Python kill process

import os
import threading
import time
import subprocess

class R(threading.Thread):
    def __init__(self, cmd):
        threading.Thread.__init__(self)
        self.cmd = cmd
        self.flag = False
        self.pro = subprocess.Popen(self.cmd)
        
    def setFlag(self, f):
        self.flag = f

    def run(self):
        while True:
            if self.pro == None:
                break
            elif self.flag:
                self.pro.kill()
                break
        
def p(cmd):
    #t = os.popen(cmd).read()
    t = subprocess.Popen(['java', 'T'])
    print t
    
def f():
    t1 = time.time()
    print '0000000000'
    t = threading.Thread(target=p, args=('java T',))
    t.start()
    print '1111111111'
    time.sleep(2)
    t2 = time.time()
    t0 = t2 - t1    

def f2():
    cmd = ['java', 'T']
    r = R(cmd)
    r.start()
    time.sleep(2)
    r.setFlag(True)

if __name__ == '__main__':
    f2()