HBASE-9461 Some doc and cleanup in RPCServer

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523386 13f79535-47bb-0310-9956-ffa450edef68

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/CallRunner.java

@@ -0,0 +1,148 @@
+package org.apache.hadoop.hbase.ipc;
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.nio.channels.ClosedChannelException;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ipc.RpcServer.Call;
+import org.apache.hadoop.hbase.monitoring.MonitoredRPCHandler;
+import org.apache.hadoop.hbase.monitoring.TaskMonitor;
+import org.apache.hadoop.hbase.security.User;
+import org.apache.hadoop.hbase.util.Pair;
+import org.apache.hadoop.security.UserGroupInformation;
+import org.apache.hadoop.util.StringUtils;
+import org.cloudera.htrace.Trace;
+import org.cloudera.htrace.TraceScope;
+
+import com.google.protobuf.Message;
+
+/**
+ * The request processing logic, which is usually executed in thread pools provided by an
+ * {@link RpcScheduler}.  Call {@link #run()} to actually execute the contained
+ * {@link RpcServer.Call}
+ */
+@InterfaceAudience.Private
+public class CallRunner {
+  private final Call call;
+  private final RpcServerInterface rpcServer;
+  private final MonitoredRPCHandler status;
+
+  /**
+   * On construction, adds the size of this call to the running count of outstanding call sizes.
+   * Presumption is that we are put on a queue while we wait on an executor to run us.  During this
+   * time we occupy heap.
+   * @param call The call to run.
+   * @param rpcServer
+   */
+  // The constructor is shutdown so only RpcServer in this class can make one of these.
+  CallRunner(final RpcServerInterface rpcServer, final Call call) {
+    this.call = call;
+    this.rpcServer = rpcServer;
+    // Add size of the call to queue size.
+    this.rpcServer.addCallSize(call.getSize());
+    this.status = getStatus();
+  }
+
+  public Call getCall() {
+    return call;
+  }
+
+  public void run() {
+    try {
+      this.status.setStatus("Setting up call");
+      this.status.setConnection(call.connection.getHostAddress(), call.connection.getRemotePort());
+      if (RpcServer.LOG.isDebugEnabled()) {
+        UserGroupInformation remoteUser = call.connection.user;
+        RpcServer.LOG.debug(call.toShortString() + " executing as " +
+            ((remoteUser == null) ? "NULL principal" : remoteUser.getUserName()));
+      }
+      Throwable errorThrowable = null;
+      String error = null;
+      Pair<Message, CellScanner> resultPair = null;
+      RpcServer.CurCall.set(call);
+      TraceScope traceScope = null;
+      try {
+        if (!this.rpcServer.isStarted()) {
+          throw new ServerNotRunningYetException("Server is not running yet");
+        }
+        if (call.tinfo != null) {
+          traceScope = Trace.startSpan(call.toTraceString(), call.tinfo);
+        }
+        RequestContext.set(User.create(call.connection.user), RpcServer.getRemoteIp(),
+          call.connection.service);
+        // make the call
+        resultPair = this.rpcServer.call(call.service, call.md, call.param, call.cellScanner,
+          call.timestamp, this.status);
+      } catch (Throwable e) {
+        RpcServer.LOG.debug(Thread.currentThread().getName() + ": " + call.toShortString(), e);
+        errorThrowable = e;
+        error = StringUtils.stringifyException(e);
+      } finally {
+        if (traceScope != null) {
+          traceScope.close();
+        }
+        // Must always clear the request context to avoid leaking
+        // credentials between requests.
+        RequestContext.clear();
+      }
+      RpcServer.CurCall.set(null);
+      this.rpcServer.addCallSize(call.getSize() * -1);
+      // Set the response for undelayed calls and delayed calls with
+      // undelayed responses.
+      if (!call.isDelayed() || !call.isReturnValueDelayed()) {
+        Message param = resultPair != null ? resultPair.getFirst() : null;
+        CellScanner cells = resultPair != null ? resultPair.getSecond() : null;
+        call.setResponse(param, cells, errorThrowable, error);
+      }
+      call.sendResponseIfReady();
+      this.status.markComplete("Sent response");
+      this.status.pause("Waiting for a call");
+    } catch (OutOfMemoryError e) {
+      if (this.rpcServer.getErrorHandler() != null) {
+        if (this.rpcServer.getErrorHandler().checkOOME(e)) {
+          RpcServer.LOG.info(Thread.currentThread().getName() + ": exiting on OutOfMemoryError");
+          return;
+        }
+      } else {
+        // rethrow if no handler
+        throw e;
+      }
+    } catch (ClosedChannelException cce) {
+      RpcServer.LOG.warn(Thread.currentThread().getName() + ": caught a ClosedChannelException, " +
+          "this means that the server was processing a " +
+          "request but the client went away. The error message was: " +
+          cce.getMessage());
+    } catch (Exception e) {
+      RpcServer.LOG.warn(Thread.currentThread().getName()
+          + ": caught: " + StringUtils.stringifyException(e));
+    }
+  }
+
+  MonitoredRPCHandler getStatus() {
+    // It is ugly the way we park status up in RpcServer.  Let it be for now.  TODO.
+    MonitoredRPCHandler status = RpcServer.MONITORED_RPC.get();
+    if (status != null) {
+      return status;
+    }
+    status = TaskMonitor.get().createRPCStatus(Thread.currentThread().getName());
+    status.pause("Waiting for a call");
+    RpcServer.MONITORED_RPC.set(status);
+    return status;
+  }
+}

