Remove MessageEvent and make Event extensible.

api/src/main/java/openconsensus/trace/BlankSpan.java

@@ -19,8 +19,6 @@
 import java.util.Map;
 import javax.annotation.concurrent.Immutable;
 import openconsensus.internal.Utils;
-import openconsensus.trace.data.Event;
-import openconsensus.trace.data.MessageEvent;
 
 /**
  * The {@code BlankSpan} is a singleton class, which is the default {@link Span} that is used when
@@ -82,11 +80,6 @@ public void addEvent(Event event) {
     Utils.checkNotNull(event, "event");
   }
 
-  @Override
-  public void addMessageEvent(MessageEvent messageEvent) {
-    Utils.checkNotNull(messageEvent, "messageEvent");
-  }
-
   @Override
   public void addLink(Link link) {
     Utils.checkNotNull(link, "link");

api/src/main/java/openconsensus/trace/data/Event.java → api/src/main/java/openconsensus/trace/Event.java

@@ -14,27 +14,44 @@
  * limitations under the License.
  */
 
-package openconsensus.trace.data;
+package openconsensus.trace;
 
 import com.google.auto.value.AutoValue;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import javax.annotation.concurrent.Immutable;
 import openconsensus.internal.Utils;
-import openconsensus.trace.AttributeValue;
 
 /**
  * A text annotation with a set of attributes.
  *
  * @since 0.1.0
  */
 @Immutable
-@AutoValue
 public abstract class Event {
   private static final Map<String, AttributeValue> EMPTY_ATTRIBUTES =
       Collections.unmodifiableMap(Collections.<String, AttributeValue>emptyMap());
 
+  /**
+   * Return the name of the {@code Event}.
+   *
+   * @return the name of the {@code Event}.
+   * @since 0.1.0
+   */
+  public abstract String getName();
+
+  /**
+   * Return the attributes of the {@code Event}.
+   *
+   * @return the attributes of the {@code Event}.
+   * @since 0.1.0
+   */
+  public abstract Map<String, AttributeValue> getAttributes();
+
+  /** Protected constructor to allow subclassing this class. */
+  protected Event() {}
+
   /**
    * Returns a new {@code Event} with the given name.
    *
@@ -43,8 +60,8 @@ public abstract class Event {
    * @throws NullPointerException if {@code name} is {@code null}.
    * @since 0.1.0
    */
-  public static Event fromName(String name) {
-    return new AutoValue_Event(name, EMPTY_ATTRIBUTES);
+  public static Event create(String name) {
+    return new AutoValue_Event_ImmutableEvent(name, EMPTY_ATTRIBUTES);
   }
 
   /**
@@ -56,28 +73,20 @@ public static Event fromName(String name) {
    * @throws NullPointerException if {@code name} or {@code attributes} are {@code null}.
    * @since 0.1.0
    */
-  public static Event fromNameAndAttributes(String name, Map<String, AttributeValue> attributes) {
-    return new AutoValue_Event(
+  public static Event create(String name, Map<String, AttributeValue> attributes) {
+    return new AutoValue_Event_ImmutableEvent(
         name,
-        Collections.unmodifiableMap(
-            new HashMap<String, AttributeValue>(Utils.checkNotNull(attributes, "attributes"))));
+        Collections.unmodifiableMap(new HashMap<>(Utils.checkNotNull(attributes, "attributes"))));
   }
 
   /**
-   * Return the name of the {@code Event}.
+   * A text annotation with a set of attributes.
    *
-   * @return the name of the {@code Event}.
    * @since 0.1.0
    */
-  public abstract String getName();
-
-  /**
-   * Return the attributes of the {@code Event}.
-   *
-   * @return the attributes of the {@code Event}.
-   * @since 0.1.0
-   */
-  public abstract Map<String, AttributeValue> getAttributes();
-
-  Event() {}
+  @Immutable
+  @AutoValue
+  abstract static class ImmutableEvent extends Event {
+    ImmutableEvent() {}
+  }
 }

api/src/main/java/openconsensus/trace/Span.java

@@ -17,8 +17,6 @@
 package openconsensus.trace;
 
 import java.util.Map;
-import openconsensus.trace.data.Event;
-import openconsensus.trace.data.MessageEvent;
 
