問題描述;工作上遇到要在一個RequestMapping 方法裏適配返回值爲string 或者json對象;
以下是解決方案(部分涉及業務邏輯請忽略);
1,RequestMapping方法:
@RequestMapping(method = RequestMethod.GET, value="/product/read")
public ModelAndView productRead1(Model model,HttpServletRequest request,HttpServletResponse response,@RequestParam("id") Long id,@RequestParam(value="returnType",required=false) String returnType){
JSONObject rs=CommonUtil.commEnterSend("/portal/product/productQRcode/"+id,SSOClientUtil.GET,null);
model.addAttribute("proBarcode",rs.get("proBarcode"));
if(returnType==null){
JSONObject product=CacheUtil.getProductByCode(rs.get("proBarcode").toString());
model.addAttribute("FDA","GY");
model.addAttribute("product",product.getJSONObject("data"));
ModelAndView mv =new ModelAndView("FDA/read","keyword",rs.get("proBarcode"));
return mv;
}
else{
return JsonViewUtil.Render(model, response);
}
}
2.寫一個適配類:
import java.io.IOException;
import javax.servlet.http.HttpServletResponse;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageNotWritableException;
import org.springframework.http.converter.json.MappingJacksonHttpMessageConverter;
import org.springframework.http.server.ServletServerHttpResponse;
import org.springframework.web.servlet.ModelAndView;
public class JsonViewUtil {
public static ModelAndView Render(Object model, HttpServletResponse response)
{
MappingJacksonHttpMessageConverter jsonConverter = new MappingJacksonHttpMessageConverter();
MediaType jsonMimeType = MediaType.APPLICATION_JSON;
try {
jsonConverter.write(model, jsonMimeType, new ServletServerHttpResponse(response));
} catch (HttpMessageNotWritableException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
3.通過這個適配類JsonViewUtil.Render方法將json封裝在response一併返回
4。遇到的問題:(a):返回值爲ModelAndView 的方法不能直接return json;(b):一開始我通過HttpServletRequest的getCookies()方法獲取請求帶有的cookie,用來判斷請求來自web端還是移動端,後來需要將微信掃碼和QQ掃碼加入,於是在移動請求加入了一個字段,這裏一個所得是:可以通過HttpServletRequest的user-agent參數判斷請求來自移動端還是web 以及使用的移動端型號和我web端瀏覽器類型