all: move Channelz to io.grpc as InternalChannelz (#4797)

This is an API used to coordinate across packages and must live in
`io.grpc`.

Prepending `Internal` makes it easier to detect and hide this class
from public visibility when using certain build tools.

fixes #4796

32 files changed, 123 insertions, 75 deletions

diff --git a/core/src/jmh/java/io/grpc/internal/ChannelzBenchmark.java b/core/src/jmh/java/io/grpc/internal/ChannelzBenchmark.java
index 55afb9c10..8ebe673e2 100644
--- a/core/src/jmh/java/io/grpc/internal/ChannelzBenchmark.java
+++ b/core/src/jmh/java/io/grpc/internal/ChannelzBenchmark.java
@@ -17,8 +17,11 @@
 package io.grpc.internal;
 
 import com.google.common.util.concurrent.ListenableFuture;
-import io.grpc.internal.Channelz.ServerStats;
-import io.grpc.internal.Channelz.SocketStats;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ServerStats;
+import io.grpc.InternalChannelz.SocketStats;
+import io.grpc.LogId;
 import java.util.concurrent.TimeUnit;
 import org.openjdk.jmh.annotations.Benchmark;
 import org.openjdk.jmh.annotations.BenchmarkMode;
@@ -38,7 +41,7 @@ public class ChannelzBenchmark {
   @Param({"10", "100", "1000", "10000"})
   public int preexisting;
 
-  public Channelz channelz = new Channelz();
+  public InternalChannelz channelz = new InternalChannelz();
 
   public Instrumented<ServerStats> serverToRemove;
 
diff --git a/core/src/main/java/io/grpc/internal/Instrumented.java b/core/src/main/java/io/grpc/Instrumented.java
index c5ac8ee42..12de21455 100644
--- a/core/src/main/java/io/grpc/internal/Instrumented.java
+++ b/core/src/main/java/io/grpc/Instrumented.java
@@ -14,14 +14,17 @@
  * limitations under the License.
  */
 
-package io.grpc.internal;
+package io.grpc;
 
 import com.google.common.util.concurrent.ListenableFuture;
 
 /**
- * An interface for types that <b>may</b> support instrumentation. If the actual type does not
+ * An internal class. Do not use.
+ *
+ * <p>An interface for types that <b>may</b> support instrumentation. If the actual type does not
  * support instrumentation, then the future will return a {@code null}.
  */
+@Internal
 public interface Instrumented<T> extends WithLogId {
 
   /**
diff --git a/core/src/main/java/io/grpc/internal/Channelz.java b/core/src/main/java/io/grpc/InternalChannelz.java
index 1b8c8f268..ae3d3c490 100644
--- a/core/src/main/java/io/grpc/internal/Channelz.java
+++ b/core/src/main/java/io/grpc/InternalChannelz.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package io.grpc.internal;
+package io.grpc;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
@@ -22,7 +22,6 @@ import static com.google.common.base.Preconditions.checkState;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Objects;
-import io.grpc.ConnectivityState;
 import java.net.SocketAddress;
 import java.security.cert.Certificate;
 import java.util.ArrayList;
@@ -42,9 +41,13 @@ import javax.annotation.concurrent.Immutable;
 import javax.net.ssl.SSLPeerUnverifiedException;
 import javax.net.ssl.SSLSession;
 
-public final class Channelz {
-  private static final Logger log = Logger.getLogger(Channelz.class.getName());
-  private static final Channelz INSTANCE = new Channelz();
+/**
+ * This is an internal API. Do NOT use.
+ */
+@Internal
+public final class InternalChannelz {
+  private static final Logger log = Logger.getLogger(InternalChannelz.class.getName());
+  private static final InternalChannelz INSTANCE = new InternalChannelz();
 
   private final ConcurrentNavigableMap<Long, Instrumented<ServerStats>> servers
       = new ConcurrentSkipListMap<Long, Instrumented<ServerStats>>();
@@ -65,10 +68,10 @@ public final class Channelz {
   }
 
   @VisibleForTesting
-  public Channelz() {
+  public InternalChannelz() {
   }
 
-  public static Channelz instance() {
+  public static InternalChannelz instance() {
     return INSTANCE;
   }
 
diff --git a/core/src/main/java/io/grpc/internal/LogId.java b/core/src/main/java/io/grpc/LogId.java
index 27c90bf73..16395f291 100644
--- a/core/src/main/java/io/grpc/internal/LogId.java
+++ b/core/src/main/java/io/grpc/LogId.java
@@ -14,13 +14,16 @@
  * limitations under the License.
  */
 
