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1
22 package org.jboss.ha.framework.server;
23
24 import java.util.ArrayList  ;
25 import java.util.List ;
26 import org.jboss.ha.framework.interfaces.DistributedReplicantManager;
27 import org.jboss.ha.framework.interfaces.DistributedReplicantManager.ReplicantListener;
28 import org.jboss.ha.framework.interfaces.HAPartition;
29 import java.io.Serializable ;
30 import EDU.oswego.cs.dl.util.concurrent.Latch;
31
32
46 public class HATarget
47 implements ReplicantListener
48 {
49 public static final int DISABLE_INVOCATIONS = 0;
50 public static final int MAKE_INVOCATIONS_WAIT = 1;
51 public static final int ENABLE_INVOCATIONS = 2;
52
53 protected String replicantName;
54 protected ArrayList replicants = new ArrayList ();
55 protected HAPartition partition = null;
56 protected org.jboss.logging.Logger log;
57 protected int clusterViewId = 0;
58 protected Serializable target;
59 protected int allowInvocationsStatus = 0;
60 protected Latch latch = null;
61
62 public HATarget(HAPartition partition,
63 String replicantName,
64 Serializable target,
65 int allowInvocations)
66 throws Exception
67 {
68 this.replicantName = replicantName;
69 this.target = target;
70 init ();
71 setInvocationsAuthorization (allowInvocations);
72 updateHAPartition(partition);
73 }
74
75 public void init() throws Exception
76 {
77 this.log = org.jboss.logging.Logger.getLogger(this.getClass());
78 }
79
80 public String toString()
81 {
82 StringBuffer buffer = new StringBuffer (super.toString());
83 buffer.append('{');
84 buffer.append("replicantName="+replicantName);
85 buffer.append("partition="+partition.getPartitionName());
86 buffer.append("clusterViewId="+clusterViewId);
87 buffer.append("allowInvocationsStatus="+allowInvocationsStatus);
88 buffer.append("replicants="+replicants);
89 buffer.append('}');
90 return buffer.toString();
91 }
92
93 public long getCurrentViewId()
94 {
95 return (long)clusterViewId;
96 }
97
98 public void destroy()
99 {
100 try
101 {
102 this.cleanExistenceInCurrentHAPartition();
103
104 setInvocationsAuthorization (HATarget.DISABLE_INVOCATIONS);
107 }
108 catch (Exception e)
109 {
110 log.error("failed to destroy", e);
111 }
112 }
113
114 public void disable()
118 {
119 try
120 {
121 if (this.partition != null)
122 {
123 log.debug ("Disabled called on HATarget");
124 this.partition.getDistributedReplicantManager().remove (this.replicantName);
125 }
126 }
127 catch (Exception e)
128 {
129 log.error("failed to disable", e);
130 }
131 }
132
133 public ArrayList getReplicants()
134 {
135 return replicants;
136 }
137
138 public void updateHAPartition(HAPartition partition) throws Exception
139 {
140 cleanExistenceInCurrentHAPartition();
141
142 this.partition = partition;
143 DistributedReplicantManager drm = partition.getDistributedReplicantManager();
144 drm.registerListener(this.replicantName, this);
145 drm.add(this.replicantName, this.target);
146 }
147
148 public synchronized void setInvocationsAuthorization (int status)
149 {
150 if (this.allowInvocationsStatus == status)
151 {
152 log.debug ("Invocation authorization called with no-op");
155 }
156 else
157 {
158 if (status == MAKE_INVOCATIONS_WAIT)
161 {
162 log.debug ("Invocation authorization called: MAKE_INVOCATIONS_WAIT");
163 latch = new Latch();
164 this.allowInvocationsStatus = status;
165 }
166 else
167 {
168 log.debug ("Invocation authorization called: " +
169 ((status==ENABLE_INVOCATIONS)?"ENABLE_INVOCATIONS":"DISABLE_INVOCATIONS") );
170 this.allowInvocationsStatus = status;
171 if (latch != null)
172 latch.release();
173 }
174 }
175 }
176
177 public boolean invocationsAllowed () throws InterruptedException
178 {
179 if (this.allowInvocationsStatus == ENABLE_INVOCATIONS)
180 return true;
181 else if (this.allowInvocationsStatus == DISABLE_INVOCATIONS)
182 return false;
183 else if (this.allowInvocationsStatus == MAKE_INVOCATIONS_WAIT)
184 {
185 latch.acquire ();
186
187 if (this.allowInvocationsStatus == ENABLE_INVOCATIONS)
191 return true;
192 else
193 return false;
194 }
195 else
196 return false;
197 }
198
199 protected void releaseCurrentLatch ()
200 {
201 latch.release ();
202 latch = null;
203 }
204
205 public HAPartition getAssociatedPartition ()
206 {
207 return this.partition;
208 }
209
210
212 public void replicantsChanged(String key, List newReplicants, int newReplicantsViewId)
213 {
214 if (log.isDebugEnabled())
215 log.debug("replicantsChanged '" + replicantName +
216 "' to " + (newReplicants==null? "0 (null)" : Integer.toString (newReplicants.size() ) ) +
217 " (intra-view id: " + newReplicantsViewId + ")");
218
219 synchronized(replicants)
220 {
221 replicants.clear();
224 if (newReplicants != null)
225 replicants.addAll(newReplicants);
226
227 this.clusterViewId = newReplicantsViewId;
228 }
229
230 }
231
232 protected void cleanExistenceInCurrentHAPartition()
233 {
234 if (this.partition != null)
235 {
236 try
237 {
238 DistributedReplicantManager drm = partition.getDistributedReplicantManager();
239 drm.unregisterListener(this.replicantName, this);
240 drm.remove(this.replicantName);
241 }
242 catch (Exception e)
243 {
244 log.error("failed to clean existence in current ha partition", e);
245 }
246 }
247 }
248 }
249 |
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