title: Multiple clients access the server concurrently
body: <p>I am having a login screen and now say we have 2 users with username:amit and ajay and their password: "pass" and "word".Now i want that suppose their are two desktop applications open on same system.I want that multiple clients access the server concurrently.</p>
  
  <p>Meaning say in one login screen amit enters the username and then his thread should sleep and in second login screen let ajay enter his username then amit will again enter his password after that ajay enter his password.How to do it in java?Please help .</p>