-package io.grpc.internal;
+package io.grpc;
 
 import java.util.concurrent.atomic.AtomicLong;
 
 /**
- * An object that has an ID that is unique within the JVM, primarily for debug logging.
+ * An internal class. Do not use.
+ *
+ *<p>An object that has an ID that is unique within the JVM, primarily for debug logging.
  */
+@Internal
 public final class LogId {
   private static final AtomicLong idAlloc = new AtomicLong();
 
diff --git a/core/src/main/java/io/grpc/internal/WithLogId.java b/core/src/main/java/io/grpc/WithLogId.java
index 6bf6c4302..c846e2abe 100644
--- a/core/src/main/java/io/grpc/internal/WithLogId.java
+++ b/core/src/main/java/io/grpc/WithLogId.java
@@ -14,11 +14,14 @@
  * limitations under the License.
  */
 
-package io.grpc.internal;
+package io.grpc;
 
 /**
- * A loggable ID, unique for the duration of the program.
+ * An internal class. Do not use.
+ *
+ * <p>A loggable ID, unique for the duration of the program.
  */
+@Internal
 public interface WithLogId {
   /**
    * Returns an ID that is primarily used in debug logs. It usually contains the class name and a
diff --git a/core/src/main/java/io/grpc/inprocess/InProcessServer.java b/core/src/main/java/io/grpc/inprocess/InProcessServer.java
index 95a7b0860..ff0292d30 100644
--- a/core/src/main/java/io/grpc/inprocess/InProcessServer.java
+++ b/core/src/main/java/io/grpc/inprocess/InProcessServer.java
@@ -19,9 +19,9 @@ package io.grpc.inprocess;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.base.MoreObjects;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz.SocketStats;
 import io.grpc.ServerStreamTracer;
-import io.grpc.internal.Channelz.SocketStats;
-import io.grpc.internal.Instrumented;
 import io.grpc.internal.InternalServer;
 import io.grpc.internal.ObjectPool;
 import io.grpc.internal.ServerListener;
diff --git a/core/src/main/java/io/grpc/inprocess/InProcessTransport.java b/core/src/main/java/io/grpc/inprocess/InProcessTransport.java
index 90e5016cd..45353bc11 100644
--- a/core/src/main/java/io/grpc/inprocess/InProcessTransport.java
+++ b/core/src/main/java/io/grpc/inprocess/InProcessTransport.java
@@ -31,17 +31,17 @@ import io.grpc.Deadline;
 import io.grpc.Decompressor;
 import io.grpc.DecompressorRegistry;
 import io.grpc.Grpc;
+import io.grpc.InternalChannelz.SocketStats;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.SecurityLevel;
 import io.grpc.ServerStreamTracer;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.SocketStats;
 import io.grpc.internal.ClientStream;
 import io.grpc.internal.ClientStreamListener;
 import io.grpc.internal.ConnectionClientTransport;
 import io.grpc.internal.GrpcUtil;
-import io.grpc.internal.LogId;
 import io.grpc.internal.ManagedClientTransport;
 import io.grpc.internal.NoopClientStream;
 import io.grpc.internal.ObjectPool;
diff --git a/core/src/main/java/io/grpc/internal/AbstractManagedChannelImplBuilder.java b/core/src/main/java/io/grpc/internal/AbstractManagedChannelImplBuilder.java
index ab603c673..ada5a2ba9 100644
--- a/core/src/main/java/io/grpc/internal/AbstractManagedChannelImplBuilder.java
+++ b/core/src/main/java/io/grpc/internal/AbstractManagedChannelImplBuilder.java
@@ -27,6 +27,7 @@ import io.grpc.ClientInterceptor;
 import io.grpc.CompressorRegistry;
 import io.grpc.DecompressorRegistry;
 import io.grpc.EquivalentAddressGroup;
+import io.grpc.InternalChannelz;
 import io.grpc.LoadBalancer;
 import io.grpc.ManagedChannel;
 import io.grpc.ManagedChannelBuilder;
@@ -134,7 +135,7 @@ public abstract class AbstractManagedChannelImplBuilder
   // TODO(zdapeng): delete me
   boolean temporarilyDisableRetry;
 
