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IVR Development in java

I'm going to develop an on-line IVR application using Java (without PBX).
In the software requirements there are some mathematical calculations and database communication which I prefer to implement on Java side.
As you know, different technologies are ready to integrate with Java, such as JTAPI, Zanzibar OpenIVR, Moho, VoiceXML, CCXML, Jive, Prophecy, Voicent, Voxeo etc.
Now the question is: What is the best solution? Which one is easiest to reach? Which one have the best efficiency? Do you recommend Open Source frameworks? Is there any Windows API for handling IVR systems?

If you're going to do VoiceXML with Java, you should take a look at Rivr, an open-source VoiceXML dialogue engine.
Rivr let you code your callflow naturally in the Java language. Thus you can reuse all the available Java tools (e.g. debugger, unit testing framework, coverage test tool) to develop the callflow. You also benefit from all your IDE features too (refactorings, source navigation, version control, etc).
The API is very simple. You can code a complete callflow with a single method. No need to define "states" or to manipulate templates or XML files.
Integration with server-side logic is trivial since you are only coding for the server side.

There is far too little information here to provide a direct answer, but I'll try to give you some basics.
The standards for IVR application development is VoiceXML for dialog (caller interaction) and CCXML for call control. The latter is not as commonly available. There are also numerous proprietary solutions. Your choice of an open standard versus a proprietary solution should be more about vendor/solution lock in. Even with the open standards, you'll likely use custom enhancements and have some amount of lock in, but portability will be easier. You can code directly to the telephony boards (challenging and usually poorly documented if you are someone new to telephony) or work with solutions that provide end to end capability. I find very few people porting IVR applications so I would focus on supportability of your application, features and ease of use in your decision.
Platform choices run the spectrum. You have premise (onsite) and hosted solutions. You mostly have high end enterprise solutions and low end solutions. There are very few middle ground solutions. Features (telephony and integration capabilities) vary dramatically.
From a telephony perspective, take nothing for granted. In particular, transfers. There are many ways to transfer a call. How it is done will be constrained by your connection. An analog line to the CO (phone company) can have multiple mechanisms and the one in place will typically be dictated to you. Not all telephony platforms will support what you need. Hangup detection, at least on analog lines, can also catch the novice out. Hosted solutions will typically allow you to avoid most of these problems. VoIP solutions are even more complicated due to compatibility between devices (yes there are standards, lots of them, with lots of optional parts and then there are custom flavors).
For windows specifically, you can use Lync, but it is complicated...though many of the solutions you will explore will be complicated.
In short, there is no best solution. Your knowledge of the technologies, requirements and budget are going to drive the decision. I've generally worked with enterprise IVRs in on premise and hosted configurations that are typically fronting large call centers. I have come in contact with many of the open source solutions. Anything on premise is likely to be complicated because of the system and telephony configuration. Hosted solutions have typically done most of that for you.

I know that those are "de jure standards". But you should also take Asterisk(with AGI/AMI) as a consideration for your project. If you decide to try Asterisk and Java, take a look of astivetoolkit.org it may be very helpful.

Ricky from Twilio here.
For me, picking the best tool for a particular problem is one of my favorite tasks a developer. One technique to figuring this out is blocking off a day and spending an hour or two with each potential option. A few question I'll typically explore:
Which tool is the easiest to get started with?
Which tool has the best documentation?
Which tool has an engaged community that I can learn from?
I'm sure there are a ton more questions depending on your scenario you'd want to explore (Does it fit within my budget? Can I use it with the technologies I already know and love?).
If you're looking at building an IVR, we have an API that could help. We just dropped some new tutorials including a non-trivial, production ready IVR application using Java.

For improving my programming skills I want to follow "learn a new language a year". What we can learn in 2011

I want to learn a new programming language in 2011. I am a java progmrammer, with not more than a year experience. I want to learn something which is really new and exciting, but not related to mobiles (iPhone, Android, iPad, Symbian).

I would suggest that you should give Scala a try.Its a language which runs on JVM and it is very much like Java syntactically,so you can easily pick up.Python is another good option.

