Today I'm using an applet to modify client-side information, considering the new browsers i have to found out a new workaround to continue modifying file and execute windows command at client-side because some browser are suspending the applet execution.
Any ideia for solution that has allow windows command execution and access file at client side like Activex ?
Applets have always been sitting between webapps and desktop apps. In that sense, what you want to achieve is exactly what every hacker in the world wants to achieve, that is gain access to your computer from a browser. And I think it would fair to say that for that reason, applets are dying and are not coming back from the dead anytime soon.
But unfortunatly some functionalities need applets to run, and what you can do really depends on those functionalities.
Statu-quo
They are still working in IE (not Edge), Firefox and Safari. If you control your clients environment you can maybe still use them as is. But for how long ?
Move to Server
You move your functionalities on the server. In your case, it would probably mean upload files on the server, execute your commands there and send the file back on the client. Javascript and HTML 5 can certainly help here improve the overall user experience.
Move to Desktop
If you are doing some pretty intensive stuff on the client (processing multiple files, accessing resources that cannot be used from a browser, etc), you should consider regrouping this into a desktop app. You can even launch your app from a browser and sends some parameters to it by registering a Custom Protocol Handler, a la iTunes. Again, this is certainly not an easy replacement, as functionalities will often be spread out between the desktop app and the web app, which makes for some interesting scratch head moments trying to link the 2.
Related
So, how much trust do I need to have in a publisher before I run their applet in the web browser?
In other words, I understand that a java applet is run in a sandbox in the browser, but this article suggests that the applet can actually access files stored on the local computer.
Can you please clarify the security limits of a java applet run in a modern browser, such as Firefox 50?
I understand that a java applet is run in a sandbox in the browser, but this article suggests that the applet can actually access files stored on the local computer.
There are potentially three different levels of security available to a Java applet.
The first is as you described 'sandboxed'. They can only access resources from their own server, nothing on your local file system unless they are launched using Java Web Start & will thereby have access to the services of the JNLP API. You might note that two of the services are the FileOpenService / FileSaveService! If the applet goes to use these, the end user will be prompted to permit the action via a dialog that states what the applet is trying to do, and asking for permission to proceed (to show a file chooser & go from there). These services provide back a 'file like' object that is more limited than the normal File API would supply. For example, it will not provide the path to the resource, just it's name and access to the content.
The level up from that can be specified in the launch file - '(J2EE) application client permissions'. This level removes the prompts for use of the JNLP API services.
The highest level of access is obtained by requesting, and being granted, 'all permissions'. Then the applet should have full access to File objects, be able to communicate with servers other than the one that launched it, etc. One of the few things they would still not be permitted to do in this mode is to call System.exit(n) to effectively 'kill the JRE' - this is something that is commonly done in other desktop apps.
But then there are JRE bugs, that screw all that up. Sun, then Oracle, kept stuffing up security so poorly (& regularly) that many browser manufacturers are entirely removing the support for applets (and other embedded objects requiring plug-ins) in web pages.
See Java Plugin support deprecated and Moving to a Plugin-Free Web for more detail.
..how much trust do I need to have in a publisher before I run their applet in the web browser?
I cannot answer for you, but my take would be that I would need to know them personally, and trust completely both their integrity and competence before I'd run their code in any browser I controlled.
Having said that, I don't think I have a single browser installed that even supports applets, and my complete lack of motivation to set something up, is probably a good view on whether I'd allow applets to run on this PC at all.
I want some way of creating a dedicated browser window for a browser (chrom-e/ium or firefox). Its content needs to be controlled by a java application (a http call to localhost or better a more direct way of communicating). These two should be bundled together in some way.
A little Background
I want to write a java desktop app but don't want to use Swing or javaFX for the UI. The UI should be written like a one page app and may be ported (at least partially) to the web. I have taken a look at the javafx WebView but would rather have a full fledged browser on my hands. It would also be nice to have a little more control over said browser to send files and read files in a more desktopish way. The only real requirement is that there has to be some java backend behind it and that is has to work offline.
Is something like this possible at all or is it just a pipe dream?
I am very almost a year late for the party, but:
There are a few (that I know) technologies that can help you:
Electron. It is basically what you want, you can use web
technologies to "forge" a desktop app, it's quite well known, I never used it but for what I have read that you can stick almost anything to it's "backend".
JavaFxWebView. There are some really nice ways to use it, you can
even use bootstrap and AngularJs, here is a example (not by me)
Yes it's possible and not all that unusual. Your app can open a default browser as described here -
https://stackoverflow.com/a/10967469/5087125
And then proceed to respond to http requests to your app.
I am developing a web application using HTML5, AngularJS, REST Webservices, Java etc. I will be hosting it over company's intranet. I have a peculiar requirement where I need to run exes which are already copied to client machine. The 'run' should be triggered from backend java code and user need not click on any UI link.
