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How to choose a Java-COM bridge? [closed]

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I have to create an application which automates Outlook and Word and I want to use Java for that task. (The only allowed alternative would be VB6, so...)
After a quick Google survey I found several libraries, but I'm not sure which one to use:
J-Interop
SWT
JACOB
COM4J
jacoZoom
...
I have no idea how to compare these libraries and make an informed decision. It seems that COM4J is a little bit outdated, JACOB leaks memory (allegedly) and jacoZoom is commercial. Each and every one seems to require a lot of boilerplate code to perform a simple method call. (Which might be unavoidable given the design of COM)
Besides that I have no idea how to choose between one of them. Which one is the best?

We use Jacob in production environment and it works out pretty well. Nevertheless the projects seems to be not very active.
Speaking of which: Activity seems to be an advantage for J-Interop. We tried the project as well and it seems to work out pretty good with even better logging messages. I think we might choose J-Interop for new projects.
COM4J seems to be outdated, you're right.

As a developer seasoned in Java/Linux but ignorant in Windows, here was my experience (August 2015)...
Executive summary:
Go with com4j... with the caveat that:
You may need to build the latest (unreleased) code to get some important recent fixes.
Longer story:
At first, the propensity for code involving JNI to crash inexplicably made me look for a non-JNI solution. J-Interop seemed to fit the bill.
However, as I tried to get j-interop to work, all the Windows DCOM permissions and registry crap made it a total PITA. It's different for different versions of Windows, required changes must be made as Administrator, etc. I don't understand any of this Windows crap and it makes me want to puke anyway.
I then tried com4j and it worked like a champ. This project is very nicely designed. It auto-generates Java interfaces from the DLL's you are using. COM calling convention details are declared using Java annotations on the interface methods, allowing you to tweak these if necessary (no tweaks were necessary in my case).
There are several developers on github who have forked the project and contributed back fixes, which is a healthy sign.
The only caveat is that you may require some of the recent fixes which, as of August 2015, are merged into the project but not contained in the latest release (which is from March 2014).
So you may need to do a custom build yourself, which includes building DLL's in Visual Studio, etc. Even as a Windows hater/ignorant, I was able to do this.

COM4J still seems to be active - it has been moved to Github and has a new homepage:
http://com4j.kohsuke.org/tutorial.html

J-Integra by Intrinsyc Software http://j-integra.intrinsyc.com/ is your best option. It hides the complexity of having to know an unfamiliar programming language. It isn't dependent on JNI so you don't need to know JNI. J-Integra is also actively maintained and supported and Intrinsyc offers a pure 64-bit version for those people wanting to run in a pure 64-bit environment.
Intrinsyc offers free trials so you can test it out and see if it works before committing to any purchasing.
Companies like HP, IBM, SAP, and Oracle use it so you know its going to be fast, stable and well supported.

Appears bridj can do some COM interop as well: https://code.google.com/p/bridj/wiki/COM#Example

Alternatives to java on android [closed]

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I just got myself an android phone and I'm dying to start coding on it !
However I'm not a big java fan, although I can live with that, I would like to know if there're reasonable alternatives for the android virtual machine.
I've done a medium sized project using clojure, however from the reviews I read, it's very slow when running on android. How about scala ? I read that some people did experiments with it in android, is it "fast enough" ? How big is the learning curve ?
Cheers,
Ze Maria

There's the NDK which allows you to write parts of your program in C or C++.
There's ASE that allows you to write scripts in python and maybe other languages. There's no python compiler despite you might hear otherwise.
I have read something about scala but since I wasn't really interested I did not pay attention.

There's definitely quite a few people doing Android development in Scala. Of particular notice, there's even a plugin for SBT, the prefered builder for Scala projects, with Android-specific targets.
As for learning curve, I can't speak for Android development itself, as I haven't done that. As for Scala, you can be productive very quick, but learning all the particularities of the language takes time. You don't need to learn all the particularities -- I have seen people write non-toy programs with barely any experience -- but some people can't stand not knowing something about the language they are using.
Also, a lot of Scala code out there is very declarative. If you look at the SBT build files, for example, they are mostly declarative. Some people get very upset by that, for some reason.
I'm guessing what I'm trying to say is that it depends mostly on you how well you'll take to Scala.
As for speed, Scala code can be as fast as Java code, though that may call for avoiding the more high level abstractions in exchange for uglier, but fast, code. It depends a lot of what kind of computation you are doing, though.

