def insertRuleset(self, ruleset, domain):
		'''增加一个robots.txt规则集'''
		cur = self.conn.cursor()
		cur.execute("SELECT did FROM Domains WHERE domain=?", (domain,))
		did = cur.fetchone()[0]
		cur.execute("INSERT INTO Rulesets VALUES (NULL,?,?)",(did, ruleset))
		# 写入到文件
		self.conn.commit()
def setPP(self, p1, p2):
        self.p1 = p1
        self.p2 = p2
        self.Tail = self.p1
        self.Head = self.p2
        self.length = math.sqrt(math.pow(self.p2.x-self.p1.x, 2)+math.pow(self.p2.y-self.p1.y,2))