I am exploring Java Web Start, but I guess some user interaction in mandatory in it. If some signed content, certificates are required I can do that.
Is this feasible?
What you want is exactly what any virus builder dreams of. Therefor, it has been made VERY difficult. There are only 2 ways in which I think you could do this:
Use a java applet. It needs to be signed perfectly and the security settings in the users browsers need to be lowered. Even then I'm not entirely sure they don't have to click 'accept' somewhere.
Create a browser plugin. You could write a browser plugin, which would allow you to do basically anything you want. You would need to install it everywhere though.
If there is any way of getting around the requirement of running an exe from a web browser, I suggest you take it.
I've been trying to understand how flash animations or a Java Applet work within a browser.
I can think of a couple of ways -
The Flash Player/Java Applet are machine code that's dynamically linked it, and given
some parameters about the area of the screen that belongs to them; after that, they
run within the same process space.
The browser exposes an API that the player/applet use to talk to it and they live
in a separate process. (Presumably they talk via sockets?) The API could correspond to
openGL/X11/some custom calls.
These possibilities still don't explain things like how a button click can make the
player full-screen, how it can play music, how it can inspect the DOM, etc. For that matter,
is the video displayed by decoding to a sequence of images, and rendering them
one at a time, or is there a more efficient way, e.g., of pushing the deltas in the image?
The Wikipedia page on Java Applets (1)
talks about how the applet is run in a sandbox (presumably a separate process), but
it doesn't say how the browser and the applet communicate.
Perhaps the answer depends on the underlying platform?
Any pointers to systematic discussion of this topic would be appreciated (as would
a reference to the APIs).
(My interest in this stems from an insatiable curiosity.)
I'm pretty sure plugins like Java applets and Flash run via NPAPI in most browsers. I looked into this matter myself some time ago and NPAPI was the answer I found.
In the case of browser and Java applets, the applets are typically run within the Java plugin, which runs as a separate process (you can see it e.g. in the task administrator in Windows).
The plugin creates an object for each applet in the DOM, and you can thus interact with the applet from Javascript. Anyway, calls to the applet that take a while to return do have the effect to freeze the browser, therefore I'd say the communication with the plugin runs in the same thread as the main refresh loop. This seems at least to be the case with Firefox.
I am working on an application in Linux which will interfaces with hardware. One of the requirements is to create the GUI in Web-browser . the application will be c++ based. I m not familiar with web realted stuff so i want to know Is it possible to do such a thing (currently it's a console application take input from txt file/cmd line). gui will be simple using button and showing output messages on browser from the application. i want to know which technologies/languages are involved and how can it be done. some of the idea i read but havn't found anything concrete yet. if u have any idea about these or a better suggestion please share
run the app in background and communicate with browser ?
call library functions directly from browser ?
any other idea ?
I would start by setting up a regular HTTP server, like lighttp or Apache httpd.
You say you already have a command line program that does the actual work - As a first step, I would reuse that, and configure the web server to call your program using CGI - see forexample http://httpd.apache.org/docs/2.2/howto/cgi.html for apache
Finally, I'd pick some javascript framework like jQuery or YUI with Ajax capabilities to do requests to the server to call the CGI script from within a webpage. You could also create a form-based web application without ajax or any framework, but that would require you to stuff all kinds of logic in your program to generate HTML pages. By using Ajax, you can leave the command line application as is, and parse any responses it gives with javascript, and then use that to dynamically change the webpage in a way that would make sense to the user.
If this all works, then I would try to figure out how to package all these components. Perhaps you just want to create a simple archive with all the programs inside, or maybe you want to go as far as actually embedding the webserver in your program. Alternatively, you may want to do it the other way around and rewrite your program as an ISAPI module that you can plug into your webserver. Or if that's not integrated enough still you could write your own (partial) HTTP server. That's really up to you (I'd probably spend time and energy on searching for the leanest, meanest existing open source http serverr and use that instead)
At any rate, the prior steps won't be lost work. Most likely, developing the web page is going form a substantial part of the work, so I would probably create a quick and dirty working solution first using the age-old CGI trick, and then develop the webpage to my satisfaction. At that point you can already have an acceptable distributable solution by simply putting all programs in a single archive (of course you would have to tweak the webserver's configuration too, like changing the default port so it won't interfere with existing webservers.) Only after that I would spend time on creating a more integrated fancy solution.
I ended up using Wt though I'd update for future reference.
These are how I thought of doing this, in order of complexity for me:
Create a simple server-side-language (PHP/Python) website that can communicate with (ie launch and process the return of) your application
Modify your application to have a built-in webserver that just punched out HTML (command line parameters taken through the URL)
Modify the app to publish JSON and use javascript on a simple HTML page to pull it in.
You could write a Java applet (as you've tagged this thread) but I think you'd be wasting time. This can be quite simple if you're willing to spend 10 minutes looking up a few simple commands.
After 12 years, web browser-based GUI started to appear, WebUI is one of them.