So my problem is that we are trying to take a chunk of HTML code and, using java, create a PDF file from it for a customer to view. We don't want to make the customer install any third party converters, or use any of the java libraries (like Itext). Is this possible? The easier the solution the better. Maintaining format is a plus but not necessary.
Use a 3rd party library then wrap it up inside your distribution process so that the customer never sees it.
For example use a proper installer to install your program, there are lots of easy-to-use programs to generate installers for you.
Our solution is only client side Javascript and then uses external server to receive that, format it and return it. See http//www.xportability. com/XEPOnline/FOTestSuite.html for early example. The client side will be made available through github soon. The server side is a commercial solution with options for you or us to host. Or you could build your own as it works with XSL FO.
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We have a set of web apps and want to identify if they have a Java client-side dependency i.e. if they invoke the client installed JRE.
Is there an easy way to do this? or do we have to manually scan the code for or anything else that may have a Java client dependency?
Thanks.
No, there is no easy way to do this.
It would be easy if all your web-apps would use a <applet> html tag or a <object> html tag, then you could simply match every html source. This you can do anyway to find some of the web-apps that use java, at least on the start page of the app.
But since it is also possible to load java applets using javascript and an automatism cannot navigate through an app like a user, there is no easy way to do this.
If you have control over the clients (e.g. company internal), you might turn off java on a few clients and let the users do the checking (e.g. they will call if something does not work). Maybe you even have key users for application tests.
Which language/tool do I use to provide an interface between the web browser and a Java application?
My task is create a web page and provide a feature which will enable results to be uploaded as XML files to dynamically update the page.
I have been instructed to use languages such as Java, Javascript(JQuery), Ruby, Grails, PHP etc.
So I have so far written some java classes that will process the XML files but I am running this application from the command line. I DO also understand how to display the XML on the web browser using XSLT.
My problem is, that I have only ever written desktop applications... I don't know what tools to use to provide an interface between my java back-end and the web front-end or how to (for lack of another method) invoke the JVM from the browser.
How do I send uploaded XML files to my java classes and get the XML results back? Can anyone shed some light into which tools I should use and the network packages (if needed) I need to import in Java? (note: this only needs to be run locally)
Feel free to make edits to tags/title and question if necessary.
I have been working in java and i feel that servlet-jsp are the best option
to full fill your requirement.
IDEA: Implement a recent web browser into a java application (for saved offline, non server content).
The question is this: can I have a java application implement a webbrowser with jquery / html / css support within a java program?
So I am asking anyone who has played with JRex for advice: I want to know how complicated will it be to integrate an open source webbrowser into java. I am not all that keen on the idea of compiling Mozilla from source build. Is there a ready made compiled version?
Is there a simplified method to have latest compiled version (most current in terms of support for HTML css & javascript), and integrate that into an application?
Also: I appreciate the amount of work required to support for HTML4 nevermind 5, and CSS2 compliance. How close is JRex to that?
Application: My intention with the webbrowser is to render a webpage from offline content. It will not need to be online content, and will simply be for file based displays = e.g. file:///C:...
Does the webbrowser have to be wrapped into a server to function, e.g. to pass files to the browser to render is how complicated? I am not keen to have to implement Jetty or another server type application just for this.
If JRex is not the solution... what then? Is it possible to start a browser implementation within Java and can Java interact with the information and traverse the Dom?
Or alternatively is there .hta equivalent in recent browsers like firefox?
If you need to have the embedded browser interact with your application code, you could try the SWT Browser control, it's actually maintained as opposed to JRex. Browser uses either WebKit or Gecko or embedded IE as appropriate, or lets you choose which one you want, so it should run jQuery and familiar Javascript. And since SWT is a JNI library to begin with they probably already have guidance on how to deploy an app that uses JNI.
You can feed HTML into the control from a string (example) or a java Url - which can point to local files or resource files in your JAR, which I assume will let you split your app into different files.
To call Java code, you need to expose it as Javascript functions. example
To manipulate the HTML from Java code, you need to call Javascript functions from Java. example
To make the previous two tasks easier, you might want to look into a JSON library to simplify passing around complex data.
Does it have to be implemented within a Java program? Could you let the user use the default browser on their machine (ie does it matter what browser)?
If not would use the Java Desktop API.
if (desktop.isSupported(Desktop.Action.BROWSE)) {
txtBrowserURI.setEnabled(true);
btnLaunchBrowser.setEnabled(true);
}
If you are using Java 1.5 try http://javadesktop.org/articles/jdic/
I am newbie in wkhtmltopdf. I am wondering how to use wkhtmltopdf with my Dynamic Web Project in Eclipse? How to integrate wkhtmltopdf with my Java dynamic web application?
