ajax后台跨域处理

response.setContentType("text/html;charset=UTF-8");
response.setCharacterEncoding("UTF-8");
response.addHeader("Access-Control-Allow-Origin", "*");	
PrintWriter writer = null;
try {
	writer = response.getWriter();
	String json = JsonUtils.writer().writeValueAsString(rs);//自己封装的bean转json格式的String
	writer.print(json); 
} catch (IOException e) {
	e.printStackTrace();
}finally{
	if(writer!=null){
		writer.close();
	}
}