post data 丟失

if you firstly call getParameters to get URL parameter data, then you call getReader to read post data, you may find that post data is missing! so, if you want to get URL parameter data first, then process post data elsewhere, it is recommended to use HttpServletRequest.getQueryString() and parse the parameters yourself, eg, using StringTokenizer.

 

ref: http://www.apl.jhu.edu/~hall/java/Servlet-Tutorial/Servlet-Tutorial-Form-Data.html