You have to encode your parameters.
Something like this will do:
import java.net.*;
import java.io.*;
public class EncodeParameter {
public static void main( String [] args ) throws URISyntaxException ,
UnsupportedEncodingException {
String myQuery = "^IXIC";
URI uri = new URI( String.format(
"http://finance.yahoo.com/q/h?s=%s",
URLEncoder.encode( myQuery , "UTF8" ) ) );
System.out.println( uri );
}
}
http://java.sun.com/javase/6/docs/api/java/net/URLEncoder.html