Android 2.2 adds jit to the VM which is supposed to make loading Clojure programs much more efficient. Clojure produces a lot of small classes which take a while to load when the android program starts up. this should be alleviated with the enw android though its not intolerable now.

Just noticed that some Scala examples can be found in trunk: http://lampsvn.epfl.ch/trac/scala/browser/scala/trunk/docs/android-examples.
I haven't tried myself but it's encouraging.

There's a port of JRuby to Android, as well, which I've played with and seems interesting. http://ruboto.org/

"fast enough" - you are running applications on a mobile phone that question relative to what you expect it to do.
Also java's performance has been increased through the years. But also run you are just coding in java. Google has created a tool that take java byte code and converts it to .dex (Dalvik Executables). Dalvik the VM implementation that java used is optimized for this platform. Which mean you can program in a high level language like java which provides many helper classes which means you will be more productive.
They do have a NDK but I believe you have to still have a java front end and have your java code call the NDK code when necessary. You pretty much only want to write the native code when you really need to optimization. Alot of java classes like java nio and the opengl classes are just wrappers to low lever calls that use hardware resources directly.
I probably over answered you question a little.

There is also Lua, which you can use with the Corona SDK.

Is there a way to transfer/translate the code written in Java to other languages? [closed]

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Theoretically this seems possible to me. So can Any one confirm this to me, if it's possible? and if there is such a software that does this?(like Java to C++ or C#)
And in general would it be possible to transfer languages like Java to server-side programing language like PHP?

Translating the syntactical elements of one language and producing another is not trivial but it's not impossible. A good parser can build syntax trees in one language and then emit another. The difficulty of porting code outside the context of simple "Hello World" type applications is twofold:
The libraries of one language will probably differ (e.g. WinForms vs Swing)
Some language features will have to be catered for: (lambda expressions, anonymous methods, different inheritance implementations etc).

It is possible, but the major problem is that Java has a very large runtime library which needs to be made available in the target language in order to be able to do a fully automatic conversion.
For the special case of Java -> .NET, you can use J# from Microsoft to compile it into a .NET assembly which can then be used. Also ikvm.net allows for running a JVM inside .NET.
For PHP I do not believe such a solution exist. You MAY be able to use gcj to create a native library which can be linked in, but I do not believe it is a feasible soultion.
What functionality do you need in PHP?

Visual Studio ships with a Java to C# translator, and even tough it does a pretty decent job, there's still a lot to clean up afterwards.
In my experience you really have to ask yourself if it makes sense to translate code from one language to another. What is the gain? Will the translated code be maintainable? If the answers to these questions point in the wrong direction, translating is probably not the right approach.

Google Web Toolkit does conversion from Java to JavaScript:
http://code.google.com/webtoolkit/overview.html

to answer your question, yup, theoretically this is indeed possible and practically such technology is used every day :)
The interesting thing, in my opinion, is that the Java converters typically convert by taking the bytecode, not the source code. Then it's, say, bytecode-to-ObjectiveC source code. For some converters (at least one opensource one) it's bytecode-to-XML then XML-to-target-language.
For example, the Uniwar application for the iPhone, which has been acclaimed by all and made its way to the appStore's top ten, as been written in Java (JME) and automatically converted from the Java bytecode. Reaching the top ten, even for a few days, means that this is deployed on a lot of machines ;)
In the Real-World [TM], Cobol-Java and, weirdly, Java-Cobol are not unheard of.
For all this to work that said you need a really good converter :)

Theoretically it is possible. But as others pointed out the main problem is to translate libraries.
Some time ago I made Java to Tcl(XOTcl) and Java to Python translators to evaluate the translation posibility. Search by java2tcl and yava2python.
They convert syntax but do not make relevant constructions translations (e.g. Java file operations to Python ones). That would require more development time.
In general my opinion is what such a translation may be possible. But only if your translator covers classes/libraries of the converted project.

Google App Engine -- Java or Python? [closed]

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I noticed that this was asked in the following post. Has anyone used both and can conclusively tell me which is better? It seems like python might be a little easier to implement and faster?

By this time, both implementations are reasonably mature and solid, and their functionality is pretty similar (I don't think it's quite 100% equal yet, but, moving in that direction). So, if you already know only one of the two languages, I'd say "just go for it". If you already know both, you don't need my advice;-).
If you know neither, but are rarin' to try some of the non-Java languages that are (more or less;-) supported on the JVM side of GAE (I believe this includes Scala, server-side Javascript, JRuby, etc), then it's worth trying. If you know neither, and don't want to risk a "not-first-class-supported language", I'd definitely agree with your observation that Python's faster to learn (but of course I'm biased in favor of Python;-).