Learn Rich Internet Application development (RIA). This is "new and exciting", especially if you don't care about mobile stuff. This means (and both of these primary languages, C# and ActionScript, are similar enough to Java that you'll easily meet your 1 year goal):
Silverlight / WPF Language=C# and xaml (Microsoft has come a long way in a short time with this and the quality of the tools in comparison to what's out there for Java/Flex stuff is impressive.)
Adobe Flex Language=ActionScript and mxml (If you want to stay in Java this is probably your better choice. For the record, Java/Flex is my primary skill set and has been for years, but as I've said above, their .NET equals are very attractive nowadays and I'm starting to learn C#/WPF/Silverlight now as a result.)
(JavaFX perhaps also, but I've never used it and it's widely not considered as mature as the other two.)
Techs like these are very well suited to controlled environments such as the business world (internal intranets) where it's easy to push out Flash player or Silverlight to all workstations you need it on. (So it's nice on a resume if you're job seeking.) In the Internet world it's a little more iffy, but still not too bad since deployment rates for Flash 9+ are pretty good now, and Silverlights are quickly rising as well.
"AJAX" and all it's dependent "stuff" (DHTML, DOM, CSS, etc etc) is common, but I wouldn't consider it new or particularly exciting. It's a bigger deal in the mobile scene where a lot of hardware either can't run more advanced virtual machine environments or they're intentionally crippled in an attempt to prevent this (Apple products).

Google created a new language this year called "Go". You could give that a try.
From the Go home page:
The Go programming language is an open
source project to make programmers
more productive. Go is expressive,
concise, clean, and efficient. Its
concurrency mechanisms make it easy to
write programs that get the most out
of multicore and networked machines,
while its novel type system enables
flexible and modular program
construction. Go compiles quickly to
machine code yet has the convenience
of garbage collection and the power of
run-time reflection. It's a fast,
statically typed, compiled language
that feels like a dynamically typed,
interpreted language.
http://golang.org/

I want to learn something which is really new and exciting, but not related to mobiles (iPhone, Android, iPad, Symbian).
How about something completely esoteric and not very useful, such as a Turing tarpit language like brainf**k?

Have a look at nodejs!
http://nodejs.org/
http://en.wikipedia.org/wiki/Nodejs

If you want to explore some new stuff but still be close to java, start learning Scala. It's a great JVM-based language, almost as fast as java, but with tons of new features. It mixes object-oriented and functional programming. Functional programming is gaining more popularity now, because of scalability and concurrency, so it's better to stay close to it. You can also learn about concurrency in a more natural way with Scala.
If you want to go into web-development, Ruby and Rails is a good choice.

Learn D, and if you really like it, help make the compiler better! D has practically every single feature you can think of, and then some (you can read about it on the website, I won't list things here), and it's much more powerful than C++ in some ways (it certainly isn't less powerful in any way except--maybe--for the lack of multiple inheritance, which I personally don't like anyway). The only thing it really lacks right now is a good, bug-free compiler, but for the most part it's just purely amazing. Just look at its features and you'll see. :)

jQuery, what about platforms such as AJAX and MVC? Kind of depends on what you already know and which platforms you're targeting.

I find visual material much more appealing to learn from, like video tutorials, etc. But theres tons of stuff, like reading tons of blogs, or if u dont have the time, download the pod cast so you listen on your way work (which what I sometimes do).
Basically you have to be displined in making time to learn, and you will always be on top of most things.
Sk8tz

Jar Store - prevent from copying

We are going to create Jar Store the way like App Store works, but for Java Developers.
Everyone will able to submit and sell custom .jar library which solves some little problem, but solves it very good to save other developer's work time.
The only undecided question is how to prevent .jar copying or publishing bought .jar to the Net.
EDIT: This can probably achieved by using strong copyright policy? Suggest please!
EDIT 2: I imagine Steve Jobs asking:
How we can prevent iPhone Apps from copying?
— You can't it's just a files on the iPhone which can be easily copied by anyone.

Whoa! Did we just go through a 12-year time warp?
This is exactly what JavaBeans was intended to do, back in 1996-7.
It was intended to solve a technical challenge of pluggable, re-usable code, which would of course engender a vibrant and lucrative third-party marketplace of drop-in components. People would make,sell, buy, and consume these re-usable pieces of code.
Then, that fantasy was replicated when server-side Java grew in popularity. The idea behind numerous companies was that they'd act as brokers and commercial exchanges for re-usable pieces of code. The names of these companies escape me now. There were many.
Most of them faded, and some of them evolved their business model away from acting as an commercial exchange, and towards selling software directly. In particular, they moved toward selling the thing they had hoped to run their business on (their "ERP"), as a piece of software that enterprises could use internally - a component repository supporting re-use within an enterprise.
Darn! The names of the big companies that made this transition escape me now.
An interesting question is, why did App Store succeed (wildly!) while the vision for JavaBeans stores, or stores for enterprise Javva components, never caught on.
I have my theories but... not least among the reasons is the phenomenon of "open source" - where you can get pretty darn good re-usable components for free. Before you go tilting at this windmill, I suggest you study some industry history!