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/FifoRpcScheduler.java

@@ -24,6 +24,7 @@ import java.io.IOException;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
+import org.apache.hadoop.hbase.ipc.CallRunner;
 
 /**
  * A very simple {@code }RpcScheduler} that serves incoming requests in order.
@@ -65,8 +66,13 @@ public class FifoRpcScheduler implements RpcScheduler {
   }
 
   @Override
-  public void dispatch(RpcServer.CallRunner task) throws IOException, InterruptedException {
+  public void dispatch(final CallRunner task) throws IOException, InterruptedException {
-    executor.submit(task);
+    executor.submit(new Runnable() {
+      @Override
+      public void run() {
+        task.run();
+      }
+    });
   }
 
   @Override

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RequestContext.java

@@ -24,6 +24,7 @@ import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.security.User;
 
 import com.google.protobuf.BlockingService;
+
 import org.apache.hadoop.hbase.util.Bytes;
 import org.cloudera.htrace.Trace;
 
@@ -31,9 +32,9 @@ import java.net.InetAddress;
 
 /**
  * Represents client information (authenticated username, remote address, protocol)
- * for the currently executing request within a RPC server handler thread.  If
+ * for the currently executing request.  If called outside the context of a RPC request, all values
- * called outside the context of a RPC request, all values will be
+ * will be <code>null</code>. The {@link CallRunner} class before it a call and then on
- * <code>null</code>.
+ * its way out, it will clear the thread local.
  */
 @InterfaceAudience.Private
 public class RequestContext {
@@ -146,7 +147,7 @@ public class RequestContext {
     return this.service;
   }
 
-  public boolean isInRequest() {
+  boolean isInRequest() {
     return inRequest;
   }
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcScheduler.java

@@ -57,7 +57,7 @@ public interface RpcScheduler {
    *
    * @param task the request to be dispatched
    */
-  void dispatch(RpcServer.CallRunner task) throws IOException, InterruptedException;
+  void dispatch(CallRunner task) throws IOException, InterruptedException;
 
   /** Retrieves length of the general queue for metrics. */
   int getGeneralQueueLength();