-  Channelz channelz = Channelz.instance();
+  InternalChannelz channelz = InternalChannelz.instance();
   int maxTraceEvents;
 
   protected TransportTracer.Factory transportTracerFactory = TransportTracer.getDefaultFactory();
diff --git a/core/src/main/java/io/grpc/internal/AbstractServerImplBuilder.java b/core/src/main/java/io/grpc/internal/AbstractServerImplBuilder.java
index 23d42bd43..3e1b7afbe 100644
--- a/core/src/main/java/io/grpc/internal/AbstractServerImplBuilder.java
+++ b/core/src/main/java/io/grpc/internal/AbstractServerImplBuilder.java
@@ -28,6 +28,7 @@ import io.grpc.Context;
 import io.grpc.DecompressorRegistry;
 import io.grpc.HandlerRegistry;
 import io.grpc.Internal;
+import io.grpc.InternalChannelz;
 import io.grpc.InternalNotifyOnServerBuild;
 import io.grpc.Server;
 import io.grpc.ServerBuilder;
@@ -113,7 +114,7 @@ public abstract class AbstractServerImplBuilder<T extends AbstractServerImplBuil
   protected BinaryLog binlog;
   protected TransportTracer.Factory transportTracerFactory = TransportTracer.getDefaultFactory();
 
-  protected Channelz channelz = Channelz.instance();
+  protected InternalChannelz channelz = InternalChannelz.instance();
   protected CallTracer.Factory callTracerFactory = CallTracer.getDefaultFactory();
 
   @Override
diff --git a/core/src/main/java/io/grpc/internal/AbstractSubchannel.java b/core/src/main/java/io/grpc/internal/AbstractSubchannel.java
index 1e946c929..26e6f0576 100644
--- a/core/src/main/java/io/grpc/internal/AbstractSubchannel.java
+++ b/core/src/main/java/io/grpc/internal/AbstractSubchannel.java
@@ -17,8 +17,9 @@
 package io.grpc.internal;
 
 import com.google.common.annotations.VisibleForTesting;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz.ChannelStats;
 import io.grpc.LoadBalancer;
-import io.grpc.internal.Channelz.ChannelStats;
 import javax.annotation.Nullable;
 
 /**
diff --git a/core/src/main/java/io/grpc/internal/CallTracer.java b/core/src/main/java/io/grpc/internal/CallTracer.java
index be1779469..330323d1b 100644
--- a/core/src/main/java/io/grpc/internal/CallTracer.java
+++ b/core/src/main/java/io/grpc/internal/CallTracer.java
@@ -18,8 +18,8 @@ package io.grpc.internal;
 
 import static io.grpc.internal.TimeProvider.SYSTEM_TIME_PROVIDER;
 
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ServerStats;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ServerStats;
 
 /**
  * A collection of call stats for channelz.
diff --git a/core/src/main/java/io/grpc/internal/ChannelTracer.java b/core/src/main/java/io/grpc/internal/ChannelTracer.java
index 654dead31..6e8fb92eb 100644
--- a/core/src/main/java/io/grpc/internal/ChannelTracer.java
+++ b/core/src/main/java/io/grpc/internal/ChannelTracer.java
@@ -19,9 +19,9 @@ package io.grpc.internal;
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ChannelTrace;
-import io.grpc.internal.Channelz.ChannelTrace.Event;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ChannelTrace;
+import io.grpc.InternalChannelz.ChannelTrace.Event;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collection;
diff --git a/core/src/main/java/io/grpc/internal/ClientTransport.java b/core/src/main/java/io/grpc/internal/ClientTransport.java
index 1c3b5ad7a..767f8b53b 100644
--- a/core/src/main/java/io/grpc/internal/ClientTransport.java
+++ b/core/src/main/java/io/grpc/internal/ClientTransport.java
@@ -17,9 +17,10 @@
 package io.grpc.internal;
 
 import io.grpc.CallOptions;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz.SocketStats;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
-import io.grpc.internal.Channelz.SocketStats;
 import java.util.concurrent.Executor;
 import javax.annotation.concurrent.ThreadSafe;
 
diff --git a/core/src/main/java/io/grpc/internal/DelayedClientTransport.java b/core/src/main/java/io/grpc/internal/DelayedClientTransport.java
index 31850371e..0679de32d 100644
--- a/core/src/main/java/io/grpc/internal/DelayedClientTransport.java
+++ b/core/src/main/java/io/grpc/internal/DelayedClientTransport.java
@@ -21,13 +21,14 @@ import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.SettableFuture;
 import io.grpc.CallOptions;
 import io.grpc.Context;
+import io.grpc.InternalChannelz.SocketStats;
 import io.grpc.LoadBalancer.PickResult;
 import io.grpc.LoadBalancer.PickSubchannelArgs;
 import io.grpc.LoadBalancer.SubchannelPicker;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.SocketStats;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
diff --git a/core/src/main/java/io/grpc/internal/FailingClientTransport.java b/core/src/main/java/io/grpc/internal/FailingClientTransport.java
index 0d33d65c4..5d24d5bb9 100644
--- a/core/src/main/java/io/grpc/internal/FailingClientTransport.java
+++ b/core/src/main/java/io/grpc/internal/FailingClientTransport.java
@@ -21,10 +21,11 @@ import com.google.common.base.Preconditions;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.SettableFuture;
 import io.grpc.CallOptions;
+import io.grpc.InternalChannelz.SocketStats;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.SocketStats;
 import io.grpc.internal.ClientStreamListener.RpcProgress;
 import java.util.concurrent.Executor;
 
