How to get the exact edition of a JetBrains IDE from a plugin? - kotlin

I'm developing a plugin for all JetBrains IDEs.
The plugin needs to know which exact flavor of JetBrains IDE it's running, some sort of string like "IntelliJ IDEA Ultimate", or "PyCharm Educational".
ApplicationInfo has some vague references to the IDE edition like /idea_community_about.png as the aboutImageUrl property but there doesn't appear to be anything concrete. Is there a standard way to get this data?

To get this information about the IDE, use
ApplicationNamesInfo.getInstance().fullProductNameWithEdition
From the doc string in the source:
Returns full product name with edition. Vendor prefix is not included.
Use only when omitting an edition may potentially cause a confusion.
Example #1: include the edition in generated shortcuts, since a user may have several editions installed.
Example #2: exclude the edition from "Restart ...?" confirmation, as it only hampers readability.
Rarely needed, consider using getFullProductName() instead.
As mentioned here: if you only need to know whether you are dealing with IntelliJ or PyCharm (Community or Professional does not matter) it is often enough to use fullProductName instead.

Related

Where is the UML Diagram option in IntelliJ?

I am trying to generate a diagram from IntelliJ 14. It is told in the documentation to install the UML Support plugin. I do not find a such plugin on my computer:
What am I missing?
The solution is: don't use the community edition. It is limited in respect to diagram options.
As I also mentioned here:
The community edition only supports a limited number of plugins. The
class diagram plugin is only supported in the Ultimate edition if I
remember correctly.
You can always try a 30-day free trial of IntelliJ Ultimate in order
to generate your class diagrams.
I recall reading that one has to pay for IntelliJ to get that functionality. It is not in the free version.
I use Code Iris and PlantUML. It is a very useful tools especially PlantUML. Other tools of this type in the IDEA are paid.
Below PlantUML.
I hope it will help you.

Any SQL formatter plugin for Eclipse avaialble?

I am not finding any standard open source sql formatter eclipse plugin on net. I am using eclipse helios. I can find Edit-->FormatSQL but that does not seems to be working. Found one at http://ventralnet.blogspot.in/2010/11/sql-beautifier-eclipse-plugin.html
but formatting is not good. Any suggestion will be helpful. For info I am using sqlserver sql scripts.
Toad eclipse-extension (community edition), will get you almost everything you want in an SQL editor, including formatting (ctrl+shif+f). Search for 'toad' in eclipse market place. It has very good Oracle, MySQL and PostgreSQL support.
Take a look at Installation instructions and screenshots.
Another option is http://dbeaver.jkiss.org/download/#eclipse (Which is very good and also has a standalone version)
Some of my favorites are:
Eclipse SQL Explorer at: http://eclipsesql.sourceforge.net
DBViewer at: http://www.ne.jp/asahi/zigen/home/plugin/dbviewer/about_en.html

Why use an IDE? [closed]

