I have a "proof of concept" piece of work that crosses over into some unfamiliar territory. I have some experience on J2EE technologies. I'm tasked with connecting an EFTPOS machine to an web application. I am planning to use applet to interact with dll. dll will be running on the client side.
I need to interact with one dll from web application. Please provide me any guidance on this, as I am new to it. I tried interacting with dll from standalone java program, but not able to connect from web application. Any sample codes will be very helpful for me.
Yes that is perfectly possible with an applet. I "connected" an electronice signing device before and it was working very well. Depening on what kind of .dll we are talking about here you need to do the following things:
1.) Create a java access layer / interface for your dll, so that you are able to call the dll functions from java. Depending what kind of dll we are talking about there are several possibilities. The base technology is JNI which is however quite cumbersome to use but luckily there are much more convienient ways out there:
use JNA (if it is a C dll)
use Jacob (if it is a COM component)
use bridj (if it is a c++ dll. You may try swig but haven't used that, so can't tell)
2.) Put your dll inside a jar file and distribute it alongside your applet. How this works is quite nicely described in the jacob project which provides an example for that. You can find it in the source package under jacob-1.17_src.zip\jacob-1.17\samples\com\jacob\samples\applet The example describes the JNLP way to access a native library which will work above java version 1.6.0_10. If you have to use a lower version for some reason, it is also possible but is slightly more tricky...
3.) One more side note: Since the latest available java version (1.7.0_51 or 1.6.0_71) due to security, some rules have been added or tightened for java applets. Now you have to sign your applet with an official certificate and set the right attributes/properties in the manifest, jnlp files. But this has been discussed in great detail here so just search for it. I would probably use a slightly older version for development and if that is working, figuring out how to make it work in the latest java version...
4.) Regarding the interaction part there are also several possibilities. Your Java Applet can call jscript methods from the website it is running in (or also the other way around) or the applet directly communicates with your server. You have all possibilities on that front...
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I have a 3rd party legacy app that requires a VB6 Active X EXE library interface. I am looking to update the VB6 Active X EXE library to a currently supported language. As the legacy host application is from a 3rd party I do not have the ability to change the host API to use an interface other than ActiveX EXE. Is there any currently supported Microsoft language i.e., x86 C++, C++/CLI, C# or VB.NET that can create the equivalent of an ActiveX EXE interface?
I suspect the answer is no but am looking for a definitive response saying so. That any legacy host application using ActiveX EXE library must be itself be modified to allow the use of supported languages and tools. Basically confirming that effectively ActiveX EXE is now an unsupported API interface.
I've already looked at this similar question and from it one could deduce that the answer is no but there is no definitive response. I've also looked at this Microsoft Tutorial and from what I can tell it talks about updating the host application which isn't an option in this case. The tutorial talks about switching to an ActiveX DLL but my understanding is that this would require a change to the 3rd party host application. Again that is not an option in my case. I need something that looks like an ActiveX EXE library to the host.
If you are sure that an ActiveX Exe is required, have you considered just using VB6 to create the that as a thin shim and then have it delegate all implementation to a .NET assembly? You probably would never need to recompile the Exe again, unless the 3rd party vendor is still expanding their interface.
If you post some more information about the VB6 Active X EXE library interface, I might be able to refine this solution with specific code samples. Presumably your Active X Exe must implement a provided interface?
This question already has answers here:
How to write a browser plugin?
(4 answers)
Closed 9 years ago.
In my legacy web application I need to read user system registry from JS and do some other stuff. I cannot not use ActiveX for security reasons so I have written a plugin. My Plugin consists of a DLL file which is a COM component. This COM component exposes few functions which I call from Java Script code.