diff --git a/core/src/main/java/io/grpc/internal/ForwardingConnectionClientTransport.java b/core/src/main/java/io/grpc/internal/ForwardingConnectionClientTransport.java
index 808e5d2a0..0873284ac 100644
--- a/core/src/main/java/io/grpc/internal/ForwardingConnectionClientTransport.java
+++ b/core/src/main/java/io/grpc/internal/ForwardingConnectionClientTransport.java
@@ -20,10 +20,11 @@ import com.google.common.base.MoreObjects;
 import com.google.common.util.concurrent.ListenableFuture;
 import io.grpc.Attributes;
 import io.grpc.CallOptions;
+import io.grpc.InternalChannelz.SocketStats;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.SocketStats;
 import java.util.concurrent.Executor;
 
 abstract class ForwardingConnectionClientTransport implements ConnectionClientTransport {
diff --git a/core/src/main/java/io/grpc/internal/GrpcUtil.java b/core/src/main/java/io/grpc/internal/GrpcUtil.java
index aa157f9e9..eb2bf66a7 100644
--- a/core/src/main/java/io/grpc/internal/GrpcUtil.java
+++ b/core/src/main/java/io/grpc/internal/GrpcUtil.java
@@ -29,14 +29,15 @@ import com.google.common.util.concurrent.MoreExecutors;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import io.grpc.CallOptions;
 import io.grpc.ClientStreamTracer;
+import io.grpc.InternalChannelz.SocketStats;
 import io.grpc.InternalMetadata;
 import io.grpc.InternalMetadata.TrustedAsciiMarshaller;
 import io.grpc.LoadBalancer.PickResult;
 import io.grpc.LoadBalancer.Subchannel;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.SocketStats;
 import io.grpc.internal.ClientStreamListener.RpcProgress;
 import io.grpc.internal.SharedResourceHolder.Resource;
 import io.grpc.internal.StreamListener.MessageProducer;
diff --git a/core/src/main/java/io/grpc/internal/InternalServer.java b/core/src/main/java/io/grpc/internal/InternalServer.java
index 16f4e104e..35cb14d56 100644
--- a/core/src/main/java/io/grpc/internal/InternalServer.java
+++ b/core/src/main/java/io/grpc/internal/InternalServer.java
@@ -16,7 +16,8 @@
 
 package io.grpc.internal;
 
