Problem with parser

Question

I have never been interested in parsing sites before, but now I need to parse the VK page. I wrote such a code, which, as I understand it, should output Online. But he takes nothing at all. What is the problem? No errors

public static void main(String[] args) throws IOException { Document doc = Jsoup.connect("https://vk.com/id94283688").get(); List<String> strings = new ArrayList<>(); Elements h4Elements = doc.getElementsByAttributeValue("class", "profile_online"); h4Elements.forEach(h4Element -> { Element element = h4Element.child(0); strings.add(element.text()); }); for (String s :strings) { System.out.println(s); } }

Here is this element:

 <h4 class="profile_online"><div id="profile_online_lv">Online<b class="mob_onl profile_mob_onl unshown" id="profile_mobile_online" onmouseover="mobileOnlineTip(this, {mid: cur.oid, right: 1})" onclick="mobilePromo(); "></b></div> </h4>

PS: I am new and do not have much knowledge in programming

Obviously, if the code prints nothing, then h4Elements contains no elements.
In general, it is more correct to use the VK API, and not to download the page.

Accepted Answer · 2016-08-18T15:14:00

The problem is that you have an empty h4Elements .

To get what you need, you can use, for example, the div#profile_online_lv .

Upd. See what you have in doc . Then install the correct User Agent and look again at what is in the doc .

Upd 1. You can use the method:

 static boolean isOnline(String url) throws IOException { Document doc = Jsoup.connect(url).get(); if(doc.text().indexOf("Online") != -1) return true; return false; }

But note that there are pages whose contents are not available without authorization . For such pages you will receive false . Although in reality this may not be the case.

This is for you as an example, not very good, but still.

I tried this: Element element2 = doc.getElementsByAttributeValue ("id", "profile_online_lv"). Get (0);
@Nick, Well, do not I give you a quote on the first link from the search results?
Read what the user agent is, and then look towards the Jsoup.userAgent(...) method.
Document doc = Jsoup.connect (" vk.com/zhenya_silver").userAgent("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit / 537.36 (KHTML, like Gecko) Chrome / 47.0.2526.80 Safari / 537.36") .get ();

Nick nick 22 four · Answer 2 · 2016-08-18T15:27:22

I needed to check if the person was online. Changed the code for this:

 Document doc = Jsoup.connect("https://vk.com/id94283688").get(); Element element2 = doc.getAllElements().get(0); if (element2.text().contains("Online")) { System.out.println("Online"); } else { System.out.println("No"); }

It seems everything works!

He writes No on some, but I doubt that it works correctly ... How to make more accurate?

Problem with parser

2 answers 2

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