forked from census-instrumentation/opencensus-java
/
Tracing.java
141 lines (130 loc) · 4.33 KB
/
Tracing.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
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
/*
* Copyright 2016-17, 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.trace;
import io.opencensus.common.Clock;
import io.opencensus.internal.DefaultVisibilityForTesting;
import io.opencensus.internal.Provider;
import io.opencensus.trace.config.TraceConfig;
import io.opencensus.trace.export.ExportComponent;
import io.opencensus.trace.propagation.PropagationComponent;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.Nullable;
/**
* Class that manages a global instance of the {@link TraceComponent}.
*
* @since 0.5
*/
public final class Tracing {
private static final Logger logger = Logger.getLogger(Tracing.class.getName());
private static final TraceComponent traceComponent =
loadTraceComponent(TraceComponent.class.getClassLoader());
/**
* Returns the global {@link Tracer}.
*
* @return the global {@code Tracer}.
* @since 0.5
*/
public static Tracer getTracer() {
return traceComponent.getTracer();
}
/**
* Returns the global {@link PropagationComponent}.
*
* @return the global {@code PropagationComponent}.
* @since 0.5
*/
public static PropagationComponent getPropagationComponent() {
return traceComponent.getPropagationComponent();
}
/**
* Returns the global {@link Clock}.
*
* @return the global {@code Clock}.
* @since 0.5
*/
public static Clock getClock() {
return traceComponent.getClock();
}
/**
* Returns the global {@link ExportComponent}.
*
* @return the global {@code ExportComponent}.
* @since 0.5
*/
public static ExportComponent getExportComponent() {
return traceComponent.getExportComponent();
}
/**
* Returns the global {@link TraceConfig}.
*
* @return the global {@code TraceConfig}.
* @since 0.5
*/
public static TraceConfig getTraceConfig() {
return traceComponent.getTraceConfig();
}
// Any provider that may be used for TraceComponent can be added here.
@DefaultVisibilityForTesting
static TraceComponent loadTraceComponent(@Nullable ClassLoader classLoader) {
try {
// Call Class.forName with literal string name of the class to help shading tools.
return Provider.createInstance(
Class.forName(
"io.opentelemetry.opencensusshim.OpenTelemetryTraceComponentImpl",
/*initialize=*/ true,
classLoader),
TraceComponent.class);
} catch (ClassNotFoundException e) {
logger.log(
Level.FINE,
"Couldn't load full implementation for OpenTelemetry TraceComponent, now trying to load "
+ "original implementation.",
e);
}
try {
// Call Class.forName with literal string name of the class to help shading tools.
return Provider.createInstance(
Class.forName(
"io.opencensus.impl.trace.TraceComponentImpl", /*initialize=*/ true, classLoader),
TraceComponent.class);
} catch (ClassNotFoundException e) {
logger.log(
Level.FINE,
"Couldn't load full implementation for TraceComponent, now trying to load lite "
+ "implementation.",
e);
}
try {
// Call Class.forName with literal string name of the class to help shading tools.
return Provider.createInstance(
Class.forName(
"io.opencensus.impllite.trace.TraceComponentImplLite",
/*initialize=*/ true,
classLoader),
TraceComponent.class);
} catch (ClassNotFoundException e) {
logger.log(
Level.FINE,
"Couldn't load lite implementation for TraceComponent, now using "
+ "default implementation for TraceComponent.",
e);
}
return TraceComponent.newNoopTraceComponent();
}
// No instance of this class.
private Tracing() {}
}