需求：

Controller层直接alert

实现：

protected String alert(HttpServletResponse response, String msg, String url) {	response.setCharacterEncoding("UTF-8");	response.setHeader("Content-type", "text/html;charset=UTF-8");	PrintWriter out = null;	try {		out = response.getWriter();		out.print("");		out.flush();	} catch (IOException e) {		e.printStackTrace();	} finally {		IOUtils.closeQuietly(out);	}	return "common/suc";}protected void alertAndclose(HttpServletResponse response, String msg) {	response.setCharacterEncoding("UTF-8");	response.setHeader("Content-type", "text/html;charset=UTF-8");	PrintWriter out = null;	try {		out = response.getWriter();		out.print("");		out.flush();	} catch (IOException e) {		e.printStackTrace();	} finally {		IOUtils.closeQuietly(out);	}}