diff options
Diffstat (limited to 'api/src/main/java/io/opencensus/trace/Tracing.java')
-rw-r--r-- | api/src/main/java/io/opencensus/trace/Tracing.java | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/api/src/main/java/io/opencensus/trace/Tracing.java b/api/src/main/java/io/opencensus/trace/Tracing.java new file mode 100644 index 00000000..f55cd775 --- /dev/null +++ b/api/src/main/java/io/opencensus/trace/Tracing.java @@ -0,0 +1,125 @@ +/* + * 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.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() {} +} |