Remove opentracing from dd-trace-api

dd-java-agent/instrumentation/java-concurrent/src/main/java/datadog/trace/instrumentation/java/concurrent/ExecutorInstrumentation.java

@@ -237,11 +237,11 @@ public final class ExecutorInstrumentation extends Instrumenter.Configurable {
 
     @Override
     public void run() {
-      final Scope scope = continuation.activate();
+      final ContextPropagator context = continuation.activate();
       try {
         delegatee.run();
       } finally {
-        scope.close();
+        context.close();
       }
     }
   }
@@ -257,11 +257,11 @@ public final class ExecutorInstrumentation extends Instrumenter.Configurable {
 
     @Override
     public T call() throws Exception {
-      final Scope scope = continuation.activate();
+      final ContextPropagator context = continuation.activate();
       try {
         return delegatee.call();
       } finally {
-        scope.close();
+        context.close();
       }
     }
   }

dd-trace-api/dd-trace-api.gradle

@@ -5,6 +5,5 @@ apply from: "${rootDir}/gradle/jacoco.gradle"
 description = 'dd-trace-api'
 dependencies {
   compile deps.slf4j
-  compile deps.opentracing
   testCompile deps.junit
 }

dd-trace-api/src/main/java/datadog/trace/context/ContextPropagator.java

@@ -1,21 +1,25 @@
 package datadog.trace.context;
 
-import io.opentracing.Scope;
-
 /** An object when can propagate a datadog trace across multiple threads. */
 public interface ContextPropagator {
   /**
    * Prevent the trace attached to this ContextPropagator from reporting until the returned
    * Continuation finishes.
+   *
+   * <p>Should be called on the parent thread.
    */
-  public Continuation capture(boolean finishOnClose);
+  Continuation capture(boolean finishOnClose);
+
+  /** Close the activated context and allow any underlying spans to finish. */
+  void close();
 
   /** Used to pass async context between workers. */
-  public static interface Continuation {
+  interface Continuation {
     /**
-     * Activate the continuation. When the returned scope is closed, the continuation will no longer
-     * prevent the trace from reporting.
+     * Activate the continuation.
+     *
+     * <p>Should be called on the child thread.
      */
-    public Scope activate();
+    ContextPropagator activate();
   }
 }

dd-trace-ot/src/main/java/datadog/opentracing/scopemanager/ContinuableScope.java

@@ -86,7 +86,7 @@ public class ContinuableScope implements Scope, ContextPropagator {
       }
     }
 
-    public Scope activate() {
+    public ClosingScope activate() {
       if (used.compareAndSet(false, true)) {
         for (final ScopeContext context : scopeManager.scopeContexts) {
           if (context.inContext()) {
@@ -97,7 +97,7 @@ public class ContinuableScope implements Scope, ContextPropagator {
             new ContinuableScope(scopeManager, refCount, wrapped, finishSpanOnClose));
       } else {
         log.debug("Reusing a continuation not allowed.  Returning no-op scope.");
-        return NoopScopeManager.NoopScope.INSTANCE;
+        return new ClosingScope(NoopScopeManager.NoopScope.INSTANCE);
       }
     }
 
@@ -109,17 +109,30 @@ public class ContinuableScope implements Scope, ContextPropagator {
       }
     }
 
-    private class ClosingScope implements Scope {
+    private class ClosingScope implements Scope, ContextPropagator {
       private final Scope wrappedScope;
 
       private ClosingScope(final Scope wrappedScope) {
         this.wrappedScope = wrappedScope;
       }
 
+      @Override
+      public Continuation capture(boolean finishOnClose) {
+        if (wrappedScope instanceof ContextPropagator) {
+          return ((ContextPropagator) wrappedScope).capture(finishOnClose);
+        } else {
+          log.debug(
+              "{} Failed to capture. ClosingScope does not wrap a ContextPropagator: {}.",
+              this,
+              wrappedScope);
+          return null;
+        }
+      }
+
       @Override
       public void close() {
         wrappedScope.close();
-        Continuation.this.close();
+        ContinuableScope.Continuation.this.close();
       }
 
       @Override