java中支持前端jq通过ajax提交（post)json内容到控制器

public class TestFilter implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //返回true 则可放行  false不放行
        String type = request.getMethod();

        //添加ajax跨域支持
        if (type.toUpperCase().equals("OPTIONS") == true) {
            response.setCharacterEncoding("utf-8");
            response.setHeader("Access-Control-Allow-Origin", "*");
            response.setHeader("Access-Control-Allow-Headers", "content-type, accept");
            response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
            response.setHeader("Access-Control-Allow-Credentials", "true");
            response.setStatus(200);
            response.setContentType("application/json;charset=utf-8");

            Map<String, Object> resObject = new HashMap<>();
            resObject.put("状态", "成功");
            resObject.put("消息", "接口是通的");
            String data = JsonUtil.toJson(resObject);//这里就是把对象转为json
            OutputStream outputStream = response.getOutputStream();
            byte[] dataByteArr = data.getBytes("UTF-8");
            outputStream.write(dataByteArr);
            return false;
        }
}

　　后端加上这个处理就行了。

前端ajax请求记得设置contentType:"application/json;charset=utf-8"就行了