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Jsoup Issue scraping non-hardcoded data

I'm trying to use Jsoup to gather wave height information from Surfline.com. I have the element I desire in the screenshot and the it's showing in the dev tools. When I scrape the site with Jsoup, the returned string includes everything seen in the dev tool but the "1-2ft" which is what I need. The site is Javascript heavy and I'm assuming that jsoup is snagging the html before the javascript actually runs (I have no clue really). Do I need to specifically tell jsoup to wait for the pageload or am I missing some other critical component?
This is the code I'm using.
Document doc = Jsoup.connect("http://www.surfline.com/surf-report/folly-beach-pier-southside-southeast_5294/").get();
Elements content = doc.select("div[id=current-surf-range]");
System.out.println(content);
and this is the output I'm seeing in my IDE
<div id="current-surf-range" style="font-size:21px;font-weight:bold;padding-top:7px; padding-bottom: 7px;"></div>
it seems really odd that the contents of the div wouldn't be returned with it. This is my first time using Jsoup and I tried to read through the docs as best I could but nothing seemed to touch on this particular issue. Any insight would be awesome and greatly appreciated.

What you see in the browser is not what necessarily you would get when download the page by URL with your HTTP library of a choice. In fact, you should never expect them to be the same. In the modern web, webpages are quite dynamic and are loaded asynchronously involving multiple API calls to different resource providers and javascript being executed in the browser (which has the javascript engine).
What you get with JSoup in this case is the initial HTML that browser starts to form the page with. Then, there is a set of XHR calls to the surfline API that brings the data into the browser which then dynamically fills up different parts of the page, including the current surf range.
The simplest way to approach the problem is to switch to browser automation tool called selenium which would fire up a real browser. You can then wait for the current surf range element to have a value and, if you wish to continue with JSoup, get the page source and feed it to JSoup for further parsing.
Another approach would involve looking into the requests that the page makes in the browser developer tools and then try to simulate these requests in your code, parsing the JSON responses and extracting the surf forecast data.

Getting web page source code in Java

I use Java. I want to get web page source code but on the page works JavaScript and I want get code generated by JavaScript (code which we see in firebug in firefox)
Anyone knows what I should do?

To inspect the page after modification by JavaScript, you need a client-side JavaScript engine that can run the scripts and then let you inspect the DOM.
HtmlUnit can do this - it is a "GUI-Less browser for Java programs".
See also this question
However, this won't give you the exact original page source, because that has already been parsed into a DOM by this point.

I think you want to see the source code of DOM Elements created after the page load via AJAX.
If that´s what you want, the only way to see it is through a DOM inspector, like firebug in firefox or Developers Tools in Chrome.
Going to "View source code" only shows the source at load-time.

If I understand your question, yes your javascript objects can be passed back to your java backend either by a creating a html <form> element with inputelements, fill them with your values and then submit the form, or asynchronously via ajax/json (which doesn't require re-loading your web page). For both methods you need to configure an endpoint on your java side to receive the submitted data and return some kind of confirmation to the client, i.e. your javascript. I would recommend googling "jQuery.post" for the javascript side and finding some examples for your java backend.

Convert Web Page to PDF or Image

I need to convert a web page [which has not public access] to PDF or Image [preferably to PNG].
Web page contains set of charts and image. Most of the charts are populated through Ajax calls so there is a delay between page load and chart load.
I am looking answer for any of these questions:
1- I found set of snapshot api's but none of them support accessing my internal page. Since the web page I am trying to export is not public I need to be authenticated. Biggest problem is I cannot send request headers [such as session-id, cookie or other variables] along with these API's. It seems they don't support this kind of functionality.
2- I am not sure if I can do following: Login to my web page with HTTP client, add http headers, send get call and get HTML string. Then use one of the converters to convert it to PDF. What I am not sure is if it's possible to get proper PDF from the HTML string I got from http client since resources [css, js and etc] will be missing. I want my pdf/image looks exactly as it on the web site.
I really appreciate if you can help.
Thanks in advance,
ED

You're probably best of using wkhtmltopdf, which is a server-side tool and is easily installed.
There are two parameters you can use to wait for your Ajax to finish, try:
javascript-delay to influence the time the program waits for the JavaScript to finish
window-status to wait for a certain return code for the window
See the extensive manual for this program here
wkhtmltopdf generates a PDF and wkhtmltoimg generates an image, which is PNG (as you requested) by default.

