core: ManagedChannel should not depend on internal (#3898)

core/src/main/java/io/grpc/ManagedChannel.java

@@ -16,8 +16,6 @@
 
 package io.grpc;
 
-import com.google.common.util.concurrent.ListenableFuture;
-import com.google.common.util.concurrent.SettableFuture;
 import java.util.concurrent.TimeUnit;
 import javax.annotation.concurrent.ThreadSafe;
 
@@ -25,10 +23,7 @@ import javax.annotation.concurrent.ThreadSafe;
  * A {@link Channel} that provides lifecycle management.
  */
 @ThreadSafe
-public abstract class ManagedChannel
-    extends Channel implements InternalInstrumented<InternalChannelStats> {
-  private final InternalLogId logId = InternalLogId.allocate(getClass().getName());
-
+public abstract class ManagedChannel extends Channel {
   /**
    * Initiates an orderly shutdown in which preexisting calls continue but new calls are immediately
    * cancelled.
@@ -88,14 +83,6 @@ public abstract class ManagedChannel
     throw new UnsupportedOperationException("Not implemented");
   }
 
-  @Internal
-  @Override
-  public ListenableFuture<InternalChannelStats> getStats() {
-    SettableFuture<InternalChannelStats> ret = SettableFuture.create();
-    ret.set(null);
-    return ret;
-  }
-
   /**
    * Registers a one-off callback that will be run if the connectivity state of the channel diverges
    * from the given {@code source}, which is typically what has just been returned by {@link
@@ -127,10 +114,4 @@ public abstract class ManagedChannel
    */
   @ExperimentalApi
   public void resetConnectBackoff() {}
-
-  @Internal
-  @Override
-  public final InternalLogId getLogId() {
-    return logId;
-  }
 }

core/src/main/java/io/grpc/internal/ManagedChannelImpl.java

@@ -41,6 +41,7 @@ import io.grpc.Context;
 import io.grpc.DecompressorRegistry;
 import io.grpc.EquivalentAddressGroup;
 import io.grpc.InternalChannelStats;
+import io.grpc.InternalInstrumented;
 import io.grpc.InternalLogId;
 import io.grpc.LoadBalancer;
 import io.grpc.LoadBalancer.PickResult;
@@ -80,7 +81,8 @@ import javax.annotation.concurrent.ThreadSafe;
 
 /** A communication channel for making outgoing RPCs. */
 @ThreadSafe
-public final class ManagedChannelImpl extends ManagedChannel {
+public final class ManagedChannelImpl
+    extends ManagedChannel implements InternalInstrumented<InternalChannelStats> {
   static final Logger logger = Logger.getLogger(ManagedChannelImpl.class.getName());
 
   // Matching this pattern means the target string is a URI target or at least intended to be one.
@@ -106,6 +108,7 @@ public final class ManagedChannelImpl extends ManagedChannel {
   static final Status SUBCHANNEL_SHUTDOWN_STATUS =
       Status.UNAVAILABLE.withDescription("Subchannel shutdown invoked");
 
+  private final InternalLogId logId = InternalLogId.allocate(getClass().getName());
   private final String target;
   private final NameResolver.Factory nameResolverFactory;
   private final Attributes nameResolverParams;
@@ -272,6 +275,11 @@ public final class ManagedChannelImpl extends ManagedChannel {
     return ret;
   }
 
+  @Override
+  public InternalLogId getLogId() {
+    return logId;
+  }
+
   // Run from channelExecutor
   private class IdleModeTimer implements Runnable {
     // Only mutated from channelExecutor

core/src/main/java/io/grpc/internal/OobChannel.java

@@ -28,6 +28,8 @@ import io.grpc.ConnectivityStateInfo;
 import io.grpc.Context;
 import io.grpc.EquivalentAddressGroup;
 import io.grpc.InternalChannelStats;
+import io.grpc.InternalInstrumented;
+import io.grpc.InternalLogId;
 import io.grpc.LoadBalancer;
 import io.grpc.LoadBalancer.PickResult;
 import io.grpc.LoadBalancer.PickSubchannelArgs;
@@ -51,13 +53,15 @@ import javax.annotation.concurrent.ThreadSafe;
  * to its own RPC needs.
  */
 @ThreadSafe
-final class OobChannel extends ManagedChannel {
+final class OobChannel
+    extends ManagedChannel implements InternalInstrumented<InternalChannelStats> {
   private static final Logger log = Logger.getLogger(OobChannel.class.getName());
 
   private InternalSubchannel subchannel;
   private AbstractSubchannel subchannelImpl;
   private SubchannelPicker subchannelPicker;
 
+  private final InternalLogId logId = InternalLogId.allocate(getClass().getName());
   private final String authority;
   private final DelayedClientTransport delayedTransport;
   private final ObjectPool<? extends Executor> executorPool;
@@ -245,4 +249,9 @@ final class OobChannel extends ManagedChannel {
     ret.set(channelTracer.getStats());
     return ret;
   }
+
+  @Override
+  public InternalLogId getLogId() {
+    return logId;
+  }
 }