jersey POST 方法报错（MediaType出错），大家用过的知道是什么原因吗？该怎么处理

    @POST      @Path("test_post4")    @Consumes("application/x-www-form-urlencoded")     @Produces("text/plain")      public String getTest22222(InputStream is, @Context HttpServletRequest request) throws Exception{          byte[] buf = new byte[is.available()];          is.read(buf);          System.out.println("buf:"+new String(buf));          String result;           result= "--------"+request.getContextPath();                return result;      }  

    public static void main(String[] args) throws URISyntaxException {        // TODO Auto-generated method stub            URI u = new URI("http://localhost:8088/getstart/test_post4");        System.out.println(u);        Client client=Client.create();;        WebResource resource = client.resource(u);             String buf = "inputstream content.";          ByteArrayInputStream bais = new ByteArrayInputStream(buf.getBytes());          String result = resource.entity(bais).post(String.class);          System.out.println(result);      }