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcSchedulerContext.java

@@ -0,0 +1,39 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase.ipc;
+
+import java.net.InetSocketAddress;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
+@InterfaceAudience.Private
+class RpcSchedulerContext implements RpcScheduler.Context {
+  private final RpcServer rpcServer;
+
+  /**
+   * @param rpcServer
+   */
+  RpcSchedulerContext(final RpcServer rpcServer) {
+    this.rpcServer = rpcServer;
+  }
+
+  @Override
+  public InetSocketAddress getListenerAddress() {
+    return this.rpcServer.getListenerAddress();
+  }
+}

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServer.java

@@ -1,5 +1,4 @@
 /**
- *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -74,7 +73,6 @@ import org.apache.hadoop.hbase.codec.Codec;
 import org.apache.hadoop.hbase.exceptions.RegionMovedException;
 import org.apache.hadoop.hbase.io.ByteBufferOutputStream;
 import org.apache.hadoop.hbase.monitoring.MonitoredRPCHandler;
-import org.apache.hadoop.hbase.monitoring.TaskMonitor;
 import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.protobuf.generated.RPCProtos.CellBlockMeta;
 import org.apache.hadoop.hbase.protobuf.generated.RPCProtos.ConnectionHeader;
@@ -111,9 +109,7 @@ import org.apache.hadoop.security.token.SecretManager.InvalidToken;
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.util.StringUtils;
 import org.cliffc.high_scale_lib.Counter;
-import org.cloudera.htrace.Trace;
 import org.cloudera.htrace.TraceInfo;
-import org.cloudera.htrace.TraceScope;
 import org.codehaus.jackson.map.ObjectMapper;
 
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
@@ -128,7 +124,21 @@ import com.google.protobuf.TextFormat;
 
 /**
  * An RPC server that hosts protobuf described Services.
- * <p>Once was copied from Hadoop to local to fix HBASE-900 but deviated long ago.
+ * 
+ * An RpcServer instance has a {@link Listener} that hosts the socket.  Listener has fixed number
+ * of {@link Reader}s in an ExecutorPool, 10 by default.  The Listener does an accept and then
+ * round robin a Reader is chosen to do the read.  The reader is registered on Selector.  Read does
+ * total read off the channel and the parse from which it makes a Call.  The call is wrapped in a
+ * CallRunner and passed to the scheduler to be run.  Reader goes back to see if more to be done
+ * and loops till done.
+ * 
+ * <p>Scheduler can be variously implemented but default simple scheduler has handlers to which it
+ * has given the queues into which calls (i.e. CallRunner instances) are inserted.  Handlers run
+ * taking from the queue.  They run the CallRunner#run method on each item gotten from queue
+ * and keep taking while the server is up.
+ * 
+ * CallRunner#run executes the call.  When done, asks the included Call to put itself on new
+ * queue for {@link Responder} to pull from and return result to client.
  *
  * @see RpcClient
  */
@@ -171,16 +181,13 @@ public class RpcServer implements RpcServerInterface {
   protected SecretManager<TokenIdentifier> secretManager;
   protected ServiceAuthorizationManager authManager;
 
-  protected static final ThreadLocal<RpcServerInterface> SERVER = new ThreadLocal<RpcServerInterface>();
+  /** This is set to Call object before Handler invokes an RPC and ybdie
-  private volatile boolean started = false;
-
-  /** This is set to Call object before Handler invokes an RPC and reset
    * after the call returns.
    */
   protected static final ThreadLocal<Call> CurCall = new ThreadLocal<Call>();
 
   /** Keeps MonitoredRPCHandler per handler thread. */
-  private static final ThreadLocal<MonitoredRPCHandler> MONITORED_RPC
+  static final ThreadLocal<MonitoredRPCHandler> MONITORED_RPC
       = new ThreadLocal<MonitoredRPCHandler>();
 
   protected final InetSocketAddress isa;
@@ -207,7 +214,22 @@ public class RpcServer implements RpcServerInterface {
   protected final boolean tcpKeepAlive; // if T then use keepalives
   protected final long purgeTimeout;    // in milliseconds
 