In IE I package my DLL in a CAB file and install it, say it's test.dll, in the following way:
<object classid="clsid:some class id here" codebase="test.cab" height="0" width="0" onError="testInstalled=false; return true;" id="testComp"></object>
The above HTML tag install the COM component as plugin in IE and Im able to access the exposed functions of the same from my JS code:
var testCompApp = document.testComp;
testCompApp.callSomeFunction();
It works fine in IE. I need the same functionality in other browsers(Chrome,Firefox, Safari)
Can you pls suggest how to develop plugins for other browsers using my DLL file?
Thanks,
I don't get it: First you say "I can't use ActiveX for security reasons", and then you do the same bad things that ActiveX does in all its dangerous glory: a CAB-packaged COM object running unrestricted native Win32.
How does doing that solve your security concerns with ActiveX?
Leaving aside for a minute the question of "security": if you are not doing "ActiveX" already, you're pretty close. I don't remember off the top of my head all the details of what goes into [the-IE-plug-in-architecture-that-shares-with-other-stuff-the-marketing-moniker-of] "ActiveX", but I think all you are missing to be called "ActiveX" is a few interfaces you must implement. I also suspect that by being shy of "ActiveX" you don't even get to sign your CAB with Authenticode, which would provide your users with a modicum of confidence (assuming you maintain proper controls and key management, and that your users trust you enough to allow your native code to run on their computers).
In any case, that DLL you wrote will only ever run in IE. There is no other browser that supports Win32 native COM objects (whether you choose to follow the ActiveX specification to the letter or not). If you want to do the same thing in other browsers, you are going to have to rewrite it with something else.
I think you have (at most) two options for doing what you want to do:
COM/ActiveX: Native Win32 code in a COM object. What you are doing now. This only works on IE and it's extremely dangerous for users, unless it's done in a controlled environment (e.g. if this is a commercial product to be distributed by an enterprise customer's IT department, or if you have an established presence and a reputation, like some large companies do).
Java:. This would run on all browsers assuming your users have the proper runtime installed and enabled. But it will only work for you if Java allows access to the information you seek via a sandbox-authorized method, because you can't call registry API's from the Java sandbox. The same goes for "the other stuff" you need the plug-in to do.
Ok, so you have a third option:
Reimplement the whole thing in something that is not tied to the browser: a native Windows executable; maybe in a downloadable installer or maybe a .NET program deployed via ClickOnce.
You are in a pickle: You are saying "I have security concerns with running ActiveX but I need to do something dangerous". Any piece of code downloadable and runnable by a web browser that is able to access the registry directly is - necessarily - a dangerous piece of code. Any conceivable technology that allows you to run such code from a browser will immediately elicit the very same security concerns that ActiveX elicits.
Indiscriminate access to the registry is out of the question from a modern browser sandboxed environment, so you either have to find a different source for the specific information you want, or you have to use ActiveX/COM running under IE.
So I have this bit of a project planned for Windows Store and Android. Basically, a networking multi-tool coupled with a scripting engine to implement protocols and behavior. Ideal uses being things like "my embedded device uses this simplistic network protocol. I'd like to quickly prototype a way to control it from my tablet".
It's my understanding that the Android market should have no problem with this. However, the Windows Store policy includes a vague clause concerning remote code execution
3.9 All app logic must originate from, and reside in, your app package Your app must not attempt to change or extend the packaged content
through any form of dynamic inclusion of code or data that changes how
the application interacts with the Windows Runtime, or behaves with
regard to Store policy. It is not permissible, for example, to
download a remote script and subsequently execute that script in the
local context of your app package.
Of course, the scripting engine will be sandboxed and such and should be "safe"(completely intepreted, no reflection), but does it violate this policy?
If you build in your scripting engine, and only run local scripts, you will be good. However, if you were thinking to have a repository of scripts that could be downloaded and subsequently run, that would be in violation of the policy as we understand it.
Unfortunately I don't think anyone but someone on that team can answer that (or someone with direct experience in that) because of the closeness to the legal language. Have you tried the Windows Store Appl Publishing forum at: http://social.msdn.microsoft.com/Forums/en-US/windowsstore/threads
In the context of scripting engine example given, unless the app modifies the scripting engine after deployment on user's system such that the representation of protocol/behavior (the script artifact's format) is made to change then it'll be policy violation. Its as if you submit Python interpreter, and at some point in time it abruptly moves onto interpreting ecmascript.
