HDDS-15154. Remove unused RPC code

hadoop-hdds/common/src/main/java/org/apache/hadoop/ipc_/Client.java

@@ -1303,15 +1303,6 @@ public Client(Class<? extends Writable> valueClass, Configuration conf,
         CommonConfigurationKeys.IPC_CLIENT_ASYNC_CALLS_MAX_DEFAULT);
   }
 
-  /**
-   * Construct an IPC client with the default SocketFactory.
-   * @param valueClass input valueClass.
-   * @param conf input Configuration.
-   */
-  public Client(Class<? extends Writable> valueClass, Configuration conf) {
-    this(valueClass, conf, NetUtils.getDefaultSocketFactory(conf));
-  }
-
   @Override
   public String toString() {
     return getClass().getSimpleName() + "-"

hadoop-hdds/common/src/main/java/org/apache/hadoop/ipc_/ProtoUtil.java

@@ -18,9 +18,6 @@
 
 package org.apache.hadoop.ipc_;
 
-import java.io.DataInput;
-import java.io.IOException;
-
 import org.apache.hadoop.ipc_.protobuf.IpcConnectionContextProtos.IpcConnectionContextProto;
 import org.apache.hadoop.ipc_.protobuf.IpcConnectionContextProtos.UserInformationProto;
 import org.apache.hadoop.ipc_.protobuf.RpcHeaderProtos.*;
@@ -31,47 +28,7 @@
 
 public abstract class ProtoUtil {
 
-  /**
-   * Read a variable length integer in the same format that ProtoBufs encodes.
-   * @param in the input stream to read from
-   * @return the integer
-   * @throws IOException if it is malformed or EOF.
-   */
-  public static int readRawVarint32(DataInput in) throws IOException {
-    byte tmp = in.readByte();
-    if (tmp >= 0) {
-      return tmp;
-    }
-    int result = tmp & 0x7f;
-    if ((tmp = in.readByte()) >= 0) {
-      result |= tmp << 7;
-    } else {
-      result |= (tmp & 0x7f) << 7;
-      if ((tmp = in.readByte()) >= 0) {
-        result |= tmp << 14;
-      } else {
-        result |= (tmp & 0x7f) << 14;
-        if ((tmp = in.readByte()) >= 0) {
-          result |= tmp << 21;
-        } else {
-          result |= (tmp & 0x7f) << 21;
-          result |= (tmp = in.readByte()) << 28;
-          if (tmp < 0) {
-            // Discard upper 32 bits.
-            for (int i = 0; i < 5; i++) {
-              if (in.readByte() >= 0) {
-                return result;
-              }
-            }
-            throw new IOException("Malformed varint");
-          }
-        }
-      }
-    }
-    return result;
-  }
 
-
   /** 
    * This method creates the connection context  using exactly the same logic
    * as the old connection context as was done for writable where

hadoop-hdds/common/src/main/java/org/apache/hadoop/ipc_/ProtobufRpcEngine.java

@@ -65,32 +65,6 @@ public static AsyncGet<Message, Exception> getAsyncReturnMessage() {
     return ASYNC_RETURN_MESSAGE.get();
   }
 
-  @Override
-  @SuppressWarnings("unchecked")
-  public <T> ProtocolProxy<T> getProxy(Class<T> protocol, long clientVersion,
-      ConnectionId connId, Configuration conf, SocketFactory factory)
-      throws IOException {
-    final Invoker invoker = new Invoker(protocol, connId, conf, factory);
-    return new ProtocolProxy<T>(protocol, (T) Proxy.newProxyInstance(
-        protocol.getClassLoader(), new Class[] {protocol}, invoker));
-  }
-
-  public <T> ProtocolProxy<T> getProxy(Class<T> protocol, long clientVersion,
-      InetSocketAddress addr, UserGroupInformation ticket, Configuration conf,
-      SocketFactory factory, int rpcTimeout) throws IOException {
-    return getProxy(protocol, clientVersion, addr, ticket, conf, factory,
-        rpcTimeout, null);
-  }
-
-  @Override
-  public <T> ProtocolProxy<T> getProxy(Class<T> protocol, long clientVersion,
-      InetSocketAddress addr, UserGroupInformation ticket, Configuration conf,
-      SocketFactory factory, int rpcTimeout, RetryPolicy connectionRetryPolicy
-      ) throws IOException {
-    return getProxy(protocol, clientVersion, addr, ticket, conf, factory,
-      rpcTimeout, connectionRetryPolicy, null, null);
-  }
-
   @Override
   @SuppressWarnings("unchecked")
   public <T> ProtocolProxy<T> getProxy(Class<T> protocol, long clientVersion,
@@ -309,22 +283,6 @@ public ConnectionId getConnectionId() {
       return remoteId;
     }
 
-    protected long getClientProtocolVersion() {
-      return clientProtocolVersion;
-    }
-
-    protected String getProtocolName() {
-      return protocolName;
-    }
-  }
-
-  static Client getClient(Configuration conf) {
-    return CLIENTS.getClient(conf, SocketFactory.getDefault(),
-        RpcWritable.Buffer.class);
-  }
-
-  public static void clearClientCache() {
-    CLIENTS.clearCache();
   }
 
   @Override
@@ -556,6 +514,7 @@ static class RpcProtobufRequest extends RpcWritable.Buffer {
     private volatile RequestHeaderProto requestHeader;
     private Message payload;
 
+    @SuppressWarnings("unused") // required for Server#procesRpcRequest
     public RpcProtobufRequest() {
     }