第一种方式：

import tornado.ioloop

import tornado.web

from tornado import gen

from tornado.concurrent import Future

import time

#########异步效果1，iploop

class MainHandler(tornado.web.RequestHandler):

@gen.coroutine##加一个装饰器

def get(self):

import time

###等待五秒种

future=Future()

self.write('hello,world ')

##五秒钟的超时时间，

tornado.ioloop.IOLoop.current().add_timeout(time.time()+,self.doing)##等待五秒的时间

yield future

def doing(self,*args,**kwargs):

self.write('yibu ')

self.finish()

class IndexHandler(tornado.web.RequestHandler):

def get(self):

self.write('index')

##下面是路由映射

appliaction=tornado.web.Application([

(r'/main',MainHandler),

(r'/index', IndexHandler),

])

第二种方式：

import tornado.ioloop

import tornado.web

from tornado import gen

from tornado.concurrent import Future

import time

######异步效果2，AsyncHTTPClient

class MainHandler(tornado.web.RequestHandler):

@gen.coroutine##加一个装饰器

def get(self):

import time

from tornado import httpclient

http=httpclient.AsyncHTTPClient()

yield http.fetch('http://www.geogle.com',self.doing )

def doing(self,*args,**kwargs):

self.write('yibu ')

self.finish()

class IndexHandler(tornado.web.RequestHandler):

def get(self):

self.write('index')

##下面是路由映射

appliaction=tornado.web.Application([

(r'/main',MainHandler),

(r'/index', IndexHandler),

])

##settings配置

if __name__ == '__main__':

appliaction.listen()

tornado.ioloop.IOLoop.instance().start()

第三种方式：

import tornado.ioloop

import tornado.web

from tornado import gen

from tornado.concurrent import Future

import time

#异步效果3，future

future=None

class MainHandler(tornado.web.RequestHandler):

@gen.coroutine##加一个装饰器

def get(self):

import time

global future

future=Future()

future.add_done_callback(self.doing)#####在这里设置返回值，future，当future里面的result值发生改变的时候就会触发这个的执行

yield future

def doing(self,*args,**kwargs):

self.write('yibu ')

self.finish()

class IndexHandler(tornado.web.RequestHandler):

def get(self):

global future

future.set_result(None)##设置返回值

self.write('index')

##下面是路由映射

appliaction=tornado.web.Application([

(r'/main',MainHandler),

(r'/index', IndexHandler),

])

##settings配置

if __name__ == '__main__':

appliaction.listen()

tornado.ioloop.IOLoop.instance().start()