Phu Nguyen Phu Nguyen - 2 months ago 12
Java Question

URL Encode and Decode Special character in Java

In Java, I need to use HTTP Post to send request to server, but if in the parameter of the URL contains some special character it throws below Exception

URLDecoder: Illegal hex characters in
escape (%) pattern - For input string:

The code to send data

DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(URL);

String sessionId = RequestUtil.getRequest().getSession().getId();
String data = arg.getData().toString();

List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair(param1, data));
params.add(new BasicNameValuePair(param2, sessionId));
httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));

HttpResponse response = (HttpResponse) httpclient.execute(httpPost);

And at the server side, i use the below code to read information

String data = request.getParameter(param1);
if (data != null) {
actionArg = new ChannelArg(URLDecoder.decode(data, "UTF-8"));

The code works correctly but if i input some special character like [aああ#$%&'(<>?/.,あああああ], it will throw exception. I wonder if someone could help me some hint to be able to encode and decode special characters?

Thank you very much in advance.


Sadly url encoder will not solve your problem. I had this problem and used a custom utility. I remember this I got from googling ;).