Remove hedged rpc call support, implement the logic in MaterRegistry …

…directly

hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/AbstractRpcClient.java

@@ -20,12 +20,12 @@
 
 import static org.apache.hadoop.hbase.ipc.IPCUtil.toIOE;
 import static org.apache.hadoop.hbase.ipc.IPCUtil.wrapException;
+
 import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 import java.net.UnknownHostException;
 import java.util.Collection;
-import java.util.Set;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ScheduledFuture;
@@ -47,6 +47,7 @@
 import org.apache.yetus.audience.InterfaceAudience;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+
 import org.apache.hbase.thirdparty.com.google.common.annotations.VisibleForTesting;
 import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
 import org.apache.hbase.thirdparty.com.google.common.cache.CacheBuilder;
@@ -60,6 +61,7 @@
 import org.apache.hbase.thirdparty.com.google.protobuf.RpcController;
 import org.apache.hbase.thirdparty.com.google.protobuf.ServiceException;
 import org.apache.hbase.thirdparty.io.netty.util.HashedWheelTimer;
+
 import org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos;
 
 /**
@@ -512,13 +514,6 @@ public RpcChannel createRpcChannel(ServerName sn, User user, int rpcTimeout)
     return new RpcChannelImplementation(this, createAddr(sn), user, rpcTimeout);
   }
 
-  @Override
-  public RpcChannel createHedgedRpcChannel(Set<ServerName> sns, User user, int rpcTimeout)
-      throws UnknownHostException {
-    // Check HedgedRpcChannel implementation for detailed comments.
-    throw new UnsupportedOperationException("Hedging not supported for this implementation.");
-  }
-
   private static class AbstractRpcChannel {
 
     protected final InetSocketAddress addr;

hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/NettyRpcClient.java

@@ -18,20 +18,14 @@
 package org.apache.hadoop.hbase.ipc;
 
 import java.io.IOException;
-import java.net.InetSocketAddress;
 import java.net.SocketAddress;
-import java.net.UnknownHostException;
-import java.util.HashSet;
-import java.util.Set;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.client.MetricsConnection;
-import org.apache.hadoop.hbase.security.User;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.hbase.thirdparty.com.google.protobuf.RpcChannel;
+
 import org.apache.hbase.thirdparty.io.netty.channel.Channel;
 import org.apache.hbase.thirdparty.io.netty.channel.EventLoopGroup;
 import org.apache.hbase.thirdparty.io.netty.channel.nio.NioEventLoopGroup;
@@ -82,19 +76,6 @@ protected NettyRpcConnection createConnection(ConnectionId remoteId) throws IOEx
     return new NettyRpcConnection(this, remoteId);
   }
 
-  @Override
-  public RpcChannel createHedgedRpcChannel(Set<ServerName> sns, User user, int rpcTimeout)
-      throws UnknownHostException {
-    final int hedgedRpcFanOut = conf.getInt(HConstants.HBASE_RPCS_HEDGED_REQS_FANOUT_KEY,
-        HConstants.HBASE_RPCS_HEDGED_REQS_FANOUT_DEFAULT);
-    Set<InetSocketAddress> addresses = new HashSet<>();
-    for (ServerName sn: sns) {
-      addresses.add(createAddr(sn));
-    }
-    return new HedgedRpcChannel(this, addresses, user, rpcTimeout,
-        hedgedRpcFanOut);
-  }
-
   @Override
   protected void closeInternal() {
     if (shutdownGroupWhenClose) {

hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcClient.java

@@ -19,10 +19,10 @@
 
 import java.io.Closeable;
 import java.io.IOException;
-import java.util.Set;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.security.User;
 import org.apache.yetus.audience.InterfaceAudience;
+
 import org.apache.hbase.thirdparty.com.google.protobuf.BlockingRpcChannel;
 import org.apache.hbase.thirdparty.com.google.protobuf.RpcChannel;
 
@@ -82,16 +82,6 @@ BlockingRpcChannel createBlockingRpcChannel(ServerName sn, User user, int rpcTim
   RpcChannel createRpcChannel(final ServerName sn, final User user, int rpcTimeout)
       throws IOException;
 
-  /**
-   * Creates a channel that can hedge request to multiple underlying channels.
-   * @param sns  Set of servers for underlying channels.
-   * @param user user for the connection.
-   * @param rpcTimeout rpc timeout to use.
-   * @return A hedging rpc channel for this rpc client instance.
-   */
-  RpcChannel createHedgedRpcChannel(final Set<ServerName> sns, final User user, int rpcTimeout)
-       throws IOException;
-
   /**
    * Interrupt the connections to the given server. This should be called if the server
    * is known as actually dead. This will not prevent current operation to be retried, and,