For this to work you need to have content. Really good content. With excellent documentation.
I would imagine this is the first obstacle you need to tackle.

With this business idea copyright protection in both technical and legal way must be you core competences since this is the main part for your added value.
If you prevent something from copying, how are people supposed to distribute their software? I'm not writing enterprise solutions to run only on my notebook.

you can't don't even spend any more time on trying.
rephrase your question to
I want to restrict someone copying a
plain text file.
Same problem with a .jar file. You can put all the legal restrictions you want, but it won't stop anyone from making a copy of your file if they are able to use it. Go ask the RIAA how effective they are at stopping the copying of .mp3 files.
I would also offer what do you think you can offer than the Open Source community doesn't already offer in the Java world? The Java ecosystem is very mature and very full featured from a library stand point. I can't imagine that anything you offer, that might be the least bit innovative, some open source project won't spring up and create a free open source version of.

NetLogo vs. Repast Simphony? [closed]

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I would like to simulate some scenarios using the multiagent
paradigm, and it seems NetLogo and Repast are the most popular tools for that.
I'd like to know if anyone has had any experience with either one and could tell me more about them? For example, I've noticed that there is a fluxogram-like modeling option for Repast, but I believe it is rather limited. I've looked around the tutorials and documentation in the official site, and the documentation seems to be lacking. While there are some examples with it, I'd say extending it to simulate an ambient which it has not been specifically prepared to seems like an unreachable goal at the moment, despite Repast obviously being very robust and apparently able to handle it, given enough familiarity with it.
On the other hand, NetLogo has more examples and overall I've liked it more for its simplicity, but it seems to be more focused on the simulating propagation of diseases or similar models. I've found a programming book teaching Logo, so I figure it'd be easier to get started with it too.
Currently, I am thinking of simulating botnets and IDSes as multiagents. The problem, however, is that I would have to abstract the network and transport layers to an extent to be able to do it, as well as generate traffic between the nodes. Repast is apparently more fitting for this, but given its complexity and lack of documentation I'm thinking of using NetLogo. While there are some examples of NetLogo with traditional applications (ex: Tetris or Pac-Man), I'm not sure about how appropriate it'd be for that.

I have a webpage with a couple dozed netlogo multiagent simulations. I use netlogo for teaching and I have found that, once you get past the learning curve, you can develop simulations amazingly fast. Stuff that would take you 80 man-hours in other so-called agent environments (Jade, Repast, which are really mostly just programming libraries) can be done in 2 hours.
On the other hand, netlogo is not really good for simulations that require immense amount of details, like say simulating a network all the way from TCP/IP to HTTP. That would just require large amounts of code, regardless of programming language, and netlogo currently sucks if your program ends up being more that 10 pages long. Having said that, most people would be amazed at what you can get done in 10 pages of netlogo code.

