about threads

this is my interview questionwe can find a thread is alive or not using .isAlive() method.my problem is how can we get no of threads which are alive at present?is there any method is avilabel for this?
[229 byte] By [ramireddia] at [2007-10-3 4:56:36]
# 1
Read about ThreadGroup.Kaj
kajbja at 2007-7-14 23:01:51 > top of Java-index,Java Essentials,Java Programming...
# 2
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/ThreadGroup.html
kajbja at 2007-7-14 23:01:51 > top of Java-index,Java Essentials,Java Programming...
# 3
thanx kajbj
ramireddia at 2007-7-14 23:01:51 > top of Java-index,Java Essentials,Java Programming...