Repository navigation
Expand file tree
/
Copy pathTxMaker.java
More file actions
117 lines (103 loc) · 3.46 KB
/
Copy pathTxMaker.java
File metadata and controls
117 lines (103 loc) · 3.46 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
/*
* Copyright (c) 2012 Jan Kotek
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.mapdb;
import java.io.Closeable;
import java.util.concurrent.ScheduledExecutorService;
/**
* Transaction factory
*
* @author Jan Kotek
*/
public class TxMaker implements Closeable {
private final boolean strictDBGet;
protected ScheduledExecutorService executor;
/** parent engine under which modifications are stored */
protected Engine engine;
protected final Fun.Function1<Class, String> serializerClassLoader;
public TxMaker(Engine engine) {
this(engine,false, null, null);
}
public TxMaker(
Engine engine,
boolean strictDBGet,
ScheduledExecutorService executor,
Fun.Function1<Class, String> serializerClassLoader) {
if(engine==null)
throw new IllegalArgumentException();
if(!engine.canSnapshot())
throw new IllegalArgumentException("Snapshot must be enabled for TxMaker");
if(engine.isReadOnly())
throw new IllegalArgumentException("TxMaker can not be used with read-only Engine");
this.engine = engine;
this.strictDBGet = strictDBGet;
this.executor = executor;
this.serializerClassLoader = serializerClassLoader;
}
public DB makeTx(){
Engine snapshot = engine.snapshot();
if(snapshot.isReadOnly())
throw new AssertionError();
// if(txSnapshotsEnabled)
// snapshot = new TxEngine(snapshot,false); //TODO
return new DB(snapshot,strictDBGet,false,executor, true, null, 0, null, null, serializerClassLoader);
}
public void close() {
engine.close();
engine = null;
}
/**
* Executes given block withing single transaction.
* If block throws {@code TxRollbackException} execution is repeated until it does not fail.
*
* @param txBlock
*/
public void execute(TxBlock txBlock) {
for(;;){
DB tx = makeTx();
try{
txBlock.tx(tx);
if(!tx.isClosed())
tx.commit();
return;
}catch(TxRollbackException e){
//failed, so try again
if(!tx.isClosed()) tx.close();
}
}
}
/**
* Executes given block withing single transaction.
* If block throws {@code TxRollbackException} execution is repeated until it does not fail.
*
* This method returns result returned by txBlock.
*
* @param txBlock
*/
public <A> A execute(Fun.Function1<A, DB> txBlock) {
for(;;){
DB tx = makeTx();
try{
A a = txBlock.run(tx);
if(!tx.isClosed())
tx.commit();
return a;
}catch(TxRollbackException e){
//failed, so try again
if(!tx.isClosed()) tx.close();
}
}
}
}