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Java > Open Source Codes > com > tc > objectserver > handler > ApplyTransactionChangeHandler


1 /*
2  * All content copyright (c) 2003-2006 Terracotta, Inc., except as may otherwise be noted in a separate copyright
3  * notice. All rights reserved.
4  */
5 package com.tc.objectserver.handler;
6
7 import com.tc.async.api.AbstractEventHandler;
8 import com.tc.async.api.ConfigurationContext;
9 import com.tc.async.api.EventContext;
10 import com.tc.async.api.Sink;
11 import com.tc.object.gtx.GlobalTransactionID;
12 import com.tc.object.lockmanager.api.Notify;
13 import com.tc.object.tx.ServerTransactionID;
14 import com.tc.objectserver.api.ObjectInstanceMonitor;
15 import com.tc.objectserver.context.ApplyTransactionContext;
16 import com.tc.objectserver.context.BroadcastChangeContext;
17 import com.tc.objectserver.core.api.ServerConfigurationContext;
18 import com.tc.objectserver.gtx.ServerGlobalTransactionManager;
19 import com.tc.objectserver.lockmanager.api.LockManager;
20 import com.tc.objectserver.lockmanager.api.NotifiedWaiters;
21 import com.tc.objectserver.managedobject.BackReferences;
22 import com.tc.objectserver.tx.ServerTransaction;
23 import com.tc.objectserver.tx.ServerTransactionManager;
24 import com.tc.objectserver.tx.TransactionalObjectManager;
25
26 import java.util.Iterator JavaDoc;
27 import java.util.LinkedList JavaDoc;
28
29 /**
30  * Applies all the changes in a transaction then releases the objects and passes the changes off to be broadcast to the
31  * interested client sessions
32  *
33  * @author steve
34  */
35 public class ApplyTransactionChangeHandler extends AbstractEventHandler {
36   private ServerTransactionManager transactionManager;
37   private LockManager lockManager;
38   private Sink broadcastChangesSink;
39   private final ObjectInstanceMonitor instanceMonitor;
40   private final ServerGlobalTransactionManager gtxm;
41   private TransactionalObjectManager txnObjectMgr;
42
43   public ApplyTransactionChangeHandler(ObjectInstanceMonitor instanceMonitor, ServerGlobalTransactionManager gtxm) {
44     this.instanceMonitor = instanceMonitor;
45     this.gtxm = gtxm;
46   }
47
48   public void handleEvent(EventContext context) {
49     ApplyTransactionContext atc = (ApplyTransactionContext) context;
50     final ServerTransaction txn = atc.getTxn();
51
52     NotifiedWaiters notifiedWaiters = new NotifiedWaiters();
53     final ServerTransactionID stxnID = txn.getServerTransactionID();
54     final BackReferences includeIDs = new BackReferences();
55     
56     //TODO::Comeback and fix for passive
57 GlobalTransactionID gtxnID = gtxm.createGlobalTransactionID(stxnID);
58
59     // XXX::FIXME:: this needsApply() call only returns false after the txn is commited. If we see the same txn twice
60 // before commit, then we may apply it twice, though in the current state of affairs that is not possible (unless
61 // ofcourse there is a bug !)
62 if (gtxm.needsApply(stxnID)) {
63       transactionManager.apply(gtxnID, txn, atc.getObjects(), includeIDs, instanceMonitor);
64       txnObjectMgr.applyTransactionComplete(stxnID);
65     } else {
66       transactionManager.skipApplyAndCommit(txn);
67       getLogger().warn("Not applying previously applied transaction: " + stxnID);
68     }
69
70     if (!txn.isPassive()) {
71       for (Iterator JavaDoc i = txn.addNotifiesTo(new LinkedList JavaDoc()).iterator(); i.hasNext();) {
72         Notify notify = (Notify) i.next();
73         lockManager.notify(notify.getLockID(), txn.getChannelID(), notify.getThreadID(), notify.getIsAll(),
74                            notifiedWaiters);
75       }
76       broadcastChangesSink.add(new BroadcastChangeContext(gtxnID, txn, gtxm.getLowGlobalTransactionIDWatermark(),
77                                                           notifiedWaiters, includeIDs));
78     }
79   }
80
81   public void initialize(ConfigurationContext context) {
82     super.initialize(context);
83     ServerConfigurationContext scc = (ServerConfigurationContext) context;
84     this.transactionManager = scc.getTransactionManager();
85     this.broadcastChangesSink = scc.getStage(ServerConfigurationContext.BROADCAST_CHANGES_STAGE).getSink();
86     this.txnObjectMgr = scc.getTransactionalObjectManager();
87     this.lockManager = scc.getLockManager();
88   }
89 }
90
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