com.google.cloud.trace.jdbc.ThreadLocalTracerStore Maven / Gradle / Ivy
// Copyright 2016 Google Inc. All rights reserved.
//
// 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 com.google.cloud.trace.jdbc;
import com.google.cloud.trace.Tracer;
import com.google.common.base.Optional;
/**
* Thread-local context holding the current thread's {@link Tracer} (if any).
*
* This context is used for passing the {@code Tracer} to other methods in cases where
* there is no way to pass the {@code Tracer} as a parameter.
*
* TODO: Replace this with the upcoming mechanism in the Cloud Trace for Java SDK.
*/
public final class ThreadLocalTracerStore {
private ThreadLocalTracerStore() {}
/** Holds the current thread's {@link Tracer} (if any). */
private static final ThreadLocal perThreadTracer = new ThreadLocal<>();
/** Returns the current thread's {@link Tracer}. */
public static Optional getCurrent() {
return Optional.fromNullable(perThreadTracer.get());
}
/** Sets the {@link Tracer} associated with the current thread. */
public static void setCurrent(Tracer tracer) {
perThreadTracer.set(tracer);
}
/** Removes the current thread's {@link Tracer}. */
public static void remove() {
perThreadTracer.remove();
}
}