-  protected volatile boolean running = true;         // true while server runs
+  /**
+   * This flag is used to indicate to sub threads when they should go down.  When we call
+   * {@link #startThreads()}, all threads started will consult this flag on whether they should
+   * keep going.  It is set to false when {@link #stop()} is called.
+   */
+  volatile boolean running = true;
+
+  /**
+   * This flag is set to true after all threads are up and 'running' and the server is then opened
+   * for business by the calle to {@link #openServer()}.
+   */
+  volatile boolean started = false;
+
+  /**
+   * This is a running count of the size of all outstanding calls by size.
+   */
   protected final Counter callQueueSize = new Counter();
 
   protected final List<Connection> connectionList =
@@ -462,7 +484,7 @@ public class RpcServer implements RpcServerInterface {
     /**
      * If we have a response, and delay is not set, then respond
      * immediately.  Otherwise, do not respond to client.  This is
-     * called the by the RPC code in the context of the Handler thread.
+     * called by the RPC code in the context of the Handler thread.
      */
     public synchronized void sendResponseIfReady() throws IOException {
       if (!this.delayResponse) {
@@ -643,8 +665,6 @@ public class RpcServer implements RpcServerInterface {
     @Override
     public void run() {
       LOG.info(getName() + ": starting");
-      SERVER.set(RpcServer.this);
-
       while (running) {
         SelectionKey key = null;
         try {
@@ -815,7 +835,6 @@ public class RpcServer implements RpcServerInterface {
     @Override
     public void run() {
       LOG.info(getName() + ": starting");
-      SERVER.set(RpcServer.this);
       try {
         doRunLoop();
       } finally {
@@ -1685,8 +1704,7 @@ public class RpcServer implements RpcServerInterface {
       Call call = new Call(id, this.service, md, header, param, cellScanner, this, responder,
               totalRequestSize,
               traceInfo);
-      callQueueSize.add(totalRequestSize);
+      scheduler.dispatch(new CallRunner(RpcServer.this, call));
-      scheduler.dispatch(new CallRunner(call));
     }
 
     private boolean authorizeConnection() throws IOException {
@@ -1755,107 +1773,6 @@ public class RpcServer implements RpcServerInterface {
     }
   }
 