Is there any tutorials available for beginners of wkhtmltopdf ?
(Basically, I would like to use wkhtmltopdf in my web application so that when user click a save button , the current page will be saved to PDF file).
First, a technical note: Because you want to use wkhtmltopdf in a web project, if and when you deploy to a Linux server machine that you access via ssh (i.e. over the network), you will need to either use the patched Qt version, or run an X server, e.g. the dummy X server xvfb. (I don't know what happens if you deploy to a server running an operating system other than Linux.)
Second, it should be really quite simple to use wkhtmltopdf from any language in a web project.
If you just want to save the server-generated version of the current page, i.e. without any changes which might have been made like the user filling on forms, or Javascript adding new DOM elements, you just need to have an extra optional argument like ?generate=pdf on the end of your URL, which will cause that page to be generated as a PDF, and then the PDF button will link to that URL. This may be a lot of work to add to each page manually if you are just using simple JSP or something, but depending on which web framework you are using, the web framework may offer some help to implement the same action on every page, if you need to implement that.
To implement this approach, you would probably want to capture the response by wrapping the response object and overridding its getWriter() and getOutputStream() methods.
Another approach is to have a button "submit and generate PDF" which will generate the next page as a PDF. This might make more sense if you have a form the user needs to fill in - I don't know. It's a design decision really.
A third approach is to use Javascript to upload the current state of the page back to the server, and process that using wkhtmltopdf. This will work on any page. (This can even be used on any site, not just yours, if you make it a bookmarklet. Just an idea that occurred to me - it may not be a good idea.)
A fourth approach is, because wkhtmltopdf can fetch URLs, to pass the URL of your page instead of the contents of the page (which will only work if the request was a HTTP GET, or if it's equivalent to a HTTP GET on the same URL). This has some small amount of overhead over capturing your own response output, but it will probably be negligible. You will also very likely need to copy the cookie(s) into a cookie jar with this approach, since presumably your user might be logged in or have an implicit session.
So as you can see there are quite a lot of choices!
Now, the question remains: when your server has the necessary HTML, from any of the above approaches, how to feed it into wkhtmltopdf? This is pretty simple. You will need to spawn an external process using either Runtime.getRuntime().exec(), or the newer API called ProcessBuilder - see http://www.java-tips.org/java-se-tips/java.util/from-runtime.exec-to-processbuilder.html for a comparison. If you are smart about it you should be able to do this without needing to create any temporary files.
One of the wkhtmltopdf websites is currently down, but the main README is available here, which explains the command line arguments.
This is merely an outline answer which gives some pointers. If you need more details, let us know what specifically you need to know.
Additional info:
If you do end up trying to call wkhtmltopdf in an external process from java (or for that matter, any language), please note that the "normal" output that you see when using wkhtmltopdf from the command line (i.e. what you would expect to see in STDOUT) is not not in STDOUT but in STDERR. I raised this issue in the project page
http://code.google.com/p/wkhtmltopdf/issues/detail?id=825
and was replied that this is by design because wkhtmltopdf supports giving the actual pdf output in STDOUT. Please see the link for more details and java code.
java-wkhtmltopdf-wrapper provides an easy API for using wkhtmltopdf in Java.
It also works out-of-the-box on a headless server with xvfb.
E.g., on a Ubuntu or Debian server:
aptitude install wkhtmltopdf xvfb
Then in Java:
Pdf pdf = new Pdf();
pdf.addPage("http://www.google.com", PageType.url);
pdf.saveAs("output.pdf");
See the examples on their Github page for more options.
I want to know how to convert html file to image. How do I do this?
You can checkout the source code for the popular BrowserShots service,
http://browsershots.org/
If you're running Windows, and have the GD library installed, you can use imagegrabwindow. I've never used it myself, but as always, the PHP site has lots of documentation and examples.
Use:
WKHTMLTOPDF.
It also has binding to PHP, or you can run it yourself from command line.
Problem is that you need to implement all the functionality of a browser and an HTTP stack (and this still does not deal with the case where the content is modified using javascript).
As John McCollum says, if you've got the website open in a browser on your PC, then you can use imagegrabwindow or snapsIE (MSIE only)
If you want to to be able to get a snapshot using code only, then you might want to look at one of the off the shelf solutions - AFAIK there are several programs (at least 2 of which are called html2pdf) which will generate a PDF of static html - and its relatively easy using standard tools to trim this to window size and convert to an image file.
e.g. https://metacpan.org/pod/distribution/PDF-FromHTML/script/html2pdf.pl