Invalid URI with Chinese characters (Java)

Question

Having trouble setting up a URL connection with Chinese characters in the URL. It works with Latin characters:

String xstr = "维也纳恩斯特哈佩尔球场" ;
URI uri = new URI("http","ajax.googleapis.com","/ajax/services/language/detect","v=1.0&q="+xstr,null);   
URL url = uri.toURL(); 
URLConnection connection = url.openConnection();
InputStream is = connection.getInputStream() ;

The getInputStream() call results in:

java.lang.IllegalArgumentException: Invalid uri 'http://ajax.googleapis.com/ajax/services/language/detect?v=1.0&q=???????????': Invalid query

Answer 1

The problem is caused by the fact that URI.toURL() doesn't percent-encode non-ASCII characters. Use the following instead:

URL url = new URL(uri.toASCIIString());  

Answer 2

axtavt's answer above saved me from insanity, thanks! Just one comment (I could not figure out how to comment below the answer:)

If you start with a URL, you need to encode quotes before you build the URI:

String s = "your_url?with=\"quotes\"";
URI su = new URI (s.replaceAll("\"", "%22");
URL ur = new URL( su.toASCIIString());

Answer 3

I think it is related to the "UTF-8" charset. Have a look at this topic to learn more and also this chinese in java

Answer 4

Per the URI RFC (see section 2.4), non-US-ASCII characters aren't valid in a URI. You must encode them.