1 files changed, 90 insertions, 0 deletions
diff --git a/impl_core/src/main/java/io/opencensus/implcore/trace/TraceComponentImplBase.java b/impl_core/src/main/java/io/opencensus/implcore/trace/TraceComponentImplBase.java
new file mode 100644
index 00000000..c1432432
--- /dev/null
+++ b/impl_core/src/main/java/io/opencensus/implcore/trace/TraceComponentImplBase.java
@@ -0,0 +1,90 @@
+/*
+ * 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.implcore.trace;
+
+import io.opencensus.common.Clock;
+import io.opencensus.implcore.internal.EventQueue;
+import io.opencensus.implcore.internal.SimpleEventQueue;
+import io.opencensus.implcore.trace.RecordEventsSpanImpl.StartEndHandler;
+import io.opencensus.implcore.trace.config.TraceConfigImpl;
+import io.opencensus.implcore.trace.export.ExportComponentImpl;
+import io.opencensus.implcore.trace.internal.RandomHandler;
+import io.opencensus.implcore.trace.propagation.PropagationComponentImpl;
+import io.opencensus.trace.TraceComponent;
+import io.opencensus.trace.Tracer;
+import io.opencensus.trace.config.TraceConfig;
+import io.opencensus.trace.export.ExportComponent;
+import io.opencensus.trace.propagation.PropagationComponent;
+
+/**
+ * Helper class to allow sharing the code for all the {@link TraceComponent} implementations. This
+ * class cannot use inheritance because in version 0.5.* the constructor of the {@code
+ * TraceComponent} is package protected.
+ *
+ * <p>This can be changed back to inheritance when version 0.5.* is no longer supported.
+ */
+public final class TraceComponentImplBase {
+  private final ExportComponentImpl exportComponent;
+  private final PropagationComponent propagationComponent = new PropagationComponentImpl();
+  private final Clock clock;
+  private final TraceConfig traceConfig = new TraceConfigImpl();
+  private final Tracer tracer;
+
+  /**
+   * Creates a new {@code TraceComponentImplBase}.
+   *
+   * @param clock the clock to use throughout tracing.
+   * @param randomHandler the random number generator for generating trace and span IDs.
+   * @param eventQueue the queue implementation.
+   */
+  public TraceComponentImplBase(Clock clock, RandomHandler randomHandler, EventQueue eventQueue) {
+    this.clock = clock;
+    // TODO(bdrutu): Add a config/argument for supportInProcessStores.
+    if (eventQueue instanceof SimpleEventQueue) {
+      exportComponent = ExportComponentImpl.createWithoutInProcessStores(eventQueue);
+    } else {
+      exportComponent = ExportComponentImpl.createWithInProcessStores(eventQueue);
+    }
+    StartEndHandler startEndHandler =
+        new StartEndHandlerImpl(
+            exportComponent.getSpanExporter(),
+            exportComponent.getRunningSpanStore(),
+            exportComponent.getSampledSpanStore(),
+            eventQueue);
+    tracer = new TracerImpl(randomHandler, startEndHandler, clock, traceConfig);
+  }
+
+  public Tracer getTracer() {
+    return tracer;
+  }
+
+  public PropagationComponent getPropagationComponent() {
+    return propagationComponent;
+  }
+
+  public final Clock getClock() {
+    return clock;
+  }
+
+  public ExportComponent getExportComponent() {
+    return exportComponent;
+  }
+
+  public TraceConfig getTraceConfig() {
+    return traceConfig;
+  }
+}