-import io.grpc.internal.Channelz.SocketStats;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz.SocketStats;
 import java.io.IOException;
 import java.util.List;
 import javax.annotation.concurrent.ThreadSafe;
diff --git a/core/src/main/java/io/grpc/internal/InternalSubchannel.java b/core/src/main/java/io/grpc/internal/InternalSubchannel.java
index f386545f8..7979f06bb 100644
--- a/core/src/main/java/io/grpc/internal/InternalSubchannel.java
+++ b/core/src/main/java/io/grpc/internal/InternalSubchannel.java
@@ -35,11 +35,15 @@ import io.grpc.CallOptions;
 import io.grpc.ConnectivityState;
 import io.grpc.ConnectivityStateInfo;
 import io.grpc.EquivalentAddressGroup;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ChannelTrace;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ChannelTrace;
+import io.grpc.WithLogId;
 import java.net.SocketAddress;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -69,7 +73,7 @@ final class InternalSubchannel implements Instrumented<ChannelStats> {
   private final Callback callback;
   private final ClientTransportFactory transportFactory;
   private final ScheduledExecutorService scheduledExecutor;
-  private final Channelz channelz;
+  private final InternalChannelz channelz;
   private final CallTracer callsTracer;
   @CheckForNull
   private final ChannelTracer channelTracer;
@@ -162,7 +166,7 @@ final class InternalSubchannel implements Instrumented<ChannelStats> {
       BackoffPolicy.Provider backoffPolicyProvider,
       ClientTransportFactory transportFactory, ScheduledExecutorService scheduledExecutor,
       Supplier<Stopwatch> stopwatchSupplier, ChannelExecutor channelExecutor, Callback callback,
-      Channelz channelz, CallTracer callsTracer, @Nullable ChannelTracer channelTracer,
+      InternalChannelz channelz, CallTracer callsTracer, @Nullable ChannelTracer channelTracer,
       TimeProvider timeProvider) {
     Preconditions.checkNotNull(addressGroups, "addressGroups");
     Preconditions.checkArgument(!addressGroups.isEmpty(), "addressGroups is empty");
diff --git a/core/src/main/java/io/grpc/internal/ManagedChannelImpl.java b/core/src/main/java/io/grpc/internal/ManagedChannelImpl.java
index 020edef0e..8153bc539 100644
--- a/core/src/main/java/io/grpc/internal/ManagedChannelImpl.java
+++ b/core/src/main/java/io/grpc/internal/ManagedChannelImpl.java
@@ -44,17 +44,21 @@ import io.grpc.ConnectivityStateInfo;
 import io.grpc.Context;
 import io.grpc.DecompressorRegistry;
 import io.grpc.EquivalentAddressGroup;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ChannelTrace;
 import io.grpc.LoadBalancer;
 import io.grpc.LoadBalancer.PickResult;
 import io.grpc.LoadBalancer.PickSubchannelArgs;
 import io.grpc.LoadBalancer.SubchannelPicker;
+import io.grpc.LogId;
 import io.grpc.ManagedChannel;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.NameResolver;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ChannelTrace;
+import io.grpc.WithLogId;
 import io.grpc.internal.ClientCallImpl.ClientTransportProvider;
 import io.grpc.internal.RetriableStream.ChannelBufferMeter;
 import io.grpc.internal.RetriableStream.Throttle;
@@ -211,7 +215,7 @@ final class ManagedChannelImpl extends ManagedChannel implements Instrumented<Ch
   private final CallTracer channelCallTracer;
   @CheckForNull
   private final ChannelTracer channelTracer;
-  private final Channelz channelz;
+  private final InternalChannelz channelz;
   @CheckForNull
   private Boolean haveBackends; // a flag for doing channel tracing when flipped
   @Nullable
@@ -297,7 +301,7 @@ final class ManagedChannelImpl extends ManagedChannel implements Instrumented<Ch
     channelExecutor.executeLater(new Runnable() {
       @Override
       public void run() {
-        ChannelStats.Builder builder = new Channelz.ChannelStats.Builder();
+        ChannelStats.Builder builder = new InternalChannelz.ChannelStats.Builder();
         channelCallTracer.updateBuilder(builder);
         if (channelTracer != null) {
           channelTracer.updateBuilder(builder);
diff --git a/core/src/main/java/io/grpc/internal/OobChannel.java b/core/src/main/java/io/grpc/internal/OobChannel.java
index 95368c0e7..3e71fe45c 100644
--- a/core/src/main/java/io/grpc/internal/OobChannel.java
+++ b/core/src/main/java/io/grpc/internal/OobChannel.java
@@ -30,17 +30,21 @@ import io.grpc.ConnectivityState;
 import io.grpc.ConnectivityStateInfo;
 import io.grpc.Context;
 import io.grpc.EquivalentAddressGroup;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ChannelTrace;
 import io.grpc.LoadBalancer;
 import io.grpc.LoadBalancer.PickResult;
 import io.grpc.LoadBalancer.PickSubchannelArgs;
 import io.grpc.LoadBalancer.Subchannel;
 import io.grpc.LoadBalancer.SubchannelPicker;
+import io.grpc.LogId;
 import io.grpc.ManagedChannel;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ChannelTrace;
+import io.grpc.WithLogId;
 import io.grpc.internal.ClientCallImpl.ClientTransportProvider;
 import java.util.Collections;
 import java.util.List;
@@ -69,7 +73,7 @@ final class OobChannel extends ManagedChannel implements Instrumented<ChannelSta
   private final LogId logId = LogId.allocate(getClass().getName());
   private final String authority;
   private final DelayedClientTransport delayedTransport;
-  private final Channelz channelz;
+  private final InternalChannelz channelz;
   private final ObjectPool<? extends Executor> executorPool;
   private final Executor executor;
   private final ScheduledExecutorService deadlineCancellationExecutor;
@@ -99,7 +103,7 @@ final class OobChannel extends ManagedChannel implements Instrumented<ChannelSta
   OobChannel(
       String authority, ObjectPool<? extends Executor> executorPool,
       ScheduledExecutorService deadlineCancellationExecutor, ChannelExecutor channelExecutor,
-      CallTracer callsTracer, @Nullable  ChannelTracer channelTracer, Channelz channelz,
+      CallTracer callsTracer, @Nullable  ChannelTracer channelTracer, InternalChannelz channelz,
       TimeProvider timeProvider) {
     this.authority = checkNotNull(authority, "authority");
     this.executorPool = checkNotNull(executorPool, "executorPool");
diff --git a/core/src/main/java/io/grpc/internal/ServerImpl.java b/core/src/main/java/io/grpc/internal/ServerImpl.java
index 9dd238501..8e149e670 100644
--- a/core/src/main/java/io/grpc/internal/ServerImpl.java
+++ b/core/src/main/java/io/grpc/internal/ServerImpl.java
@@ -36,7 +36,11 @@ import io.grpc.Context;
 import io.grpc.Decompressor;
 import io.grpc.DecompressorRegistry;
 import io.grpc.HandlerRegistry;
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ServerStats;
 import io.grpc.InternalServerInterceptors;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.ServerCall;
 import io.grpc.ServerCallHandler;
@@ -45,7 +49,6 @@ import io.grpc.ServerMethodDefinition;
 import io.grpc.ServerServiceDefinition;
 import io.grpc.ServerTransportFilter;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.ServerStats;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
@@ -111,7 +114,7 @@ public final class ServerImpl extends io.grpc.Server implements Instrumented<Ser
   private final CompressorRegistry compressorRegistry;
   private final BinaryLog binlog;
 
