
237 {
238 return heap_.toString();
239 }
240 }
241 |
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