ThreadGroup provides a means of keeping track of a number of threads as a group. A Thread can belong to only one ThreadGroup at a time; adding a thread to a new group will remove it from any previous group.
Newly created threads belong to the same group as the thread from which they were created.
| Default | = | thgroup_default |
Adds the given thread to this group, removing it from any other group to which it may have previously belonged.
puts "Initial group is #{ThreadGroup::Default.list}"
tg = ThreadGroup.new
t1 = Thread.new { sleep }
t2 = Thread.new { sleep }
puts "t1 is #{t1}"
puts "t2 is #{t2}"
tg.add(t1)
puts "Initial group now #{ThreadGroup::Default.list}"
puts "tg group now #{tg.list}"
produces:
Initial group is #<Thread:0x401bdf4c> t1 is #<Thread:0x401b3c90> t2 is #<Thread:0x401b3c18> Initial group now #<Thread:0x401b3c18>#<Thread:0x401bdf4c> tg group now #<Thread:0x401b3c90>
Prevents threads from being added to or removed from the receiving ThreadGroup. New threads can still be started in an enclosed ThreadGroup.
ThreadGroup::Default.enclose #=> #<ThreadGroup:0x4029d914>
thr = Thread::new { Thread.stop } #=> #<Thread:0x402a7210 sleep>
tg = ThreadGroup::new #=> #<ThreadGroup:0x402752d4>
tg.add thr
produces:
ThreadError: can't move from the enclosed thread group
Returns an array of all existing Thread objects that belong to this group.
ThreadGroup::Default.list #=> [#<Thread:0x401bdf4c run>]