public boolean userTest(User u) {
		// ѯݿSQL
		String sql = "select * from user where name=\'" + u.getName()
				+ " \'and pass =\'" + u.getPass() + "\'";
		
		conn = manager.getConnection();
		try {
			stmt = conn.createStatement();
			rs = stmt.executeQuery(sql);
			// жûǷݿ
			if (rs.next()) {
				return true;	// ڣ
			} else {
				return false;	// ڣؼ
			}

		} catch (SQLException e) {
			e.printStackTrace();

		} catch (Exception e) {
			e.printStackTrace();
		}

		finally {
			// رݿ
			manager.closeAll(rs,stmt,conn);
		}
		return false;
	}