inspect outgoing packets and delay them, with jpcap

Question

I can read the content of the packets, but I don't know how to delay them.

(I am not fluent in English.)

Answer 1

Packet capture doesn't allow you to prevent a packet being sent. It is for monitoring only. If you want to delay a packet you need a device eg a multi-homed PC, to sit between your system and rest of the network. This can be used to capture on one network interface and copy packets to a second interface with what ever delay you want.

If you want to do this in software you can create a TCP proxy server and have your software connect to it.