python 实现敏感词过滤的方法

#!/usr/bin/python2.6  
# -*- coding: utf-8 -*- 
import time 
class Node(object): 
  def __init__(self): 
    self.children = None 
 
# The encode of word is UTF-8 
def add_word(root,word): 
  node = root 
  for i in range(len(word)): 
    if node.children == None: 
      node.children = {} 
      node.children[word[i]] = Node() 
 
    elif word[i] not in node.children: 
      node.children[word[i]] = Node() 
 
    node = node.children[word[i]] 
 
def init(path): 
  root = Node() 
  fp = open(path,'r') 
  for line in fp: 
    line = line[0:-1] 
    #print len(line) 
    #print line 
    #print type(line) 
    add_word(root,line) 
  fp.close() 
  return root 
 
# The encode of word is UTF-8 
# The encode of message is UTF-8 
def is_contain(message, root): 
  for i in range(len(message)): 
    p = root 
    j = i 
    while (j<len(message) and p.children!=None and message[j] in p.children): 
      p = p.children[message[j]] 
      j = j + 1 
 
    if p.children==None: 
      #print '---word---',message[i:j] 
      return True 
   
  return False 
 
 
 
def dfa(): 
  print '----------------dfa-----------' 
  root = init('/tmp/word.txt') 
 
  message = '四处乱咬乱吠，吓得家中11岁的女儿躲在屋里不敢出来，直到辖区派出所民警赶到后，才将孩子从屋中救出。最后在征得主人同意后，民警和村民合力将这只发疯的狗打死' 
  #message = '不顾' 
  print '***message***',len(message) 
  start_time = time.time() 
  for i in range(1000): 
    res = is_contain(message,root) 
    #print res 
  end_time = time.time() 
  print (end_time - start_time)  
 
def is_contain2(message,word_list): 
  for item in word_list: 
    if message.find(item)!=-1: 
      return True 
  return False 
 
def normal(): 
  print '------------normal--------------' 
  path = '/tmp/word.txt' 
  fp = open(path,'r') 
  word_list = [] 
  message = '四处乱咬乱吠，吓得家中11岁的女儿躲在屋里不敢出来，直到辖区派出所民警赶到后，才将孩子从屋中救出。最后在征得主人同意后，民警和村民合力将这只发疯的狗打死' 
  print '***message***',len(message) 
  for line in fp: 
    line = line[0:-1] 
    word_list.append(line) 
  fp.close() 
  print 'The count of word:',len(word_list) 
  start_time = time.time() 
  for i in range(1000): 
    res = is_contain2(message,word_list) 
    #print res 
  end_time = time.time() 
  print (end_time - start_time)  
 
 
if __name__ == '__main__': 
  dfa() 
  normal() 

----------------dfa-----------
***message*** 224
0.325479984283
------------normal--------------
***message*** 224
The count of word: 100
0.107350111008

----------------dfa-----------
***message*** 224
0.324251890182
------------normal--------------
***message*** 224
The count of word: 1000
1.05939006805