title: Intercept and block connection whit Java like a firewall
body: <p>I have an question:</p>
  
  <p>How i can intercept the connection (For example from IP Adress: 100.100.100.101) and block it, like a firewall?</p>
  
  <p>I dont have any idea where to start.</p>
  
  <p>I think about ServerSocket but just work in a current socket.</p>
  
  <p>Thanks for read the question.
  Have a good night.</p>