Whichever one you have available. If you are using eclipse or Netbeans then they both include built in visual debuggers. If you are using command line tools then jdb. You can find lots of useful information on Java in general starting at the Java Tutorials[^].
One of these days I'm going to think of a really clever signature.
I am making a Web site in which i want to capture Sound from Client side & then send 10 sec Audio to Server.
I researched & get two things,
1) To use flash based Audio recorder
2) To use Applet
so kindly help in this using both Approach.