-  private final Channelz channelz;
+  private final InternalChannelz channelz;
   private final CallTracer serverCallTracer;
 
   /**
diff --git a/core/src/main/java/io/grpc/internal/ServerTransport.java b/core/src/main/java/io/grpc/internal/ServerTransport.java
index 11215a759..a7f9d71a6 100644
--- a/core/src/main/java/io/grpc/internal/ServerTransport.java
+++ b/core/src/main/java/io/grpc/internal/ServerTransport.java
@@ -16,8 +16,9 @@
 
 package io.grpc.internal;
 
+import io.grpc.Instrumented;
+import io.grpc.InternalChannelz.SocketStats;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.SocketStats;
 import java.util.concurrent.ScheduledExecutorService;
 
 /** An inbound connection. */
diff --git a/core/src/main/java/io/grpc/internal/TransportTracer.java b/core/src/main/java/io/grpc/internal/TransportTracer.java
index 808ce6b96..f2b400b8b 100644
--- a/core/src/main/java/io/grpc/internal/TransportTracer.java
+++ b/core/src/main/java/io/grpc/internal/TransportTracer.java
@@ -20,7 +20,7 @@ import static io.grpc.internal.TimeProvider.SYSTEM_TIME_PROVIDER;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
-import io.grpc.internal.Channelz.TransportStats;
+import io.grpc.InternalChannelz.TransportStats;
 
 /**
  * A class for gathering statistics about a transport. This is an experimental feature.
diff --git a/core/src/test/java/io/grpc/internal/ChannelzTest.java b/core/src/test/java/io/grpc/InternalChannelzTest.java
index 53263edc1..40be853bc 100644
--- a/core/src/test/java/io/grpc/internal/ChannelzTest.java
+++ b/core/src/test/java/io/grpc/InternalChannelzTest.java
@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-package io.grpc.internal;
+package io.grpc;
 
 import static com.google.common.truth.Truth.assertThat;
-import static io.grpc.internal.Channelz.id;
+import static io.grpc.InternalChannelz.id;
 import static junit.framework.TestCase.assertTrue;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -28,13 +28,13 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
 import com.google.common.util.concurrent.ListenableFuture;
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.RootChannelList;
-import io.grpc.internal.Channelz.ServerList;
-import io.grpc.internal.Channelz.ServerSocketsList;
-import io.grpc.internal.Channelz.ServerStats;
-import io.grpc.internal.Channelz.SocketStats;
-import io.grpc.internal.Channelz.Tls;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.RootChannelList;
+import io.grpc.InternalChannelz.ServerList;
+import io.grpc.InternalChannelz.ServerSocketsList;
+import io.grpc.InternalChannelz.ServerStats;
+import io.grpc.InternalChannelz.SocketStats;
+import io.grpc.InternalChannelz.Tls;
 import java.security.cert.Certificate;
 import javax.net.ssl.SSLSession;
 import org.junit.Test;
@@ -42,9 +42,9 @@ import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
 