I have used both, and my conclusion is that biggest difference is in libraries. In theory both have good libraries to do almost everything but in practice many libraries don't work with app engine:
All Java libraries are pure Java and should work, but as app engine does not allow threads and not even all *java.** dependencies it is... lets say problematic.
Python on the other hand have way less libraries out there, and many are just wrappers for native C libraries, which don't work either. :(
As both versions have such bad support for libraries, I call it tie. For very simple "just to show some content" -web app you don't need any external libraries of course.
I use now Python because it rules. ;)

"Better" is always subjective. For GAE, the choice of which is better for you depends on what you're most familiar with. If you've got experience with Java, use that, and if you've got experience with Python, use that. I don't think there's any objective criteria that would point to one being "better" than the other.

Its not just the language that you need to consider here. Libraries, frameworks, and tools are also relevant factors.
If you have no background in either language or web development, I would suspect Python would be easier to get off the ground with. It has been around longer, there is likely more support and knowledge available. Doing something simple is generally simple to do and the Python framework is in my opinion more lightweight.
Despite this, I would rather use Java. However, my reasons are controversial and I don't want to troll :D.

Python was the language Google AppEngine was originally designed for, and it has been supported for longer than Java (which only got included comparatively recently). Additionally, Guido van Rossum, the creator of Python, works on the Python side of AppEngine. The same can not be said about Java's creator.
It seems that there is more documentation and articles about Python on AppEngine than Java, probably because Python has been used in AppEngine for longer.
My advise: Use Python.
But that doesn't mean Java is a bad choice, because it is not, I just think Python is a better choice in this instance.

Python ( subjectively speaking )

.py chosen here for all gae projects for reasons more readable, less lines code, higher level same time java has more ways to solve a given problem. Approx estimate same function with python is 1/10 the code compared to java.

i use python, becouse always can get the best of django in appengine

I use Groovy (Grails) with GAE. It has Java's library universe and you should have roughly the same LOC compared to Python. Yeah, its not 100% Java (if you want to), but very close.
The BIG difference is roughly the JavaVM speed, that's one of the reasons Groovy (Grails) has gained so much popularity - especially people like my who dislike Python .)

It maybe possible to use Jython in appengine so you could use both. One thing I would say about the python productivity vs Java productivity argument is Java has excellent IDE's to speed up development where as Python is really lacking in this area because of its dynamic nature. So even though I prefer to use Python as a language, I don't believe it gives quite the productivity boost compared to Java when using a new framework. Also I have as yet not been able to get the python version of google app engine to work in Netbeans which is a royal pain.

Is Java the best language to develop cross-platform GUI applications? [closed]

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For "best" I intend that the code shouldn't need, or need very few, platform specific tweaks.

I strongly recommend Java for cross-platform GUI development. In particular, I recommend the GUI builder that comes with the Netbeans IDE. It's very simple and very powerful. You can point and click and drag and drop to create a GUI, and easily customize the actions which various buttons and other components take.
I much prefer Python as a language, but none of the free tools for GUI development come anywhere close to this, and the same thing seems to be true for the other languages I've used. (I should point out that QT has wonderful GUI developers for various languages such as C and Python, but it's only free when used on open source projects.)
EDIT: QT has recently been relicensed as LGPL, so you're free to use it in commercial applications. The Python bindings for this (PyQT) have not been re-licensed, but another project called PySide has been created to provide Python QT bindings.

I personally despise the whole concept of emulating the native GUI that is where the Java GUIs are rooted. Instead of being at home wherever you go, it makes you a tourist everywhere, often needing an interpreter. The Eclipse GWT is a better toolkit that makes much better use of local resources, but it still holds that people love to write Java code, and hate to use Java applications, think of it: which Java applications you love on your desktop?
Tk is just as ugly and limited on any operating system you choose to run it onto, and the same goes for Qt, in my opinion.
Mono would need a good try, as it is a way to answer the question "why Linux sucks", if you remember that old post bi Miguel de Icaza. Mono comes with a mature set of widgets and Apis and does not try to limit what you can do in order to give you portability.
Silverlight is close to portable and has a great interface definition language, but lacks access to the system, you have to split the application between a server and UI even on the same machine to overcome it.
Adobe AIR is a dog and local system acces is not easy.
If I am able to choose, I tend to avoid GUIs altogether and try to use a web server, even a local web server, and Json, JQuery and all that stuff. I found out that I can have many more choices and am more productive than with native widgets. This combines the strengths of the use of a real language server side and the wonderful disordered geniality of JavaScript in the GUI.