 /**
  * An abstract class that represents a span. It has an associated {@link SpanContext}.
@@ -106,19 +104,6 @@ public abstract class Span {
    */
   public abstract void addEvent(Event event);
 
-  /**
-   * Adds a MessageEvent to the {@code Span}.
-   *
-   * <p>This function can be used by higher level applications to record messaging event.
-   *
-   * <p>This method should always be overridden by users whose API versions are larger or equal to
-   * {@code 0.12}.
-   *
-   * @param messageEvent the message to add.
-   * @since 0.1.0
-   */
-  public abstract void addMessageEvent(MessageEvent messageEvent);
-
   /**
    * Adds a {@link Link} to the {@code Span}.
    *

api/src/main/java/openconsensus/trace/data/SpanData.java

@@ -27,6 +27,7 @@
 import openconsensus.common.Timestamp;
 import openconsensus.internal.Utils;
 import openconsensus.trace.AttributeValue;
+import openconsensus.trace.Event;
 import openconsensus.trace.Link;
 import openconsensus.trace.Span;
 import openconsensus.trace.Span.Kind;
@@ -54,8 +55,6 @@ public abstract class SpanData {
    * @param startTimestamp the start {@code Timestamp} of the {@code Span}.
    * @param attributes the attributes associated with the {@code Span}.
    * @param events the events associated with the {@code Span}.
-   * @param messageEvents the message events (or network events for backward compatibility)
-   *     associated with the {@code Span}.
    * @param links the links associated with the {@code Span}.
    * @param childSpanCount the number of child spans that were generated while the span was active.
    * @param status the {@code Status} of the {@code Span}. {@code null} if the {@code Span} is still
@@ -73,12 +72,11 @@ public static SpanData create(
       Timestamp startTimestamp,
       Attributes attributes,
       TimedEvents<Event> events,
-      TimedEvents<MessageEvent> messageEvents,
       Links links,
       @Nullable Integer childSpanCount,
       @Nullable Status status,
       @Nullable Timestamp endTimestamp) {
-    Utils.checkNotNull(messageEvents, "messageEvents");
+    Utils.checkNotNull(events, "events");
     return new AutoValue_SpanData(
         context,
         parentSpanId,
@@ -87,7 +85,6 @@ public static SpanData create(
         startTimestamp,
         attributes,
         events,
-        messageEvents,
         links,
         childSpanCount,
         status,
@@ -151,14 +148,6 @@ public static SpanData create(
    */
   public abstract TimedEvents<Event> getEvents();
 
-  /**
-   * Returns message events recorded for this {@code Span}.
-   *
-   * @return message events recorded for this {@code Span}.
-   * @since 0.1.0
-   */
-  public abstract TimedEvents<MessageEvent> getMessageEvents();
-
   /**
    * Returns links recorded for this {@code Span}.
    *

build.gradle

@@ -38,7 +38,7 @@ subprojects {
     apply plugin: 'com.github.sherter.google-java-format'
     apply plugin: "net.ltgt.errorprone"
 
-    group = "io.openconsensus"
+    group = "openconsensus"
     version = "0.1.0-SNAPSHOT" // CURRENT_VERSION
 
     sourceCompatibility = 1.7

contrib/README.md

@@ -0,0 +1,6 @@
+OpenCensus API
+======================================================
+
+* Java 7 and Android 14 compatible.
+* The abstract classes in this directory can be subclassed to create alternative
+  implementations of the OpenCensus library.

contrib/build.gradle

@@ -0,0 +1,15 @@
+description = 'OpenConsensus Contrib'
+
+dependencies {
+    compile project(':openconsensus-api')
+
+    compileOnly libraries.auto_value
+
+    signature "org.codehaus.mojo.signature:java17:1.0@signature"
+    signature "net.sf.androidscents.signature:android-api-level-14:4.0_r4@signature"
+}
+
+javadoc {
+    exclude 'io/opencensus/internal/**'
+    exclude 'io/opencensus/trace/internal/**'
+}