Bug 98104 Javadoc locations in archives should correctly handle ! in path
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavadocConfigurationBlock.java
private boolean checkURLConnection(URL url) {
		int res= 0;
		URLConnection connection= null;
		try {
			connection= url.openConnection();
			if (connection instanceof HttpURLConnection) {
				connection.connect();
				res= ((HttpURLConnection) connection).getResponseCode();
			}
			InputStream is= null;
			try {
				is= connection.getInputStream();
				byte[] buffer= new byte[256];
				while (is.read(buffer) != -1) {
				}
			} finally {
				if (is != null)
					is.close();
			}
		} catch (IllegalArgumentException e) {
			return false; 
		} catch (IOException e) {
			return false;
		}
		return res < 400; 
	}
 	
	
	private class JDocConfigurationAdapter implements IDialogFieldListener {