Event objects. : Synchronize « Thread « Python Tutorial

1. Python Tutorial
2. Thread
3. Synchronize

import threading
import random
import time

class VehicleThread( threading.Thread ):
   def __init__( self, threadName, event ):
      threading.Thread.__init__( self, name = threadName )
      self.threadEvent = event
      
   def run( self ):
      time.sleep( random.randrange( 1, 10 ) )
      print "%s arrived at %s" % ( self.getName(), time.ctime( time.time() ) )

      self.threadEvent.wait()

      print "%s passes through intersection at %s" % ( self.getName(), time.ctime( time.time() ) )

greenLight = threading.Event()
vehicleThreads = []

for i in range( 1, 11 ):
   vehicleThreads.append( VehicleThread( "Vehicle" + str( i ),greenLight ) )

for vehicle in vehicleThreads:
   vehicle.start()

while threading.activeCount() > 1:
   greenLight.clear()
   print "RED LIGHT! at", time.ctime( time.time() )
   time.sleep( 3 )

   print "GREEN LIGHT! at", time.ctime( time.time() )
   greenLight.set()
   time.sleep( 1 )