def add_connection(uri) #:nodoc:
      publisher = SlaveProxy.new(@caller_id, uri)
      begin
        protocol, host, port = publisher.request_topic(@topic_name, [["TCPROS"]])
        if protocol == "TCPROS"
          connection = TCPROS::Client.new(host, port, @caller_id, @topic_name, @topic_type, uri, @tcp_no_delay)
          connection.start
        else
          puts "not support protocol: #{protocol}"
          raise "not support protocol: #{protocol}"
        end
        connection.id = "#{@topic_name}_in_#{@connection_id_number}"
        @connection_id_number += 1
        @connections.push(connection)
        return connection
      rescue
#	puts "request to #{uri} fail"
        return false
      end
    end
def add_connection(uri) #:nodoc:
      publisher = SlaveProxy.new(@caller_id, uri)
      begin
        protocol, host, port = publisher.request_topic(@topic_name, [["TCPROS"]])
        if protocol == "TCPROS"
          connection = TCPROS::Client.new(host, port, @caller_id, @topic_name, @topic_type, uri, @tcp_no_delay)
          connection.start
        else
          puts "not support protocol: #{protocol}"
          raise "not support protocol: #{protocol}"
        end
        connection.id = "#{@topic_name}_in_#{@connection_id_number}"
        @connection_id_number += 1
        @connections.push(connection)
        return connection
      rescue
#	puts "request to #{uri} fail"
        return false
      end
    end
request topic to master and start connection with publisher.
 @param [String] uri uri to connect
 @return [TCPROS::Client] new connection