python内存释放原则

def getInit(class_name):
 """动态加载模块"""
 resultmodule = __import__(class_name, globals(), locals(), [class_name])
 resultclass = getattr(resultmodule, class_name)
 return resultclass()
import threading, time
 
class b:
 def __init__(self, *args, **kwargs): 
 self.name = "b"
 self.class_name = "a"
 print "%s is inited" % (self.name)
 
 def __del__(self):
 print "%s is deleted" % (self.name)
 
 def other_run(self, obj=None):
 if obj:
 obj.run()
 
 def run(self, *args, **kwargs):
 obj = getInit(self.class_name)
 obj.run()
 self.other_run(obj) 
 print "%s is run" % (self.name)
 
def treading():
 n = 0
 c = b()
 while n<2:
 n += 1
 print "
"
 print "start"
 c.run()
 print "end"
 print "
"
 
if __name__ == '__main__':
 param = {}
 th = threading.Thread(target = treading, args = ())
 th.start()
 
exit()

b is inited
start
a is inited
a is run
a is run
b is run
a is deleted
end
start
a is inited
a is run
a is run
b is run
a is deleted
end
b is deleted

def getInit(class_name):
 resultmodule = __import__(class_name, globals(), locals(), [class_name])
 resultclass = getattr(resultmodule, class_name)
 return resultclass()
import threading, time
import a
 
class b:
 def __init__(self, *args, **kwargs): 
 self.name = "b"
 self.class_name = "a"
 self.obj = getInit(self.class_name)
 print "%s is inited" % (self.name)
 
 def __del__(self):
 print "%s is deleted" % (self.name)
 
 def other_run(self):
 if self.obj:
 self.obj.run()
 
 def run(self, *args, **kwargs):
 self.obj.run()
 self.other_run() 
 print "%s is run" % (self.name)
 
def treading():
 n = 0
 c = b()
 while n<2:
 n += 1
 print "
"
 print "start"
 c.run()
 print "end"
 print "
"
 
if __name__ == '__main__':
 param = {}
 th = threading.Thread(target = treading, args = ())
 th.start()
 
exit()

a is inited
b is inited
start
a is run
a is run
b is run
end
start
a is run
a is run
b is run
end
b is deleted
a is deleted