-
Notifications
You must be signed in to change notification settings - Fork 23
/
ThreadContextController.java
74 lines (73 loc) · 2.86 KB
/
ThreadContextController.java
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
/*
* Copyright (c) 2018,2019 Contributors to the Eclipse Foundation
*
* See the NOTICE file(s) distributed with this work for additional
* information regarding copyright ownership.
*
* 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.eclipse.microprofile.context.spi;
/**
* <p>Represents context that is applied to a particular thread, along with any
* state that is associated with it or that is necessary for restoring the
* previous context afterward.</p>
*
* <p>When the context is no longer needed on the thread, the
* <code>ManagedExecutor</code> or <code>ThreadContext</code> must invoke the
* <code>endContext</code> method.</p>
*/
@FunctionalInterface
public interface ThreadContextController {
/**
* <p>Invoked by the <code>ManagedExecutor</code> or
* <code>ThreadContext</code> to remove the thread context managed by
* this <code>ThreadContextController</code> instance and restore the previous
* context that was on the thread before the <code>ThreadContextController</code>
* applied the context to the thread. The <code>ManagedExecutor</code> or
* <code>ThreadContext</code> must invoke the <code>endContext</code> method exactly
* once for each <code>ThreadContextController</code> instance that it creates.</p>
*
* <p>Typically, patterns such as the following will be observed:</p>
* <pre><code>
* controllerA1 = contextSnapshotA.begin();
* controllerB1 = contextSnapshotB.begin();
* controllerC1 = contextSnapshotC.begin();
* ...
* controllerC1.endContext();
* controllerB1.endContext();
* controllerA1.endContext();
* </code></pre>
*
* <p>However, more advanced sequences such as the following are also valid:</p>
* <pre><code>
* controllerA1 = contextSnapshotA.begin();
* controllerB1 = contextSnapshotB.begin();
* ...
* controllerC1 = contextSnapshotC.begin();
* ...
* controllerC1.endContext();
* ...
* controllerB2 = contextSnapshotB.begin();
* controllerC2 = contextSnapshotC.begin();
* ...
* controllerC2.endContext();
* controllerB2.endContext();
* ...
* controllerB1.endContext();
* controllerA1.endContext();
* </code></pre>
*
* @throws IllegalStateException if invoked more than once on the same instance.
*/
void endContext() throws IllegalStateException;
}