Hello, everybody!
Please, look at this picture! You see IE and HttpWatch Basic plugin loading yahoo.com. You see a range of any http responses. But the most important is the list of loaded images. Some of them are loaded during JavaScript scripts executing, some of them are loaded during AJAX works. The URI's of this images are not accessible from HTML code.

Unfortunately java.net package don't let us to get all this headers and URI's of images using standard tools. If You try it

import java.net.*;
import java.io.*;

public class Main {

    public static void main(String[] args) throws MalformedURLException, IOException {      
    try {
   URL url = new URL("http://www.yahoo.com");
   URLConnection conn = url.openConnection();
   for (int i=0; ; i++) {
   String headerName = conn.getHeaderFieldKey(i);
   String headerValue = conn.getHeaderField(i);


   if (headerName == null && headerValue == null) { break; }
    } catch (Exception e) { }

You'll see it! And now the question: does anyone knows any tools or library or ways for getting all headers like HttpWatch Basic plugin ? Thanks!

You must learn to understand what you're actually seeing as you are utterly WRONG about what is happening.

Those pictures and other things are each loaded as a separate http request, so it's not strange at all they're not showing up in your listing of headers.
In fact you are misinterpreting multiple http responses as being multiple headers in a single http response.