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daemon thread.

jaman tai
Ranch Hand

Joined: Sep 26, 2005
Posts: 37
With respect to User and Daemon threads:

a) Daemon threads can not be destroyed

b) Running User threads prevent a JVM from terminating program

c) Running Daemon threads prevent a Java VM from terminating program

d) Daemon threads can not be grouped together

e) The JVM can terminate program when only daemon threads are running

answer: b, e? why e is correct?
Pranav Shukla
Ranch Hand

Joined: Oct 05, 2005
Posts: 64
Daemon threads exist only to serve User threads. Typically they will provide services to the User Threads and User Threads will do the real "work" in the program.

So if there doesn't exist any live User Thread, the JVM may choose to terminate the program even if there are daemon threads running.


Pranav Shukla
SCJP, SCWCD, SCBCD
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
You can find out why e is correct by looking up the definition of a Daemon thread.


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subject: daemon thread.