 @RunWith(JUnit4.class)
-public final class ChannelzTest {
+public final class InternalChannelzTest {
 
-  private final Channelz channelz = new Channelz();
+  private final InternalChannelz channelz = new InternalChannelz();
 
   @Test
   public void getRootChannels_empty() {
diff --git a/core/src/test/java/io/grpc/internal/ChannelTracerTest.java b/core/src/test/java/io/grpc/internal/ChannelTracerTest.java
index 1d73a4cb3..1603a54bc 100644
--- a/core/src/test/java/io/grpc/internal/ChannelTracerTest.java
+++ b/core/src/test/java/io/grpc/internal/ChannelTracerTest.java
@@ -18,9 +18,9 @@ package io.grpc.internal;
 
 import static com.google.common.truth.Truth.assertThat;
 
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ChannelTrace.Event;
-import io.grpc.internal.Channelz.ChannelTrace.Event.Severity;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ChannelTrace.Event;
+import io.grpc.InternalChannelz.ChannelTrace.Event.Severity;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
diff --git a/core/src/test/java/io/grpc/internal/InternalSubchannelTest.java b/core/src/test/java/io/grpc/internal/InternalSubchannelTest.java
index 69ef5f07b..95f099b64 100644
--- a/core/src/test/java/io/grpc/internal/InternalSubchannelTest.java
+++ b/core/src/test/java/io/grpc/internal/InternalSubchannelTest.java
@@ -41,7 +41,9 @@ import com.google.common.collect.Iterables;
 import io.grpc.Attributes;
 import io.grpc.ConnectivityStateInfo;
 import io.grpc.EquivalentAddressGroup;
+import io.grpc.InternalChannelz;
 import io.grpc.Status;
+import io.grpc.WithLogId;
 import io.grpc.internal.InternalSubchannel.CallTracingTransport;
 import io.grpc.internal.InternalSubchannel.Index;
 import io.grpc.internal.TestUtils.MockClientTransportInfo;
@@ -79,7 +81,7 @@ public class InternalSubchannelTest {
   private final FakeClock fakeExecutor = new FakeClock();
   private final ChannelExecutor channelExecutor = new ChannelExecutor();
 
-  private final Channelz channelz = new Channelz();
+  private final InternalChannelz channelz = new InternalChannelz();
 
   @Mock private BackoffPolicy mockBackoffPolicy1;
   @Mock private BackoffPolicy mockBackoffPolicy2;
diff --git a/core/src/test/java/io/grpc/internal/ManagedChannelImplTest.java b/core/src/test/java/io/grpc/internal/ManagedChannelImplTest.java
index 6c883463c..783fb400d 100644
--- a/core/src/test/java/io/grpc/internal/ManagedChannelImplTest.java
+++ b/core/src/test/java/io/grpc/internal/ManagedChannelImplTest.java
@@ -68,7 +68,11 @@ import io.grpc.ConnectivityState;
 import io.grpc.ConnectivityStateInfo;
 import io.grpc.Context;
 import io.grpc.EquivalentAddressGroup;
+import io.grpc.Instrumented;
 import io.grpc.IntegerMarshaller;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ChannelStats;
+import io.grpc.InternalChannelz.ChannelTrace;
 import io.grpc.LoadBalancer;
 import io.grpc.LoadBalancer.Helper;
 import io.grpc.LoadBalancer.PickResult;
@@ -84,8 +88,6 @@ import io.grpc.SecurityLevel;
 import io.grpc.ServerMethodDefinition;
 import io.grpc.Status;
 import io.grpc.StringMarshaller;
-import io.grpc.internal.Channelz.ChannelStats;
-import io.grpc.internal.Channelz.ChannelTrace;
 import io.grpc.internal.ClientTransportFactory.ClientTransportOptions;
 import io.grpc.internal.TestUtils.MockClientTransportInfo;
 import io.grpc.stub.ClientCalls;
@@ -165,7 +167,7 @@ public class ManagedChannelImplTest {
         }
       };
 
-  private final Channelz channelz = new Channelz();
+  private final InternalChannelz channelz = new InternalChannelz();
 