Short answer: it depends on the programming paradigm or language you want to use, and the design you want for your agents:
If you want a low-entry-high-ceiling language allowing quick prototyping but sophisticated simulations, and are willing to learn a new paradigm (avoiding loops) use NetLogo. Good documentation.
If you want to make a real application to use on highly-parallelized clusters or just want to use Java Groovy or need a specific Java library for your purpose, use Repast or better Repast for High Performance Computing (but avoid ReLogo which is very slow). Mild documentation.
If you want to model cognitive agents (instead of reactive) with FIPA communications, better use Jason or better JaCaMo which supports AgentSpeak + Java (so you can also use your favourite Java libraries), and there's no Groovy required. Bad documentation (a lot of non detailed features and commands and bad too-complex-not-commented examples).
Long answer:
Disclaimer: I am more experienced with NetLogo but I also used Repast and a few others like Jason.
Basically, the difference between NetLogo and Repast is that with NetLogo you will have a simpler framework but you'll need to learn how to program in a turtle-and-patch-oriented paradigm, while in Repast you will have to learn that + the mechanisms behind Java Groovy but you will eventually get more flexibility. Speed isn't really a criteria here (see below).
To be more clear, you can program efficiently in NetLogo if you use to a maximum the turtles and the patchs native functions. For example, if you want to implement A*, instead of implementing a list of nodes, you should directly use the patchs and filter them using stuffs like this:
ask patchs with [criteria1 = value and criteria2 = value2] [do-some-stuff]
ask patchs with-min [criteria][do]
let var [somevalue] of min-one-of patches [criteria]
Also if you can't find a way to efficiently do what you want, be sure to check if maybe an extension exists (check also here under Libraries and Tools) for your purpose, like the now native matrix extension which allowed me to make an efficient neural network in NetLogo.
On the other hand, Repast is potentially more flexible than NetLogo (since you have access to the whole range of Java libraries), but a bit more complex since you have to know how to handle Groovy.
If you are solely interested in speed, do NOT use ReLogo (NetLogo-like syntax for Repast) which has been shown to be a whole lot slower than NetLogo (see the 2012 paper below). In any cases, your best bet would either to try an implementation with NetLogo using the tricks above, or if you want to use your application for real later, there is also a distribution called Repast for High Performance Computing which removes most of the overload that come with turtles and patchs objects, and thus it can be used for real applications. A similar extension exists for NetLogo to compute in clusters with parallelization but it's not an official distribution.
If you want more infos about the diverse platforms, here is a nice review of 2006:
Railsback, S. F., Lytinen, S. L., & Jackson, S. K. (2006). Agent-based Simulation Platforms: Review and Development Recommendations. SIMULATION, 82(9), 609-623.
And an updated version of this paper in 2012 dealing with NetLogo vs ReLogo:
Lytinen, S. L., & Railsback, S. F. (2012, April). The evolution of agent-based simulation platforms: A review of netlogo 5.0 and relogo. In Proceedings of the Fourth International Symposium on Agent-Based Modeling and Simulation.
/EDIT: I cited Jason but didn't give any more details. If you want to model cognitive agents (instead of reactive agents), you can do that in NetLogo using the unofficial BDI extension which works well but is a bit limited (but it's easily extensible since it's pure NetLogo), but your best bet is to use a framework specifically designed to model cognitive agent with full support of AgentSpeak.
Jason is very nice since you have access to a full AgentSpeak language + JAVA to implement the technical side. In fact, you can do whole projects using only AgentSpeak (which I did), but you can also make more Java-oriented versions, it's up to you how you want to design your program, the result will be more or less the same. This offers you a lot of flexibility in your design workflow.
Tip: search for "Jason internal actions" in the documentation to get a good description of the available AgentSpeak commands.
Also if you are interested in Jason, you might be interested in JaCaMo (= Jason + Cartago + Moise) which is the result of a cooperation of three projects authors to make a full-fledged cognitive agents framework which also can model complex environments (with artifacts theory) and multi-agents organisations (roles, groups, missions, etc.).
A last framework I know of but didn't have a chance to try is Mason which supports 2D and 3D environments. Never had a chance to try this one so I don't know how this compares with the others but you can try it out.

Here's a generic comparison.
http://www.duncanrobertson.com/research/AMLE.pdf

I had more or less the same problem a few months ago when I had to choose a framework for my simulation. I look at Repast, NetLogo, Swarm and Jade.
NetLogo was nice and I tried to write some simple test applications but since I wanted to use Java as my programming language, NetLogo wasn't the best candidate. Repast has pretty much everything you need to write larger simulations and there are many projects (especially in social sciences) where Repast is used. My problems with Repasts were: bad API documentation, parameters that are passed to methods or constructers that are never used and don't make any sense at all (have a look at the source code) and a lot of boilerplate code.
I'm using Jade (http://jade.tilab.com/) now and I'm really happy with it. The community is good and their mailing list is VERY active. Okay, Jade is just a library and a framework for agent-based modelling. You don't get anything like those visual editor in Repast and you'll have to write your own tool for visualising the results.
Cheers

You could simulate the traffic using a agent type called "packet" that will be spawned and send from a agent called "bot" to another agent called "bot" or "server". Instead of sending the packets to a IP address, you would be sending them to a pair of X and Y coordinates.
Netlogo has an example of how a virus spreads in a network, this might be a good starting point.

