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1
4 package com.tc.object.tx;
5
6 import com.tc.object.lockmanager.api.LockID;
7
8 import java.util.Collection  ;
9 import java.util.Collections ;
10 import java.util.HashMap ;
11 import java.util.HashSet ;
12 import java.util.Iterator ;
13 import java.util.Map ;
14 import java.util.Set ;
15
16 public class LockAccounting {
17
18 private final Map tx2Locks = new HashMap ();
19 private final Map lock2Txs = new HashMap ();
20
21 public synchronized Object dump() {
22 return "LockAccounting:\ntx2Locks=" + tx2Locks + "\nlock2Txs=" + lock2Txs + "/LockAccounting";
23 }
24
25 public String toString() {
26 return "LockAccounting[tx2Locks=" + tx2Locks + ", lock2Txs=" + lock2Txs + "]";
27 }
28
29 public synchronized void add(TransactionID txID, Collection lockIDs) {
30 getOrCreateSetFor(txID, tx2Locks).addAll(lockIDs);
31 for (Iterator i = lockIDs.iterator(); i.hasNext();) {
32 LockID lid = (LockID) i.next();
33 getOrCreateSetFor(lid, lock2Txs).add(txID);
34 }
35 }
36
37 public synchronized Collection getTransactionsFor(LockID lockID) {
38 Collection rv = new HashSet ();
39 Collection toAdd = (Collection ) lock2Txs.get(lockID);
40 if (toAdd != null) {
41 rv.addAll(toAdd);
42 }
43 return rv;
44 }
45
46 public synchronized Set acknowledge(TransactionID txID) {
48 Set completedLockIDs = null;
49 Set lockIDs = getSetFor(txID, tx2Locks);
50 if (lockIDs != null) {
51 for (Iterator i = lockIDs.iterator(); i.hasNext();) {
53 LockID lid = (LockID) i.next();
54 Set txIDs = getOrCreateSetFor(lid, lock2Txs);
55 if (!txIDs.remove(txID)) throw new AssertionError ("No lock=>transaction found for " + lid + ", " + txID);
56 if (txIDs.isEmpty()) {
57 lock2Txs.remove(lid);
58 if (completedLockIDs == null) {
59 completedLockIDs = new HashSet ();
60 }
61 completedLockIDs.add(lid);
62 }
63 }
64 }
65 tx2Locks.remove(txID);
66 return (completedLockIDs == null ? Collections.EMPTY_SET : completedLockIDs);
67 }
68
69 public synchronized boolean isEmpty() {
70 return tx2Locks.isEmpty() && lock2Txs.isEmpty();
71 }
72
73 private static Set getSetFor(Object key, Map m) {
74 return (Set ) m.get(key);
75 }
76
77 private static Set getOrCreateSetFor(Object key, Map m) {
78 Set rv = getSetFor(key, m);
79 if (rv == null) {
80 rv = new HashSet ();
81 m.put(key, rv);
82 }
83 return rv;
84 }
85
86 }
87 |
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