Authentication is difficult because it involves security. Because the operation you are describing is unusual it is likely to result in all kinds of alarm bells going off. It is entirely possible to do but it is fraught, easy to get wrong and fragile in the face of security updates and code changes.
As such I'm going to suggest an alternate method which is one we often recommend for ABCpdf (on which I work). Yes we support standard authentication methods but the beauty of this approach is that it is robust and is applicable to other solutions (eg Java based) and novel authentication methods.
Typically you just want a PDF of the current page. The easiest way to do this is snaffle the HTML. The way you do this rather depends on your environment. For example under ASP.NET you can obtain the HTML of the current page using the HttpResponse.Filter property or by overriding the Render method of the page. The way you do it will depend on what you're coding in.
Then you need to save this HTML to a file and present it to your solution via a 'file://' protocol URL. Now obviously at this point any relative links will be broken but this is easily fixed by dropping in a BASE tag that references the place they are located.
Generally the types of resources referenced by an server-side page are static. So if you can create a tag that references the actual files rather than a web site, you will bypass any authentication for access to these resources.
That still leaves the AJAX based problems which are another can of worms. The render delay method is something we have supported for many years (from before AJAX was around) however it is not terribly reliable because you just don't know how long to wait.
Much better is a tighter link into the JavaScript via a callback you can use to determine if the page is loaded. I don't think ABCpdf is going to be appropriate for you since it is .NET but I would certainly encourage you to look for a Java based solution that uses this type of more sophisticated approach.

Accessing the same file

I have a situation where in I write to a text file programmatically using java and simultaneously I read from the same file using jQuery.
The problem I face is jQuery is unable to find the updated content whenever a content is written into the text file via java.
I have Googled a lot but the only results I find are for java and java processing and not for java and javascript (i.e A Client side and Server side)
I am not sure if this is even possible.
More about the question:
I write into the file the crawling results using java and I am trying to display the same using javascript (jQuery.post() method).
JAVA
A multi-threaded crawling program that crawls a website and does some functionality. I am trying to write some content into a text file using the same java program as and when the crawling happens. The content I write mostly are the details about which thread is getting invoked and what is the current link that is being crawled.
The reason I write this in the text file is I need to show the output in the UI so that people looking at the UI will understand what happens.
Writing happens perfectly as expected.
JAVASCRIPT (jQUERY)
This using the
jQuery.get or post ("sample.txt", function (result) {
$("#someID").html(result);
});
It reads from the text file normally but when java and javascript both are trying to access the file, It is the java that dominates leaving javascript behind thus jQuery is unable to fetch the updated content as and when it happens.
I guess this explanation is more than sufficient to make people understand what exactly my problem is !
On the whole, java and javascript try to access the same file at the same time. So there comes this issue.
Any help is appreciated.
Thanks in advance

I think the file is cached. Easiest thing is to request the file by different urls. Try something like "sample.txt?rnd="+Math.rand()

There can be synchronization problems and your data will be corrupted.

I have a question, is it must be done with Ajax? I think you are trying to figure out about
Ajax push and pull
This is not very easy to do and I wouldn't really recommend it. However, there is a better technology called websocket. So what you can do is, client can submit request to the server to write data into a file then server can send back updated content to the client. Moreover, this is much better than achieving the same objective through numerous amount of HTTP requests.
Additionally, if you want the crossbrowser compatibility, have a look at http://socket.io/

Thanks for all those who were trying to help me out.
I have finally come up with a solution. I, instead of using jquery post to directly read from file, am using another jsp file that reads the file contents and prints using out.println on screen, and after which I am using jQuery post to get the content written by that jsp file. Hence the synchronization problem is avoided.
Here is more about my explanation:
Earlier I had
java program -> Text File <- javascript (jQuery post) // Resulted in synchronization problem where in javascript was not able to access the updated content.
Now
java program -> Text file <- JSP file <- javascript (jQuery post) // Avoided the synchronization problem as that file is accessed by the same server side language. After that jQuery reads the content printed by JSP page.
After many changes, finally came up with one good working solution.
Thanks all.

Display external webpage into a webpage in my application

i want to display an external webpage (exactly as it's rendered in that site) into a webpage in my application in a way that's fast and better for SEO crawlers, and i was wondering if there's a way to do that with javaee ?
if not then what is better in performance and for SEO the XMLHTTPRequest way or the iframes way.
please advise with sample code or link if possible, thanks
Update: example website is: http://www.akhbarak.net/

If you need to display content from different pages inline, use iframe (iframe stands for inline frame - it has nothing to do with Apple).
If you'd like to use AJAX to display pages, I would recommend colorbox.
Note that accessing pages in a different domain via AJAX is next to impossible - this is a very, very big security hole. I would not recommend doing it. You would have to use a proxy on your own server to fetch the page and return its HTML.
That said, using the iframe in your source code, so it is loaded with the rest of the page, seems like your best bet. Sites like facebook and twitter use this in embeddable "like" and "tweet" widgets so that those widgets can make requests on their own domain - that is, twitter or facebook. While managing lots of iframes isn't very fun, it is a very accepted way of doing what you want to do.

In theory, you could
load the whole page into a PHP variable,
replace the body tags with ,
take out the html tags,
pull out the entire section and put it in the encompassing pages ,
and replace all links with absolute ones (ie '/images' changes to 'http://example.com/images')
Would it be easy to do? Probably not. It's the only way I can think of to accomplish it so that the site appears as part of yours though.