-  /**
-   * The real request processing logic, which is usually executed in
-   * thread pools provided by an {@link RpcScheduler}.
-   */
-  class CallRunner implements Runnable {
-    private final Call call;
-
-    public CallRunner(Call call) {
-      this.call = call;
-    }
-
-    public Call getCall() {
-      return call;
-    }
-
-    @Override
-    public void run() {
-      MonitoredRPCHandler status = getStatus();
-      SERVER.set(RpcServer.this);
-      try {
-        status.setStatus("Setting up call");
-        status.setConnection(call.connection.getHostAddress(), call.connection.getRemotePort());
-        if (LOG.isDebugEnabled()) {
-          UserGroupInformation remoteUser = call.connection.user;
-          LOG.debug(call.toShortString() + " executing as " +
-              ((remoteUser == null) ? "NULL principal" : remoteUser.getUserName()));
-        }
-        Throwable errorThrowable = null;
-        String error = null;
-        Pair<Message, CellScanner> resultPair = null;
-        CurCall.set(call);
-        TraceScope traceScope = null;
-        try {
-          if (!started) {
-            throw new ServerNotRunningYetException("Server is not running yet");
-          }
-          if (call.tinfo != null) {
-            traceScope = Trace.startSpan(call.toTraceString(), call.tinfo);
-          }
-          RequestContext.set(User.create(call.connection.user), getRemoteIp(),
-            call.connection.service);
-          // make the call
-          resultPair = call(call.service, call.md, call.param, call.cellScanner, call.timestamp,
-              status);
-        } catch (Throwable e) {
-          LOG.debug(Thread.currentThread().getName() + ": " + call.toShortString(), e);
-          errorThrowable = e;
-          error = StringUtils.stringifyException(e);
-        } finally {
-          if (traceScope != null) {
-            traceScope.close();
-          }
-          // Must always clear the request context to avoid leaking
-          // credentials between requests.
-          RequestContext.clear();
-        }
-        CurCall.set(null);
-        callQueueSize.add(call.getSize() * -1);
-        // Set the response for undelayed calls and delayed calls with
-        // undelayed responses.
-        if (!call.isDelayed() || !call.isReturnValueDelayed()) {
-          Message param = resultPair != null ? resultPair.getFirst() : null;
-          CellScanner cells = resultPair != null ? resultPair.getSecond() : null;
-          call.setResponse(param, cells, errorThrowable, error);
-        }
-        call.sendResponseIfReady();
-        status.markComplete("Sent response");
-        status.pause("Waiting for a call");
-      } catch (OutOfMemoryError e) {
-        if (errorHandler != null) {
-          if (errorHandler.checkOOME(e)) {
-            LOG.info(Thread.currentThread().getName() + ": exiting on OutOfMemoryError");
-            return;
-          }
-        } else {
-          // rethrow if no handler
-          throw e;
-        }
-      } catch (ClosedChannelException cce) {
-        LOG.warn(Thread.currentThread().getName() + ": caught a ClosedChannelException, " +
-            "this means that the server was processing a " +
-            "request but the client went away. The error message was: " +
-            cce.getMessage());
-      } catch (Exception e) {
-        LOG.warn(Thread.currentThread().getName()
-            + ": caught: " + StringUtils.stringifyException(e));
-      }
-    }
-
-    public MonitoredRPCHandler getStatus() {
-      MonitoredRPCHandler status = MONITORED_RPC.get();
-      if (status != null) {
-        return status;
-      }
-      status = TaskMonitor.get().createRPCStatus(Thread.currentThread().getName());
-      status.pause("Waiting for a call");
-      MONITORED_RPC.set(status);
-      return status;
-    }
-  }
-
   /**
    * Datastructure for passing a {@link BlockingService} and its associated class of
    * protobuf service interface.  For example, a server that fielded what is defined
@@ -1878,14 +1795,6 @@ public class RpcServer implements RpcServerInterface {
     }
   }
 
-  private class RpcSchedulerContextImpl implements RpcScheduler.Context {
-
-    @Override
-    public InetSocketAddress getListenerAddress() {
-      return RpcServer.this.getListenerAddress();
-    }
-  }
-
   /**
    * Constructs a server listening on the named port and address.
    * @param serverInstance hosting instance of {@link Server}. We will do authentications if an
@@ -1938,7 +1847,7 @@ public class RpcServer implements RpcServerInterface {
       HBaseSaslRpcServer.init(conf);
     }
     this.scheduler = scheduler;
-    this.scheduler.init(new RpcSchedulerContextImpl());
+    this.scheduler.init(new RpcSchedulerContext(this));
   }
 
   /**
@@ -1995,7 +1904,12 @@ public class RpcServer implements RpcServerInterface {
    */
   @Override
   public void openServer() {
-    started = true;
+    this.started = true;
+  }
+
+  @Override
+  public boolean isStarted() {
+    return this.started;
   }
 
   /**
@@ -2018,6 +1932,8 @@ public class RpcServer implements RpcServerInterface {
 
   @Override
   public void refreshAuthManager(PolicyProvider pp) {
+    // Ignore warnings that this should be accessed in a static way instead of via an instance;
+    // it'll break if you go via static route.
     this.authManager.refresh(this.conf, pp);
   }
 
@@ -2199,6 +2115,11 @@ public class RpcServer implements RpcServerInterface {
     this.errorHandler = handler;
   }
 
+  @Override
+  public HBaseRPCErrorHandler getErrorHandler() {
+    return this.errorHandler;
+  }
+
   /**
    * Returns the metrics instance for reporting RPC call statistics
    */
@@ -2206,6 +2127,11 @@ public class RpcServer implements RpcServerInterface {
     return metrics;
   }
 
