blob: 8936bbbbf26c30ce1fc96039af0d6d8b67a8d115 (
plain)
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
|
/*
* Copyright 2017, OpenCensus Authors
*
* 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 io.opencensus.tags.unsafe;
import io.grpc.Context;
import io.opencensus.tags.Tag;
import io.opencensus.tags.TagContext;
import java.util.Collections;
import java.util.Iterator;
import javax.annotation.concurrent.Immutable;
/**
* Utility methods for accessing the {@link TagContext} contained in the {@link io.grpc.Context}.
*
* <p>Most code should interact with the current context via the public APIs in {@link
* io.opencensus.tags.TagContext} and avoid accessing {@link #TAG_CONTEXT_KEY} directly.
*
* @since 0.8
*/
public final class ContextUtils {
private static final TagContext EMPTY_TAG_CONTEXT = new EmptyTagContext();
private ContextUtils() {}
/**
* The {@link io.grpc.Context.Key} used to interact with the {@code TagContext} contained in the
* {@link io.grpc.Context}.
*
* @since 0.8
*/
public static final Context.Key<TagContext> TAG_CONTEXT_KEY =
Context.keyWithDefault("opencensus-tag-context-key", EMPTY_TAG_CONTEXT);
@Immutable
private static final class EmptyTagContext extends TagContext {
@Override
protected Iterator<Tag> getIterator() {
return Collections.<Tag>emptySet().iterator();
}
}
}
|