Yes: use Eclipse RCP. You can write not only cross-platform, but e.g. multilingual applications with it. SWT provides the native look-and-feel for multiple platforms and windowing systems.

So as I understand it, there is currently NO truly cross-platform high level language & GUI toolkit right now.
Java is cross-platform, GUIs in both SWT and Swing can look good, when you really try hard to tweak them pixel-precise and provide modifications to the look to supported platforms. There are currently some good GUI designers, but nothing as great as OpenStep 15 years ago.
QT is now LGPL'ed so long as you only link to it dynamically. Well but QT has its own set of problems and is a superset of C++. You have to compile against QT-hacked compiler, not the generic C++ one.
didn't try the wxWidgets, but from the looks of it, it can work, but is NOT high level toolkit at all!
There seems to be an option to write in C# and opensourced .NET and run it via Mono in other platforms than Windows... Didn't try, but it seems to me, that is just porting Microsoft on other platforms.
There is GNUstep, but for now it looks for me, like it is only developped by some opensource geek fans. It would be really interesting to see the OpenStep stack outside of the Mac OS X, but for now this looks to me as not viable.
Even Java, while it is self-contained, does not currently provide great GUI designer capabilities. I used the GUI designer tool once when starting to learn how to code with SWT, and now I find myself coding it by hand, which is really not bad, but it really should not be necessary. But that was few years ago, I will have to try again.
You can of course create your cross-platform application core and service code in one language (Java, or C/C++ if you want speed), creating something like a server or unix tool and just connecting to it from the GUI that you create on each desired platform using its own tools. The result is that the GUI is platform native, taking advantages of the features of the platform, and should be fairly simple to create for each desired platform. (Cocoa on Mac and .Net on windows provide rich features for the platform they are native to).
We will have to look into the robustness and matureness of such ideal solution. It should have good commercial and comunity backing and be fairly evolved right now, so as the future implementations of such tools will provide us with more than the mere LOWEST COMMON DENOMINATOR for all the supported platforms, but to leverege the cross-platform tools to include and adopt well-designed concepts and rich features native to the relevant platforms and distribute them cross-platform.
Only than can be cross-platform development truly viable and adoptable in great numbers.
Suggestions?

Java is certainly nice, but I've been doing just fine with Python and Qt via PyQt4 lately. I find that I get things done faster than I did in Swing or SWT, too.
So far, no platform-specific tweaks have been necessary, and Qt4 widgets look nice on different platforms. The Qt GUI builder is very nice, and using Python has enabled easy integration with some other cross-platform frameworks (notably VTK, scipy-cluster, and some SWIG-wrapped objects for interfacing with files output from a performance tool).
Note that Qt is not free unless you use it on open source projects.

As long as someone defines "platform independence" correctly, Java is the best.
Some people argue that C# is the best, but those people seem to misunderstand the term
"platform independence" ;)
Note: I refer to the fact that C# is ported to Linux/Unixes only as long as Microsoft and Novel keep up their treaty. The community itself would never be able to maintain such huge platform as .NET

These days there are many languages that allow you to create cross-platform GUI applications efficiently. Java, Python, Tcl/tk, C#...
I think you need to define the requirements of your application a bit more, for instance:
Will the UI be Web-based, or desktop-based?
Is the application going to be a large or a small?
Will it feature some sort of "extension" feature (e.g. plug-ins)?
Will it function over a network, and is it likely to be distributed/load balanced?
The list can go on forever, work out the defining points about your application, and start researching the language based on the whole.

I would also consider Mono as serious contender for platform independence and a good IDE tool.
Java's performance sucks on the desktop. Just check http://www.codeproject.com/KB/dotnet/RuntimePerformance.aspx

For native binaries, wxWidgets is a convenient solution.
I would tell you that is even better than Java for the user experience side. Even though you can make the presentation layer look pretty much the same for all platforms in Java, they all look like Java. On the other hand, wxWidgets make the user feel like a platform specific build (and it is, indeed), but you can use the same code to compile for several platforms (at least the major ones).

I would think that it depends on what kind of platforms you plan on targeting. Java will have the most platforms with a VM. However, if you just want to use Windows and Linux, you can use C# (using mono on linux).

Based on your definition, no. Even wit the newest graphical libraries you can expect to do a bunch of testing on different platforms.
Flash would probably be the best. Wide spread and better at looking the same across different platforms.