I have never tried NetLogo, but have I tried Repast-J and Simphony. It seems Simphony is good, but at the moment I am stuck at changing the Edge type from straight line to curved one. There is not enough documentation and examples available.
Once I tried Mason which is based on java, too. It is similar to Repast-J, yet it was faster. But recently there is not much development in Mason.
I would like to try out Jade later.

If you can already code in Java, you can also look at the following paper for a comparison between RePast, Swarm, Quicksilver, and VSEit, different freely available programming libraries for support of social scientific agent based computer simulation
Tobias, Robert, and Carole Hofmann. "Evaluation of free Java-libraries for social-scientific agent based simulation." Journal of Artificial Societies and Social Simulation 7.1 (2004).
Repast is definitely more flexible than NetLogo but the documentation is not very detailed for RePast Symphony

PowerBuilder for a Java programmer?

A friend of mine uses in his company an ERP software written in PowerBuilder. Unfortunately the (one and only) developer is going into retirement soon. My friend really likes the software and wants to keep using it for at least ten more years, so my friend decided to buy the source code.
He wants to start a business to maintain the software and develop new features. At the moment there are probably about 50 installations of that software out in the wild and he already knows of a bunch of potential buyers.
Now he's searching for a developer and asked me... I did a little C/C++ programming, a bit of VB and a bunch of other languages but in the last years I earned my money by writing Java web applications.
From what I read, PowerBuilder looks quite antiquated to me, there are hardly any tutorials out there, no open source frameworks, awkward version control, didn't even read about any test frameworks. People here on StackOverflow say they hope, the language/IDE is dead. Additionally the code I'd maintain is completely undocumented and untested.
Do you think it's possible, for someone who never even heard of PowerBuilder before, to maintain such a software?
EDIT: okay, thanks for your answers. We decided to kick the old application completely and re-write it in an up-to-date-language.

Yes, it's possible. Powerbuilder is not a hard language to pick up, particularly if you have used VB already.
The Powerbuilder community is far smaller than what you may be used to with e.g. Java, but it does exist. The best place (other than SO!) to ask questions are the sybase.public.powerbuilder.* newsgroups.
For unit testing, try PowerUnit, and for source control, you can use Subversion via PBSCCProxy, TamTam SVN SCC, or PushOK SVN SCC proxy.
It's been a niche language for a long time now. In my opinion this is due the upfront cost of the tools required, which is essentially blocking anyone new from considering it.
The future is reasonably bright though: Sybase is flourishing, committed to PowerBuilder, and regularly announcing progress towards version 12, which will be a full .NET language like C# and VB.NET, and will ship with an IDE based on VisualStudio. You will be able to directly migrate your code to version 12, no rewrites required.

I started my career as a PowerBuilder developer, but quickly changed to java and python, as soon as I realized PB was almost a dead language.
Also, even if there are tools that can be used to apply programming "good practices", they are not widely known and somewhat expensive, so I've had to work even without version control (!!), left aside automated testing or continuous integration.
It is a language in which almost anyone can start to build usable apps in a short period of time and with little training, and the apps are built really fast, in contrast with java, that demands a period of learning until a developer can be productive, and even then, a webapp takes time to be developed.
But the payback is with maintenance, that quickly becomes a nightmare. Even a minor change in the database like a type change in a database column can destroy every datawindow (the PB ubiquitous data-access component) that refers to it.
It's pretty much similar to VB, in that as almost anyone can develop applications in it, with very little programming knowledge, the average quality of applications is very low, with unmanageable database coupling and plagued of bad coding practices.
My advice is not to build a Developer career in such kind of language unless the money justifies it, and in that case, continue training yourself in alternative technologies as a "plan b" to not become obsolete along with the language.
And always work to keep your coding and problem solving skills "in good shape" as this kind of language does not help in that.

