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1
5 package com.tc.objectserver.persistence.sleepycat;
6
7 import com.sleepycat.je.Database;
8 import com.sleepycat.je.DatabaseEntry;
9 import com.sleepycat.je.LockMode;
10 import com.sleepycat.je.OperationStatus;
11 import com.tc.logging.TCLogger;
12 import com.tc.objectserver.persistence.api.PersistenceTransaction;
13 import com.tc.objectserver.persistence.api.PersistenceTransactionProvider;
14 import com.tc.objectserver.persistence.api.PersistentSequence;
15 import com.tc.objectserver.persistence.sleepycat.SleepycatPersistor.SleepycatPersistorBase;
16 import com.tc.util.Conversion;
17 import com.tc.util.UUID;
18
19 class SleepycatSequence extends SleepycatPersistorBase implements PersistentSequence {
20 private static final String  UID_KEY = "UIDKEY-3475674589230";
21 private final long startValue;
22 private final DatabaseEntry key;
23 private final Database sequenceDB;
24 private final PersistenceTransactionProvider ptxp;
25 private final String uid;
26
27 SleepycatSequence(PersistenceTransactionProvider ptxp, TCLogger logger, long sequenceID, long startValue,
28 Database sequenceDB) {
29 this.ptxp = ptxp;
30 this.startValue = startValue;
31 this.sequenceDB = sequenceDB;
32 key = new DatabaseEntry();
33 key.setData(Conversion.long2Bytes(sequenceID));
34 this.uid = getOrCreateUID();
35 }
36
37 private String getOrCreateUID() {
38 PersistenceTransaction tx = ptxp.newTransaction();
39 String newuid;
40 try {
41 DatabaseEntry ukey = new DatabaseEntry();
42 ukey.setData(Conversion.string2Bytes(UID_KEY));
43 DatabaseEntry value = new DatabaseEntry();
44 OperationStatus status = this.sequenceDB.get(pt2nt(tx), ukey, value, LockMode.DEFAULT);
45
46 if (OperationStatus.SUCCESS.equals(status)) {
47 newuid = Conversion.bytes2String(value.getData());
48 } else if (OperationStatus.NOTFOUND.equals(status)) {
49 newuid = createUID();
50 value.setData(Conversion.string2Bytes(newuid));
51 status = this.sequenceDB.put(pt2nt(tx), ukey, value);
52 if (!OperationStatus.SUCCESS.equals(status)) { throw new DBException(
53 "Unable to store UID for SleepycatSequence: "
54 + newuid + "): " + status); }
55 } else {
56 throw new DBException("Unable to retrieve UID for SleepycatSequence: " + status);
57 }
58 tx.commit();
59 return newuid;
60 } catch (Exception t) {
61 abortOnError(tx);
62 t.printStackTrace();
63 throw (t instanceof DBException ? (DBException) t : new DBException(t));
64 }
65 }
66
67 private String createUID() {
68 UUID uuid = UUID.getUUID();
69 return uuid.toString();
70 }
71
72 public synchronized long next() {
73 return nextBatch(1);
74 }
75
76 public synchronized long nextBatch(int batchSize) {
77 if (batchSize < 1) throw new AssertionError ("Can't increment by a value less than 1.");
78 PersistenceTransaction tx = ptxp.newTransaction();
79 try {
80 DatabaseEntry value = new DatabaseEntry();
81 long currentValue = startValue;
82 OperationStatus status = this.sequenceDB.get(pt2nt(tx), key, value, LockMode.DEFAULT);
83
84 if (OperationStatus.SUCCESS.equals(status)) {
85 currentValue = Conversion.bytes2Long(value.getData());
86 } else if (!OperationStatus.NOTFOUND.equals(status)) {
87 throw new DBException("Unable to retrieve current value: " + status);
89 }
90
91 value.setData(Conversion.long2Bytes(currentValue + batchSize));
92 status = this.sequenceDB.put(pt2nt(tx), key, value);
93 if (!OperationStatus.SUCCESS.equals(status)) { throw new DBException("Unable to store current value: "
94 + (currentValue + batchSize) + "): "
95 + status); }
96 tx.commit();
97 return currentValue;
98 } catch (Exception t) {
99 abortOnError(tx);
100 t.printStackTrace();
101 throw (t instanceof DBException ? (DBException) t : new DBException(t));
102 }
103 }
104
105 public String getUID() {
106 return uid;
107 }
108
109 public void setNext(long next) {
110 PersistenceTransaction tx = ptxp.newTransaction();
111 try {
112 DatabaseEntry value = new DatabaseEntry();
113 long currentValue = startValue;
114 OperationStatus status = this.sequenceDB.get(pt2nt(tx), key, value, LockMode.DEFAULT);
115
116 if (OperationStatus.SUCCESS.equals(status)) {
117 currentValue = Conversion.bytes2Long(value.getData());
118 } else if (!OperationStatus.NOTFOUND.equals(status)) {
119 throw new DBException("Unable to retrieve current value: " + status);
121 }
122
123 if (currentValue > next) {
124 abortOnError(tx);
125 throw new AssertionError ("Cant setNext sequence to a value less than current: current = " + currentValue
126 + " next = " + next);
127 }
128
129 value.setData(Conversion.long2Bytes(next));
130 status = this.sequenceDB.put(pt2nt(tx), key, value);
131 if (!OperationStatus.SUCCESS.equals(status)) { throw new DBException("Unable to store next value: " + (next)
132 + "): " + status); }
133 tx.commit();
134 } catch (Exception t) {
135 abortOnError(tx);
136 t.printStackTrace();
137 throw (t instanceof DBException ? (DBException) t : new DBException(t));
138 }
139 }
140 } |
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