01: package com.quadcap.sql.lock;
02:
03: /* Copyright 1999 - 2003 Quadcap Software. All rights reserved.
04: *
05: * This software is distributed under the Quadcap Free Software License.
06: * This software may be used or modified for any purpose, personal or
07: * commercial. Open Source redistributions are permitted. Commercial
08: * redistribution of larger works derived from, or works which bundle
09: * this software requires a "Commercial Redistribution License"; see
10: * http://www.quadcap.com/purchase.
11: *
12: * Redistributions qualify as "Open Source" under one of the following terms:
13: *
14: * Redistributions are made at no charge beyond the reasonable cost of
15: * materials and delivery.
16: *
17: * Redistributions are accompanied by a copy of the Source Code or by an
18: * irrevocable offer to provide a copy of the Source Code for up to three
19: * years at the cost of materials and delivery. Such redistributions
20: * must allow further use, modification, and redistribution of the Source
21: * Code under substantially the same terms as this license.
22: *
23: * Redistributions of source code must retain the copyright notices as they
24: * appear in each source code file, these license terms, and the
25: * disclaimer/limitation of liability set forth as paragraph 6 below.
26: *
27: * Redistributions in binary form must reproduce this Copyright Notice,
28: * these license terms, and the disclaimer/limitation of liability set
29: * forth as paragraph 6 below, in the documentation and/or other materials
30: * provided with the distribution.
31: *
32: * The Software is provided on an "AS IS" basis. No warranty is
33: * provided that the Software is free of defects, or fit for a
34: * particular purpose.
35: *
36: * Limitation of Liability. Quadcap Software shall not be liable
37: * for any damages suffered by the Licensee or any third party resulting
38: * from use of the Software.
39: */
40:
41: import com.quadcap.util.collections.LongMap;
42:
43: import com.quadcap.util.Debug;
44: import com.quadcap.util.Util;
45:
46: /**
47: * A pool for transactions, to reduce gc thrashing
48: *
49: * @author Stan Bailes
50: */
51: public class TransactionPool extends ObjectPool {
52: /**
53: * Keep active transactions in this map
54: */
55: LongMap map = new LongMap(13);
56:
57: /**
58: * Create and initialize the pool
59: */
60: public TransactionPool() {
61: super (new Transaction());
62: }
63:
64: /**
65: * Get a new transaction from the pool
66: */
67: public PooledObject get(long transId) {
68: Transaction trans = (Transaction) map.get(transId);
69: if (trans == null) {
70: trans = (Transaction) (super .get());
71: trans.init(transId);
72: map.put(transId, trans);
73: }
74: return trans;
75: }
76:
77: /**
78: * Find an existing transaction. Return null if the specified
79: * transaction doesn't exist.
80: */
81: public Transaction find(long transId) {
82: return (Transaction) map.get(transId);
83: }
84:
85: /**
86: * Return this transaction to the pool
87: */
88: public void release(Transaction t) {
89: map.remove(t.transactionId);
90: t.wait = null;
91: super.release(t);
92: }
93: }
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