Yes, any competent programmer, and even some not-so-competent ones can use PowerBuilder. However, I'd disagree somewhat with one of the earlier answers. It is different from pre-.Net VB in one sense: it supports true OO principles (encapsulation, inheritance, and inclusional polymorphism [but not operational polymorphism via Interfaces as in C# and Java]). Classic VB didn't have inheritance.
Other answers from Paul Lefebvre and Colin Pickard are correct: PB is still alive though more of a niche language than it used to be, and Sybase is indeed moving it in the direction of .Net. As for source control, PB supports some interfaces (we use it with VSS) but I'm thankful for Colin's nice set of links, which may come in handy in the future.
Frameworks: the most common one is the PowerBuilder Foundation Class, which Sybase open sourced years ago.
My caveat to you is this: I said above that people didn't have to be particularly strong programmers to write PB. PB is easy to learn but takes time to master. It had its biggest days in the late 90's, when anyone that could double-click on a Windows icon to launch an app thought they were a programmer. Despite truly supporting OO, most PB apps are not well designed and well written apps. They're usually total hack jobs (a criticism of the lack of experienced developers and immaturity of software development at the time, not of PB itself, which is still a very powerful tool). If you are inheriting a code base that is truly easy to maintain and manage, you are in the minority. PB code can nearly always be classified as legacy code. The good news is that there is plenty of challenge. You will have many quick-win refactoring opportunities and plenty of production support.

With the risk of sounding biased I think PB is one of the better RAD tools out there and the new version PB12 scheduled next year will make it once again interesting since it uses the VSShell from Visual studio as its new IDE (Intellisense etc). I am currently busy working in the compiler team adding all the .NET goodies to PowerScript that one is used to from C# like delegates, interfaces, attributes etc but still keeping the language simple to use. PB is also one of the few development platforms that provide migration from older to newer versions and the new PB12 is no exception. The applications generated by PB12 will be modern looking using WPF and later Silverlight for post PB12 so I am quite excited. I am not a PB developer per se (C++) but I still think for producing C/S apps fast its hard to beat.

It depends on the technical quality of the original application whether migrate to another language is feasible at all.
BEFORE YOU READ MY "PB IS GOOOD": I'm a PowerBuilder developer since '93. PowerBuilder is very much alive and kicking. Yes a lot of people left the language shortly after the millenium but quite a few have returned later. No I don't earn money selling PB!
The biggest differentiator between PowerBuilder applications and any other tool is the DataWindow technology. It is such a strong tool in the hands of an knowledgeable developer. Examples: Dynamic creation of optimal SQL for INSERT/UPDATE/DELETE. Close to every property of everything can be an expression using data in the DW buffers. DropDown DWs are so cool. DW and the rest of PB is truly DBMS independent!
How important is code completion when many of my DataWindows only need 4 function calls anyway?
Define DB connection >> dwData.SetTransObject(SQLCA)
Read all data from DB >> dwData.Retrieve()
Write data to DB >> dwData.Update(true, false)
Reset when committed >> dwData.ResetUpdate( )
My bet: If the original developers knew how to really exploit DataWindows - any estimates you make on migration to Java or C# will not even come close to what will actually happen. If they didn't: The application is just another application that does data binding differently than your new tool.
What you loose when using PowerBuilder? You need to accept that the 4GL and its VM are designed as they are - no access to the source code of the VM so you can't make your own VM customizations. No turning off the NULL support to increase speed. No changing the event order by rewriting the VM's event manager. 4GL means less lines of code. DataWindow means a lot less LOC. 4GL means less geaky bit tweaking.
/MicKr-
BTW: PocketBuilder is PB for Windows Mobile - cool idea!

Yes, you would certainly be able to learn PowerBuilder. Whether you want to is a question only you can answer, though.
I used PowerBuilder for many, many years (versions 4 through 9). There were parts I truly liked. It's a great way to build business applications. It's object-oriented and the DataWindow is a wonderful technology.
But it has its bad points as well. The IDE is archaic. The code editor is simplistic (no code completion, for example). Integration with source control is annoying and the community is pretty small. And it's Windows-only.
There is a magazine (PowerBuilder Developer's Journal - SYSCON), but it's pretty thin these days. Sybase does appear to have some neat things up their sleeves for future versions of PowerBuilder, however.
Personally, I liked it enough that I would go back to it if an opportunity arose.

I worked on powerbuilder quite sometime back, version 6.5
Its quite easy to use and one can compare it to VB.
I feel it would be quite easy to maintain an application and do small fixes and enhance the system.
There are quite a few companies that still use powerbuilder and maintain old application.

Powerbuilder is very easy, and you will find datawindows objects very helpfull to make reports, interfaces, forms, etc..
If you know visual basic, it will be easier
i learned powerbuilder in 2 months.
A disadvantage of powerbuilder is the cost per license.