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
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
|
/*
* Copyright (c) 2010-2012, 2014, 2016 Eike Stepper (Loehne, Germany) and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Eike Stepper - initial API and implementation
* Simon McDuff - bug 201266
* Simon McDuff - bug 233314
* Simon McDuff - bug 247143
*/
package org.eclipse.emf.cdo.transaction;
import org.eclipse.emf.cdo.CDOObject;
import org.eclipse.emf.cdo.common.revision.delta.CDOFeatureDelta;
import org.eclipse.emf.cdo.view.CDOView;
/**
* A call-back interface that is called by a {@link CDOTransaction transaction} before {@link CDOObject objects} are
* attached, modified or detached.
*
* @see CDOPostEventTransactionHandler
* @author Eike Stepper
* @since 4.0
*/
public interface CDOTransactionHandler1 extends CDOTransactionHandlerBase
{
/**
* Called by a <code>CDOTransaction</code> <b>before</b> an object is added. The implementor of this method is allowed
* to throw an unchecked exception that will propagate up to the operation that is about to add the object (thereby
* preventing the operation from successful completion).
* <p>
* <b>Note:</b> Implementors <b>must not</b> start threads which access the {@link CDOView view} and wait for their
* completion since deadlocks can result. The following example causes a deadlock:<br>
*
* <pre>
* getDisplay().syncExec(new Runnable()
* {
* public void run()
* {
* try
* {
* cdoObject.getName();
* }
* catch (Exception ignore)
* {
* }
* }
* });
* </pre>
*
* If you need to synchronously execute threads which access the {@link CDOView view} you should use
* {@link CDOAsyncTransactionHandler}.
*/
public void attachingObject(CDOTransaction transaction, CDOObject object);
/**
* Called by a <code>CDOTransaction</code> <b>before</b> an object is detached. The implementor of this method is
* allowed to throw an unchecked exception that will propagate up to the operation that is about to remove the object
* (thereby preventing the operation from completing successfully).
* <p>
* <b>Note:</b> Implementors <b>must not</b> start threads which access the {@link CDOView view} and wait for their
* completion since deadlocks can result. The following example causes a deadlock:<br>
*
* <pre>
* getDisplay().syncExec(new Runnable()
* {
* public void run()
* {
* try
* {
* cdoObject.getName();
* }
* catch (Exception ignore)
* {
* }
* }
* });
* </pre>
*
* If you need to synchronously execute threads which access the {@link CDOView view} you should use
* {@link CDOAsyncTransactionHandler}.
*/
public void detachingObject(CDOTransaction transaction, CDOObject object);
/**
* Called by a <code>CDOTransaction</code> <b>before</b> an object is modified. The implementor of this method is
* allowed to throw an unchecked exception that will propagate up to the operation that is about to modify the object
* (thereby preventing the operation from completing successfully).
* <p>
* <b>Note:</b> Implementors <b>must not</b> start threads which access the {@link CDOView view} and wait for their
* completion since deadlocks can result. The following example causes a deadlock:<br>
*
* <pre>
* getDisplay().syncExec(new Runnable()
* {
* public void run()
* {
* try
* {
* cdoObject.getName();
* }
* catch (Exception ignore)
* {
* }
* }
* });
* </pre>
*
* If you need to synchronously execute threads which access the {@link CDOView view} you should use
* {@link CDOAsyncTransactionHandler}.
*/
public void modifyingObject(CDOTransaction transaction, CDOObject object, CDOFeatureDelta featureDelta);
/**
* A call-back interface that is called by a {@link CDOTransaction transaction} before {@link CDOObject objects} are
* attached, modified, undone or detached.
*
* @author Eike Stepper
* @since 4.6
*/
public interface WithUndo extends CDOTransactionHandler1
{
/**
* Called by a <code>CDOTransaction</code> <b>before</b> an object is modified. The implementor of this method is
* allowed to throw an unchecked exception that will propagate up to the operation that is about to modify the object
* (thereby preventing the operation from completing successfully).
* <p>
* <b>Note:</b> Implementors <b>must not</b> start threads which access the {@link CDOView view} and wait for their
* completion since deadlocks can result. The following example causes a deadlock:<br>
*
* <pre>
* getDisplay().syncExec(new Runnable()
* {
* public void run()
* {
* try
* {
* cdoObject.getName();
* }
* catch (Exception ignore)
* {
* }
* }
* });
* </pre>
*
* If you need to synchronously execute threads which access the {@link CDOView view} you should use
* {@link CDOAsyncTransactionHandler}.
*/
public void undoingObject(CDOTransaction transaction, CDOObject object, CDOFeatureDelta featureDelta);
}
}
|
