Implement TimedEvent in SDK. (#354)

* Implement Event in SDK.

* Make EventSdk package-private.

* EventSdk -> TimedEvent.

sdk/src/main/java/io/opentelemetry/sdk/trace/TimedEvent.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright 2019, OpenTelemetry 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.opentelemetry.sdk.trace;
+
+import com.google.auto.value.AutoValue;
+import io.opentelemetry.trace.AttributeValue;
+import io.opentelemetry.trace.Event;
+import java.util.Collections;
+import java.util.Map;
+import javax.annotation.concurrent.Immutable;
+
+/** Timed event that uses nanoTime to represent the Timestamp. */
+@Immutable
+abstract class TimedEvent {
+
+  private static final Map<String, AttributeValue> EMPTY_ATTRIBUTES =
+      Collections.unmodifiableMap(Collections.<String, AttributeValue>emptyMap());
+
+  abstract long getNanotime();
+
+  abstract String getName();
+
+  abstract Map<String, AttributeValue> getAttributes();
+
+  TimedEvent() {}
+
+  /**
+   * Creates an {@link TimedEvent} with the given time, name and empty attributes.
+   *
+   * @param nanoTime time in nanos.
+   * @param name the name of this {@code TimedEvent}.
+   * @return an {@code TimedEvent}.
+   */
+  static TimedEvent create(long nanoTime, String name) {
+    return create(nanoTime, name, EMPTY_ATTRIBUTES);
+  }
+
+  /**
+   * Creates an {@link TimedEvent} with the given time, name and attributes.
+   *
+   * @param nanoTime time in nanos.
+   * @param name the name of this {@code TimedEvent}.
+   * @param attributes the attributes of this {@code TimedEvent}.
+   * @return an {@code TimedEvent}.
+   */
+  static TimedEvent create(long nanoTime, String name, Map<String, AttributeValue> attributes) {
+    return new AutoValue_TimedEvent_RawTimedEvent(nanoTime, name, attributes);
+  }
+
+  /**
+   * Creates an {@link TimedEvent} with the given time and event.
+   *
+   * @param nanoTime time in nanos.
+   * @param event the event.
+   * @return an {@code TimedEvent}.
+   */
+  static TimedEvent create(long nanoTime, Event event) {
+    return new AutoValue_TimedEvent_TimedEventWithEvent(nanoTime, event);
+  }
+
+  @AutoValue
+  abstract static class TimedEventWithEvent extends TimedEvent {
+    abstract Event getEvent();
+
+    @Override
+    String getName() {
+      return getEvent().getName();
+    }
+
+    @Override
+    Map<String, AttributeValue> getAttributes() {
+      return getEvent().getAttributes();
+    }
+  }
+
+  @AutoValue
+  abstract static class RawTimedEvent extends TimedEvent {}
+}

sdk/src/test/java/io/opentelemetry/sdk/trace/TimedEventTest.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2019, OpenTelemetry 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.opentelemetry.sdk.trace;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import io.opentelemetry.trace.AttributeValue;
+import io.opentelemetry.trace.Event;
+import java.util.Collections;
+import java.util.Map;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link TimedEvent}. */
+@RunWith(JUnit4.class)
+public class TimedEventTest {
+
+  private static final String NAME = "event";
+  private static final String NAME_2 = "event2";
+  private static final Map<String, AttributeValue> ATTRIBUTES =
+      Collections.singletonMap("attribute", AttributeValue.stringAttributeValue("value"));
+  private static final Map<String, AttributeValue> ATTRIBUTES_2 =
+      Collections.singletonMap("attribute2", AttributeValue.stringAttributeValue("value2"));
+  private static final Event EVENT =
+      new Event() {
+        @Override
+        public String getName() {
+          return NAME_2;
+        }
+
+        @Override
+        public Map<String, AttributeValue> getAttributes() {
+          return ATTRIBUTES_2;
+        }
+      };
+
+  @Test
+  public void rawTimedEventWithName() {
+    TimedEvent event = TimedEvent.create(1000, NAME);
+    assertThat(event.getNanotime()).isEqualTo(1000);
+    assertThat(event.getName()).isEqualTo(NAME);
+    assertThat(event.getAttributes()).isEmpty();
+  }
+
+  @Test
+  public void rawTimedEventWithNameAndAttributes() {
+    TimedEvent event = TimedEvent.create(2000, NAME, ATTRIBUTES);
+    assertThat(event.getNanotime()).isEqualTo(2000);
+    assertThat(event.getName()).isEqualTo(NAME);
+    assertThat(event.getAttributes()).isEqualTo(ATTRIBUTES);
+  }
+
+  @Test
+  public void timedEventWithEvent() {
+    TimedEvent event = TimedEvent.create(3000, EVENT);
+    assertThat(event.getNanotime()).isEqualTo(3000);
+    assertThat(event.getName()).isEqualTo(NAME_2);
+    assertThat(event.getAttributes()).isEqualTo(ATTRIBUTES_2);
+  }
+}