   @Rule public final ExpectedException thrown = ExpectedException.none();
 
diff --git a/core/src/test/java/io/grpc/internal/MessageDeframerTest.java b/core/src/test/java/io/grpc/internal/MessageDeframerTest.java
index ab2a4c1d7..8b6fc1da9 100644
--- a/core/src/test/java/io/grpc/internal/MessageDeframerTest.java
+++ b/core/src/test/java/io/grpc/internal/MessageDeframerTest.java
@@ -35,9 +35,9 @@ import com.google.common.base.Charsets;
 import com.google.common.io.ByteStreams;
 import com.google.common.primitives.Bytes;
 import io.grpc.Codec;
+import io.grpc.InternalChannelz.TransportStats;
 import io.grpc.StatusRuntimeException;
 import io.grpc.StreamTracer;
-import io.grpc.internal.Channelz.TransportStats;
 import io.grpc.internal.MessageDeframer.Listener;
 import io.grpc.internal.MessageDeframer.SizeEnforcingInputStream;
 import io.grpc.internal.testing.TestStreamTracer.TestBaseStreamTracer;
diff --git a/core/src/test/java/io/grpc/internal/ServerCallImplTest.java b/core/src/test/java/io/grpc/internal/ServerCallImplTest.java
index 57bc4be2f..cff8caebc 100644
--- a/core/src/test/java/io/grpc/internal/ServerCallImplTest.java
+++ b/core/src/test/java/io/grpc/internal/ServerCallImplTest.java
@@ -34,14 +34,14 @@ import com.google.common.io.CharStreams;
 import io.grpc.CompressorRegistry;
 import io.grpc.Context;
 import io.grpc.DecompressorRegistry;
+import io.grpc.InternalChannelz.ServerStats;
+import io.grpc.InternalChannelz.ServerStats.Builder;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.MethodDescriptor.Marshaller;
 import io.grpc.MethodDescriptor.MethodType;
 import io.grpc.ServerCall;
 import io.grpc.Status;
-import io.grpc.internal.Channelz.ServerStats;
-import io.grpc.internal.Channelz.ServerStats.Builder;
 import io.grpc.internal.ServerCallImpl.ServerStreamListenerImpl;
 import io.grpc.internal.testing.SingleMessageProducer;
 import java.io.ByteArrayInputStream;
diff --git a/core/src/test/java/io/grpc/internal/ServerImplTest.java b/core/src/test/java/io/grpc/internal/ServerImplTest.java
index d007a749a..56e7bb3ac 100644
--- a/core/src/test/java/io/grpc/internal/ServerImplTest.java
+++ b/core/src/test/java/io/grpc/internal/ServerImplTest.java
@@ -17,7 +17,7 @@
 package io.grpc.internal;
 
 import static com.google.common.truth.Truth.assertThat;
-import static io.grpc.internal.Channelz.id;
+import static io.grpc.InternalChannelz.id;
 import static io.grpc.internal.GrpcUtil.MESSAGE_ENCODING_KEY;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -54,8 +54,13 @@ import io.grpc.Compressor;
 import io.grpc.Context;
 import io.grpc.Grpc;
 import io.grpc.HandlerRegistry;
+import io.grpc.Instrumented;
 import io.grpc.IntegerMarshaller;
+import io.grpc.InternalChannelz;
+import io.grpc.InternalChannelz.ServerSocketsList;
+import io.grpc.InternalChannelz.SocketStats;
 import io.grpc.InternalServerInterceptors;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.ServerCall;
@@ -69,8 +74,6 @@ import io.grpc.ServerTransportFilter;
 import io.grpc.ServiceDescriptor;
 import io.grpc.Status;
 import io.grpc.StringMarshaller;
-import io.grpc.internal.Channelz.ServerSocketsList;
-import io.grpc.internal.Channelz.SocketStats;
 import io.grpc.internal.ServerImpl.JumpToApplicationThreadServerStreamListener;
 import io.grpc.internal.testing.SingleMessageProducer;
 import io.grpc.internal.testing.TestServerStreamTracer;
@@ -142,7 +145,7 @@ public class ServerImplTest {
 
   private final FakeClock executor = new FakeClock();
   private final FakeClock timer = new FakeClock();
-  private final Channelz channelz = new Channelz();
+  private final InternalChannelz channelz = new InternalChannelz();
 
   @Mock
   private ServerStreamTracer.Factory streamTracerFactory;
diff --git a/core/src/test/java/io/grpc/internal/TestUtils.java b/core/src/test/java/io/grpc/internal/TestUtils.java
index 526a8fb03..b2b20cb28 100644
--- a/core/src/test/java/io/grpc/internal/TestUtils.java
+++ b/core/src/test/java/io/grpc/internal/TestUtils.java
@@ -22,6 +22,7 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
 import io.grpc.CallOptions;
+import io.grpc.LogId;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import java.net.SocketAddress;