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1
56
57 package org.objectstyle.cayenne.event;
58
59 import java.util.Collection  ;
60 import java.util.HashSet ;
61 import java.util.Iterator ;
62 import java.util.Map ;
63 import java.util.Set ;
64 import java.util.WeakHashMap ;
65
66 import org.apache.log4j.Logger;
67 import org.objectstyle.cayenne.event.EventManager.Dispatch;
68 import org.objectstyle.cayenne.util.Invocation;
69
70
80 class DispatchQueue {
81 private static Logger logObj = Logger.getLogger(DispatchQueue.class);
82
83
85 private Set subjectInvocations = new HashSet ();
86 private Map invocationsBySender = new WeakHashMap ();
87
88
92 synchronized void dispatchEvent(Dispatch dispatch) {
93 dispatchEvent(subjectInvocations, dispatch);
95
96 Object sender = dispatch.getSender();
98 dispatchEvent(invocationsForSender(sender, false), dispatch);
99 }
100
101 synchronized void addInvocation(Invocation invocation, Object sender) {
102 if (sender == null) {
103 subjectInvocations.add(invocation);
104 }
105 else {
106 invocationsForSender(sender, true).add(invocation);
107 }
108 }
109
110 synchronized boolean removeInvocations(Object listener, Object sender) {
111
112 if (sender != null) {
114 return removeInvocations(invocationsForSender(sender, false), listener);
115 }
116
117 boolean didRemove = false;
118
119 didRemove = removeInvocations(subjectInvocations, listener);
121
122 Iterator sets = invocationsBySender.values().iterator();
123 while (sets.hasNext()) {
124 Collection senderInvocations = (Collection ) sets.next();
125 if (senderInvocations == null) {
126 continue;
127 }
128
129 Iterator it = senderInvocations.iterator();
130 while (it.hasNext()) {
131 Invocation invocation = (Invocation) it.next();
132 if (invocation.getTarget() == listener) {
133 it.remove();
134 didRemove = true;
135 }
136 }
137 }
138
139 return didRemove;
140 }
141
142 private Collection invocationsForSender(Object sender, boolean create) {
143 Collection senderInvocations = (Collection ) invocationsBySender.get(sender);
144 if (create && senderInvocations == null) {
145 senderInvocations = new HashSet ();
146 invocationsBySender.put(sender, senderInvocations);
147 }
148
149 return senderInvocations;
150 }
151
152 private boolean removeInvocations(Collection invocations, Object listener) {
154 if (invocations == null || invocations.isEmpty()) {
155 return false;
156 }
157
158 boolean didRemove = false;
159
160 Iterator invocationsIt = invocations.iterator();
161 while (invocationsIt.hasNext()) {
162 Invocation invocation = (Invocation) invocationsIt.next();
163 if (invocation.getTarget() == listener) {
164 invocationsIt.remove();
165 didRemove = true;
166 }
167 }
168
169 return didRemove;
170 }
171
172 private void dispatchEvent(Collection invocations, Dispatch dispatch) {
174 if (invocations == null || invocations.isEmpty()) {
175 return;
176 }
177
178 Iterator it = invocations.iterator();
179 while (it.hasNext()) {
180 Invocation invocation = (Invocation) it.next();
181
182 if (!dispatch.fire(invocation)) {
184 it.remove();
185 logObj.debug(
186 "Failed invocation, removing: " + invocation.getMethod().getName());
187 }
188 }
189 }
190 }
191 |
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