+  @Override
+  public void addCallSize(final long diff) {
+    this.callQueueSize.add(diff);
+  }
+
   /**
    * Authorize the incoming client connection.
    *
@@ -2376,7 +2302,7 @@ public class RpcServer implements RpcServerInterface {
    */
   public static InetAddress getRemoteIp() {
     Call call = CurCall.get();
-    if (call != null) {
+    if (call != null && call.connection.socket != null) {
       return call.connection.socket.getInetAddress();
     }
     return null;
@@ -2394,17 +2320,6 @@ public class RpcServer implements RpcServerInterface {
     return null;
   }
 
-  /**
-   * May be called under
-   * {@code #call(Class, RpcRequestBody, long, MonitoredRPCHandler)} implementations,
-   * and under protobuf methods of parameters and return values.
-   * Permits applications to access the server context.
-   * @return the server instance called under or null
-   */
-  public static RpcServerInterface get() {
-    return SERVER.get();
-  }
-
   /**
    * A convenience method to bind to a given address and report
    * better exceptions if the address is not a valid host.

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServerInterface.java

@@ -34,18 +34,24 @@ import com.google.protobuf.Descriptors.MethodDescriptor;
 import com.google.protobuf.Message;
 import com.google.protobuf.ServiceException;
 
+/**
+ * RpcServer Interface.
+ * Start calls {@link #openServer()} and then {@link #startThreads()}.  Prefer {@link #start()}
+ * and {@link #stop()}.  Only use {@link #openServer()} and {@link #startThreads()} if in a
+ * situation where you could start getting requests though the server not up and fully
+ * initiaalized.
+ */
 @InterfaceAudience.Private
 public interface RpcServerInterface {
-  // TODO: Needs cleanup.  Why a 'start', and then a 'startThreads' and an 'openServer'?
-
-  void setSocketSendBufSize(int size);
-
   void start();
+  void openServer();
+  void startThreads();
+  boolean isStarted();
 
   void stop();
-
   void join() throws InterruptedException;
 
+  void setSocketSendBufSize(int size);
   InetSocketAddress getListenerAddress();
 
   Pair<Message, CellScanner> call(BlockingService service, MethodDescriptor md,
@@ -53,10 +59,7 @@ public interface RpcServerInterface {
   throws IOException, ServiceException;
 
   void setErrorHandler(HBaseRPCErrorHandler handler);
-
+  HBaseRPCErrorHandler getErrorHandler();
-  void openServer();
-
-  void startThreads();
 
   /**
    * Returns the metrics instance for reporting RPC call statistics
@@ -64,7 +67,14 @@ public interface RpcServerInterface {
   MetricsHBaseServer getMetrics();
 
   /**
-   * Refresh autentication manager policy.
+   * Add/subtract from the current size of all outstanding calls.  Called on setup of a call to add
+   * call total size and then again at end of a call to remove the call size.
+   * @param diff Change (plus or minus)
+   */
+  void addCallSize(long diff);
+
+  /**
+   * Refresh authentication manager policy.
    * @param pp
    */
   @VisibleForTesting

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleRpcScheduler.java

@@ -42,9 +42,9 @@ public class SimpleRpcScheduler implements RpcScheduler {
   private final int priorityHandlerCount;
   private final int replicationHandlerCount;
   private final PriorityFunction priority;
-  final BlockingQueue<RpcServer.CallRunner> callQueue;
+  final BlockingQueue<CallRunner> callQueue;
-  final BlockingQueue<RpcServer.CallRunner> priorityCallQueue;
+  final BlockingQueue<CallRunner> priorityCallQueue;
-  final BlockingQueue<RpcServer.CallRunner> replicationQueue;
+  final BlockingQueue<CallRunner> replicationQueue;
   private volatile boolean running = false;
   private final List<Thread> handlers = Lists.newArrayList();
 
