java服务器端接收json格式传递的参数

1，传递参数的两种访书，第一是key-value形式,对于这种我们在服务器端直接使用 request.getParameter("key");就能获取key对应的value。下面是代码：

@Controller
@RequestMapping("/api/log/logprint")
public class HelloController {
	@RequestMapping(method = RequestMethod.POST)
	public String printWelcome(HttpServletRequest request, HttpServletResponse response,ModelMap model) {
		model.addAttribute("message", "Hello world!");

		////接收参数
		String logBody = request.getParameter("log_body");
		System.out.println("====logBody="+logBody);

		return "hello";
	}
}

 

2，第二是json格式，但是对于传递的json就不能使用这样的代码了，

利用json传递的参数存在request的body里，我们需要从里面输入流里面读取，下面是代码：

public class LogPrintInterceptor extends HandlerInterceptorAdapter {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        ////接收参数 获取logBody、requestId
        String requestId = request.getHeader("requestid");
        String input = null;
        StringBuffer requestBody = new StringBuffer();
        try {
            BufferedReader reader = request.getReader();
            while((input = reader.readLine()) != null) {
                requestBody.append(input);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        if (StringUtils.isNotBlank(requestId)) {
            return true;
        }else{
            return false;
        }
    }
}

 3，第三是也是json格式，和第二种不同的是直接转为java对象，下面是代码：

请的JSON数据：

{
    "uname":"81110318",
    "pwd":"d59cd7385c99fe94c70be3396d7d004c"
}

 接收的Java代码：

@Controller
@RequestMapping("/api/login")
public class UserController {

	@RequestMapping(method = RequestMethod.POST)
	public String login(@RequestBody User user,HttpServletRequest request, HttpServletResponse response,ModelMap model) {
		model.addAttribute("message", "Hello world!");
		System.out.println("uname="+user.getUname()+", pwd="+user.getPwd());

		return "hello";
	}
}