I want to do a project in Java for creating an firewall by using ome efficient algorithms..Please kindly
reply me the source code for the firewall in Java.

Currently we don't have a java code for firewall applications , what we can do is to give you hints , first you will need to have a good knowledge of java socket programming and java NIO package .
Example on NIO programming :


Also example on firewall software but not IN java ,which is should help you :