@@ -73,12 +73,12 @@ public class SimpleRpcScheduler implements RpcScheduler {
     this.replicationHandlerCount = replicationHandlerCount;
     this.priority = priority;
     this.highPriorityLevel = highPriorityLevel;
-    this.callQueue = new LinkedBlockingQueue<RpcServer.CallRunner>(maxQueueLength);
+    this.callQueue = new LinkedBlockingQueue<CallRunner>(maxQueueLength);
     this.priorityCallQueue = priorityHandlerCount > 0
-        ? new LinkedBlockingQueue<RpcServer.CallRunner>(maxQueueLength)
+        ? new LinkedBlockingQueue<CallRunner>(maxQueueLength)
         : null;
     this.replicationQueue = replicationHandlerCount > 0
-        ? new LinkedBlockingQueue<RpcServer.CallRunner>(maxQueueLength)
+        ? new LinkedBlockingQueue<CallRunner>(maxQueueLength)
         : null;
   }
 
@@ -101,7 +101,7 @@ public class SimpleRpcScheduler implements RpcScheduler {
 
   private void startHandlers(
       int handlerCount,
-      final BlockingQueue<RpcServer.CallRunner> callQueue,
+      final BlockingQueue<CallRunner> callQueue,
       String threadNamePrefix) {
     for (int i = 0; i < handlerCount; i++) {
       Thread t = new Thread(new Runnable() {
@@ -126,7 +126,7 @@ public class SimpleRpcScheduler implements RpcScheduler {
   }
 
   @Override
-  public void dispatch(RpcServer.CallRunner callTask) throws InterruptedException {
+  public void dispatch(CallRunner callTask) throws InterruptedException {
     RpcServer.Call call = callTask.getCall();
     int level = priority.getPriority(call.header, call.param);
     if (priorityCallQueue != null && level > highPriorityLevel) {
@@ -153,10 +153,10 @@ public class SimpleRpcScheduler implements RpcScheduler {
     return replicationQueue == null ? 0 : replicationQueue.size();
   }
 
-  private void consumerLoop(BlockingQueue<RpcServer.CallRunner> myQueue) {
+  private void consumerLoop(BlockingQueue<CallRunner> myQueue) {
     while (running) {
       try {
-        RpcServer.CallRunner task = myQueue.take();
+        CallRunner task = myQueue.take();
         task.run();
       } catch (InterruptedException e) {
         Thread.interrupted();

hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestCallRunner.java

@@ -0,0 +1,39 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase.ipc;
+
+import org.apache.hadoop.hbase.SmallTests;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+import org.mockito.Mockito;
+
+@Category(SmallTests.class)
+public class TestCallRunner {
+  /**
+   * Does nothing but exercise a {@link CallRunner} outside of {@link RpcServer} context.
+   */
+  @Test
+  public void testSimpleCall() {
+    RpcServerInterface mockRpcServer = Mockito.mock(RpcServerInterface.class);
+    Mockito.when(mockRpcServer.isStarted()).thenReturn(true);
+    RpcServer.Call mockCall = Mockito.mock(RpcServer.Call.class);
+    mockCall.connection = Mockito.mock(RpcServer.Connection.class);
+    CallRunner cr = new CallRunner(mockRpcServer, mockCall);
+    cr.run();
+  }
+}

hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestIPC.java

@@ -286,7 +286,7 @@ public class TestIPC {
         client.call(md, param, CellUtil.createCellScanner(ImmutableList.of(CELL)),
             md.getOutputType().toProto(), User.getCurrent(), rpcServer.getListenerAddress(), 0);
       }
-      verify(scheduler, times(10)).dispatch((RpcServer.CallRunner) anyObject());
+      verify(scheduler, times(10)).dispatch((CallRunner) anyObject());
     } finally {
       rpcServer.stop();
       verify(scheduler).stop();

hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestSimpleRpcScheduler.java

@@ -27,9 +27,7 @@ import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.SmallTests;
 import org.apache.hadoop.hbase.ipc.RpcServer.Call;
-import org.apache.hadoop.hbase.ipc.RpcServer.CallRunner;
 import org.apache.hadoop.hbase.protobuf.generated.RPCProtos;
-import org.apache.hadoop.hbase.regionserver.RegionServerServices;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;