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 __init__(self, x, y, w, h):
		self.x = x
		self.y = y
		self.w = w
		self.h = h
		self.center = (self.x+int(self.w/2),self.y+int(self.h/2))
		self.distance_from_center = sqrt((self.center[0]-MAP_WIDTH/2)**2 + (self.center[1]-MAP_HEIGHT/2)**2)