public MasterAdminServer(FlumeMaster master, FlumeConfiguration config) throws IOException { Preconditions.checkArgument(master != null, "FlumeConfigMaster is null in MasterAdminServer!"); this.master = master; String rpcType = config.getMasterHeartbeatRPC(); this.stubServer = null; if (FlumeConfiguration.RPC_TYPE_AVRO.equals(rpcType)) { stubServer = new MasterAdminServerAvro(this); } else { throw new IOException("No valid RPC framework specified in config"); } }