def insertDomain(self, domain, indegree=0, outdegree=0):
		'''增加一个域名'''
		cur = self.conn.cursor()
		cur.execute("INSERT INTO Domains VALUES (NULL,?,?,?)", (domain, indegree, outdegree))
		# 写入到文件中
		self.conn.commit()
def drawMe(self, g):
        self.g = g
        self.g.beginPath()
        self.g.moveTo(self.p1.x,self.p1.y)
        self.g.lineTo(self.p2.x,self.p2.y)
        self.g.stroke()