code: @ManagedOperation(description="Prints the send and receive buffers")
      public String printBuffers() {
          StringBuilder sb=new StringBuilder("\n");
          synchronized(this) {
              for(Map.Entry<Address,Connection> entry: conns.entrySet()) {
                  NioConnection val=(NioConnection)entry.getValue();
                  sb.append(entry.getKey()).append(":\n  ").append("recv_buf: ").append(val.recv_buf)
                    .append("\n  send_buf: ").append(val.send_buf).append("\n");
              }
          }
          return sb.toString();
      }
docs: Prints send and receive buffers for all connections