diff --git a/core/src/test/java/io/grpc/CallOptionsTest.java b/core/src/test/java/io/grpc/CallOptionsTest.java
index 7f815bd610c..7b311489c73 100644
--- a/core/src/test/java/io/grpc/CallOptionsTest.java
+++ b/core/src/test/java/io/grpc/CallOptionsTest.java
@@ -42,14 +42,14 @@ public class CallOptionsTest {
       = CallOptions.Key.createWithDefault("option1", "default");
   private static final CallOptions.Key<String> OPTION_2
       = CallOptions.Key.createWithDefault("option2", "default");
-  private String sampleAuthority = "authority";
-  private String sampleCompressor = "compressor";
-  private Deadline.Ticker ticker = new FakeTicker();
-  private Deadline sampleDeadline = Deadline.after(1, NANOSECONDS, ticker);
-  private CallCredentials sampleCreds = mock(CallCredentials.class);
-  private ClientStreamTracer.Factory tracerFactory1 = new FakeTracerFactory("tracerFactory1");
-  private ClientStreamTracer.Factory tracerFactory2 = new FakeTracerFactory("tracerFactory2");
-  private CallOptions allSet = CallOptions.DEFAULT
+  private final String sampleAuthority = "authority";
+  private final String sampleCompressor = "compressor";
+  private final Deadline.Ticker ticker = new FakeTicker();
+  private final Deadline sampleDeadline = Deadline.after(1, NANOSECONDS, ticker);
+  private final CallCredentials sampleCreds = mock(CallCredentials.class);
+  private final ClientStreamTracer.Factory tracerFactory1 = new FakeTracerFactory("tracerFactory1");
+  private final ClientStreamTracer.Factory tracerFactory2 = new FakeTracerFactory("tracerFactory2");
+  private final CallOptions allSet = CallOptions.DEFAULT
       .withAuthority(sampleAuthority)
       .withDeadline(sampleDeadline)
       .withCallCredentials(sampleCreds)
diff --git a/examples/src/main/java/io/grpc/examples/advanced/JsonMarshaller.java b/examples/src/main/java/io/grpc/examples/advanced/JsonMarshaller.java
index 7b9aae94f8f..8b3068cc009 100644
--- a/examples/src/main/java/io/grpc/examples/advanced/JsonMarshaller.java
+++ b/examples/src/main/java/io/grpc/examples/advanced/JsonMarshaller.java
@@ -22,7 +22,6 @@
 import com.google.protobuf.util.JsonFormat;
 import com.google.protobuf.util.JsonFormat.Parser;
 import com.google.protobuf.util.JsonFormat.Printer;
-import io.grpc.ExperimentalApi;
 import io.grpc.MethodDescriptor.Marshaller;
 import io.grpc.Status;
 import java.io.ByteArrayInputStream;
diff --git a/netty/src/main/java/io/grpc/netty/GrpcHttp2ConnectionHandler.java b/netty/src/main/java/io/grpc/netty/GrpcHttp2ConnectionHandler.java
index 5203b58c714..771bcd2495d 100644
--- a/netty/src/main/java/io/grpc/netty/GrpcHttp2ConnectionHandler.java
+++ b/netty/src/main/java/io/grpc/netty/GrpcHttp2ConnectionHandler.java
@@ -73,6 +73,7 @@ public void handleProtocolNegotiationCompleted(Attributes attrs, Channelz.Securi
    * useful if the channel will soon be deregistered from the executor and used in a non-Netty
    * context.
    */
+  @SuppressWarnings("FutureReturnValueIgnored")
   public void notifyUnused() {
     channelUnused.setSuccess(null);
   }
diff --git a/services/src/main/java/io/grpc/services/BinaryLogProviderImpl.java b/services/src/main/java/io/grpc/services/BinaryLogProviderImpl.java
index 907295ea38f..826e2af8d08 100644
--- a/services/src/main/java/io/grpc/services/BinaryLogProviderImpl.java
+++ b/services/src/main/java/io/grpc/services/BinaryLogProviderImpl.java
@@ -23,14 +23,12 @@
 import io.grpc.ServerInterceptor;
 import java.io.IOException;
 import java.util.concurrent.atomic.AtomicLong;
-import java.util.logging.Logger;
 import javax.annotation.Nullable;
 
 /**
  * The default implementation of a {@link BinaryLogProvider}.
  */
 class BinaryLogProviderImpl extends BinaryLogProvider {
-  private static final Logger logger = Logger.getLogger(BinaryLogProviderImpl.class.getName());
   private final BinlogHelper.Factory factory;
   private final BinaryLogSink sink;
   private final AtomicLong counter = new AtomicLong();