1 files changed, 95 insertions, 0 deletions
diff --git a/api/src/main/java/io/opencensus/trace/export/ExportComponent.java b/api/src/main/java/io/opencensus/trace/export/ExportComponent.java
new file mode 100644
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+++ b/api/src/main/java/io/opencensus/trace/export/ExportComponent.java
@@ -0,0 +1,95 @@
+/*
+ * 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.trace.export;
+
+import io.opencensus.trace.TraceOptions;
+
+/**
+ * Class that holds the implementation instances for {@link SpanExporter}, {@link RunningSpanStore}
+ * and {@link SampledSpanStore}.
+ *
+ * <p>Unless otherwise noted all methods (on component) results are cacheable.
+ *
+ * @since 0.5
+ */
+public abstract class ExportComponent {
+
+  /**
+   * Returns the no-op implementation of the {@code ExportComponent}.
+   *
+   * @return the no-op implementation of the {@code ExportComponent}.
+   * @since 0.5
+   */
+  public static ExportComponent newNoopExportComponent() {
+    return new NoopExportComponent();
+  }
+
+  /**
+   * Returns the {@link SpanExporter} which can be used to register handlers to export all the spans
+   * that are part of a distributed sampled trace (see {@link TraceOptions#isSampled()}).
+   *
+   * @return the implementation of the {@code SpanExporter} or no-op if no implementation linked in
+   *     the binary.
+   * @since 0.5
+   */
+  public abstract SpanExporter getSpanExporter();
+
+  /**
+   * Returns the {@link RunningSpanStore} that can be used to get useful debugging information about
+   * all the current active spans.
+   *
+   * @return the {@code RunningSpanStore}.
+   * @since 0.5
+   */
+  public abstract RunningSpanStore getRunningSpanStore();
+
+  /**
+   * Returns the {@link SampledSpanStore} that can be used to get useful debugging information, such
+   * as latency based sampled spans, error based sampled spans.
+   *
+   * @return the {@code SampledSpanStore}.
+   * @since 0.5
+   */
+  public abstract SampledSpanStore getSampledSpanStore();
+
+  /**
+   * Will shutdown this ExportComponent after flushing any pending spans.
+   *
+   * @since 0.14
+   */
+  public void shutdown() {}
+
+  private static final class NoopExportComponent extends ExportComponent {
+    private final SampledSpanStore noopSampledSpanStore =
+        SampledSpanStore.newNoopSampledSpanStore();
+
+    @Override
+    public SpanExporter getSpanExporter() {
+      return SpanExporter.getNoopSpanExporter();
+    }
+
+    @Override
+    public RunningSpanStore getRunningSpanStore() {
+      return RunningSpanStore.getNoopRunningSpanStore();
+    }
+
+    @Override
+    public SampledSpanStore getSampledSpanStore() {
+      return noopSampledSpanStore;
+    }
+  }
+}