I'm trying to find a decent standalone webserver that I can load up on a jump drive.
My wife is a photographer, and I'd like to present the clients with their images on usb. When they plug it in, I'd like a web page to load up, and run some jQuery magic to show them a nice carousel of all there images.
So far, this is all fine since it can all be done client side and doesn't need a server at all.
The problem I'm facing is that I'd like some server-side code to be able to read the images out of the directory so that once the interface is built, I don't need to manually create all of the <img /> tags.
If it was primarily going to be used in a Windows environment, I'd have no problem going with IIS Express, since I'm mainly a .NET MVC developer and this would be perfect for me... However, the fact of the matter is that a large amount of our client base is also OS X users.
I did find this Java one jlHttp, and I also found this thread here on SO, but I don't think I understand enough about either one of them to accomplish what I'm looking for.
Thanks in advance for your suggestions.
I'm looking for the same thing, and the two best options I've found were Flying Ant cd web server and Stunnix. Of the two, Flying Ant is cheaper, and I've tested it with success on my project.
I found Mongoose very convenient for this exact purpose. It's crossplatform, lightweight and requires minimum configuration. You may be interested in this project that uses Mongoose to display pictures in a folder tree or FTP directory.
How about Node.js
It says it runs on Linux, OS X, and Windows.
There was a challenging situation happened when i was working with install to provide product key validation. I had to use C++ unmanaged code to validate the key. Actually we had the main validation logic written in C# and I had to create a mixed project. Problem was not stopped only with these, it continued. Since I used VC++ code, it expected atleast the VC++ runtime redistributable to be installed in the client machine. I thought of dropping the plan to migrate our install to Wix because of these kind of problems.
But I came to know that there is a nice and very cool feature that DTF is available in Wix to integrate any kind of actions in C#. I used it and could integrate the key validation in couple of hours and till now it is working fine in all client machine I implemented before 6 month.
Do you have any interesting moment or nice experience with DTF?
Search my blog at http://blog.deploymentengineering.com for DTF and you'll find a lot of useful content. I love DTF but I still believe that the best solution is to avoid a CA whenever possible in the first place. C#, like VBScript before it, is so luring that it tends to suck imperative thinking developers into writing CAs when not needed. I believe this is the reason DTF wasn't released for so long.
At my day job my approval is required for anyone who believes they need a CA. I instruct the developers on basic MSI philosphy, how to use DTF, how to attach a debugger and I make it clear that they are on the hook if it ever has any issues. The result is very few but well written CAs in our product line.
I have written several .NET CAs to support our WiX based installs:
Managed Wrapper around HTTPAPI.DLL - supports creating IP/Port SSL bindings and HTTP Url ACLs for use in deploying WCF services. I plan to turn this one into a Wix Extension. It was very interesting learning how to properly handle rollbacks, etc.
SSL Picker dialog that displays all the SSL certificates on the system and allows you to pick one.
SQL Server browser dialog - lets you browse your network for SQL Servers and then browse SQL Servers for Databases. Optionally uses impersonation. This is for crafting a connection string.
I am in the process of writing a set of CAs that will use the Microsoft.Web.Administration assembly to do native installs of web applications on IIS 7 (without requiring the IIS 6 Metabase Compatibilty feature be installed).
First off, the C#/DTF custom actions are still custom actions (no magic here :-)), so you should follow all the various CA guidelines working with this kind as well. It simplifies most of MSI tasks by abstracting low-level API behind the high level well-designed classes. Also, keep in mind that you can use managed code CA only in case the target machine has .NET installed (or install it as a prerequisite). Finally, the dtf.chm documentation which is distributed along with WiX toolset has some simple, but self-explanatory examples.
Hope this helps.