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This may be too opinionated, but what I'm trying to understand why some companies mandate the use of an IDE. In college all I used was vim, although on occasion I used netbeans for use with Java. Netbeans was nice because it did code completion and had some nice templates for configuration of some the stranger services I tried.
Now that my friends are working at big companies, they are telling me that they are required to use eclipse or visual studio, but no one can seem to give a good reason why.
Can someone explain to me why companies force their developers into restricted development environments?
IDE vs Notepad
I've written code in lots of different IDEs and occasionally in notepad. You may totally love notepad, but at some point using notepad is industrial sabatoge, kind of like hiring a gardener who shows up with a spoon instead of a shovel and a thimble instead of a bucket. (But who knows, maybe the most beautiful garden can be made with a spoon and a thimble, but it sure isn't going to be fast)
IDE A vs IDE B
Some IDE's have team and management features. For example, in Visual Studio, there is a screen that finds all the TODO: lines in source code. This allows for a different workflow that may or may not exist in other IDEs. Ditto for source control integration, static code analysis, etc.
IDE old vs IDE new
Big organizations are slow to change. Not really a programming related problem.
Because companies standardize on tools, as well as platforms--if your choice of tools is in conflict with their standards then you can either object, silently use your tool, or use the required tool.
All three are valid; provided your alternative doesn't cause other team-members issues, and provided that you have a valid argument to make (not just whining).
For example: I develop in Visual Studio 2008 as required by work, but use VS2010 whenever possible. Solutions/Projects saved in 2010 can't be opened in 2008 without some manual finagling--so I can't use the tool of my choice because it would cause friction for other developers. We also are required to produce code according to documented standards which are enforced by Resharper and StyleCop--if I switched to a different IDE I would have more difficulty in ensuring the code I produced was up to our standards.
If you're good at using vim and know everything there is to know about it, then there is no reason to switch to an IDE. That said, many IDEs will have lots of useful features that come standard. Maintaining an install of Eclipse is a lot easier than maintaining an install of Vim with plugins X, Y, and Z in order to simulate the same capabilities.
IntelliSense is incredibly useful. I realize that vim has all sorts of auto-completion, but it doesn't give me a list of overloaded methods and argument hints.
Multiple panes to provide class hierarchies/outlines, API reference, console output, etc.. can provide you more information than is available in just multiple text buffers. Yes, I know that you have the quickfix window, but sometimes it's just not enough.
Compile as you type. This doesn't quite work for C++, but is really nice in Java and C#. As soon as I type a line, I'll get feedback on correctness. I'm not arrogant enough as a programmer to assume that I never make syntax errors, or type errors, or forget to have a try/catch, or... (the list goes on)
And the most important of all...
Integrated Debuggers. Double click to set a break point, right click on a variable to set a watch, have a separate pane for changing values on the fly, detailed exception handling all within the same program.
I love vim, and will use it for simple things, or when I want to run a macro, or am stuck with C code. But for more complicated tasks, I'll fire up Eclipse/Visual Studio/Wing.
Sufficiently bad developers are greatly assisted by the adoption of an appropriately-configured IDE. It takes a lot of extra time to help each snowflake through his own custom development environment; if somebody doesn't have the chops to maintain their own dev environment independently, it gets very expensive to support them.
Corporate IT shops are very bad at telling the difference between "sufficiently bad" and "sufficiently good" developers. So they just make everybody do the same thing.
Disclaimer: I use Eclipse and love it.
Theoretically, it would decrease the amount of training needed to get an unexperienced developer to deal with the problems of a particular IDE if all the team uses that one tool.
Anyway, most of the top companies don't force developers to use some specific IDE for now...
I agree with this last way of thinking: You don't need your team to master one particular tool, having team knowledge in many will improve your likelyhood to know better ways to solve a particular roblems.
For me, I use Visual Studio with ReSharper. I cannot be nearly as productive (in .Net) without it. At least, nobody has ever shown me a way to be more productive... Vim, that is great. You can run Vim inside of Visual Studio + R# and get all the niceties that the IDE provides, like code navigation, code completion and refactoring.
Same reason we use a hammer to nail things instead of rocks. It's a better tool.
Now if you are asking why you are forced to use a specific IDE over another, well that's a different topic.
A place that uses .NET will use Visual Studio 99% of the time, at least that's what I've seen. And I haven't found anything out there that is better than Visual Studio for writing .NET applications.
There is much more than code completion into an IDE:
debugging facilities
XML validation
management of servers
automatic imports
syntax checking
graphical modeling
support of popular technologies like Hibernate, TestNG or Spring
integration of source code management
indexing of file names for quick opening
follow "links" in code: implementation, declaration
integration of source code control
searching for classes or methods
code formatting
process monitoring
one click/button debugging/building
method/variable/field/... renaming
etc
Nothing to do with incompetence from the programmers. Anybody would be A LOT less productive using vim for developing a big Java EE application.
How big were you projects at college? A couple of classes in a couple of files? Or rather a couple of hundreds of classes in a couple of hundreds of files?
Today I had the "honor" of looking at a file in a rather large project where the programmer opted to use vi (yes vi, not vim) and a handcrafted commandline compiler call (no make). The file contained on function spanning about 900 lines with a series of if-else-if-else-constructs (because that way you have all your code in one place!!!!!!). Macho-Programmer at his finest.
OK there are very good reasons for enforcing a particular toolset within a production environment:
Companies want to standardize everything so that if an employee leaves they can replace that person with minimal effort.
Commercial IDEs provide a complex enough environment to support a single interface for a variety of development needs and supporting varying levels of code access. For instance the same file-set could be used by the developer, by non-programmers (graphics designers etc.) and document writers.
Combine this with integrated version control and code management without the need of someone learning a particular version control system, all of a sudden IDEs start to look nicer and nicer.
It also streamlines maintenance of build systems in a multi-homed environment.
IDEs are easier to give tutorials to via phone or video, and probably come with those.
etc. etc. and so forth.
The business decision making behind enforcing a standardized environment goes beyond the preference of a single programmer or for that matter perhaps the understanding of the programming team.
Using an IDE helps an employee to work with huge projects with minimal training. Learn a few key combos - and you will comfortably work with multi-thousand-file project in Eclipse, IDE handles most of the work for you under the hood. Just imagine how many years of learning it takes to feel comfortable developing such projects in Vim.
Besides, with an IDE it is easy to support common coding standards across the entire team: just set a couple of options and an IDE will force you to write code in a standardized way.
Plus, IDE gives a few added bonuses like refactoring tools (especially good in Eclipse), integrated debugging (especially good in Visual Studio), intellisense, integrated unit tests, integrated version control system etc.
The advantages and disadvantages of using an IDE also greatly depends on the development platform. Some platforms are geared towards the use of IDEs, others are not. As a rule of thumb, you should use IDE for Java and .Net development (unless you're extremely advanced); you should not use IDE for ruby, python, perl, LISP etc development (unless you're extremely new to these languages and associated frameworks).
Features like these aren't available in vim:
Refactoring
Integrated debuggers
Knowing your code base as an integrated whole (e.g., change a Java class name; have the change reflected in a Spring XML configuration)
Being able to run an app server right inside the IDE so you can deploy and debug your code.
Those are the reasons I choose IntelliJ. I could go back to sticks and bones, but I'd be a lot less productive.
As said before, the question about using an IDE is basicaly productivity. However there is some questions that should be considered by the company when choosing a specific IDE. that includes:
Company culture
Standardize use of tool, making it accessible for all developers. That easies training, reduces costs and improve the speed of learn curve.
Requirements from specific contract. As an example, there are some development packages that are fully supported (i.e. plugins) by some IDE and not by anothers. So, if you are working with the support contract you will want to work with the supported IDE. A concrete example is when you are working with not common OS like VxWorks, where you can work with the Workbench (that truely is an eclipse with lot of specific plugins for eclipse).
Company policy (and also I include the restriction on company budget)
Documentation relating to the IDE
Comunity (A strong one can contribute and develop still further the IDE and help you with your doubts)
Installed Base (no one wants to be the only human to use that IDE on the world)
Support from manufacturers (an IDE about to be discontinued probably will not be a good option)
Requirements from the IDE. (i.e. cross platform or hardware requirements that are incompatible with some machines of the company)
Of course, there is a lot more. However, I think that this short list help you to see that there is some decisions that are not so easy to take, when we are talking about money and some greater companies.
And if you start using your own IDE think what mess will be when another developer start doing maintenance into your code. How do you think will the application be signed at the version manager ? Now think about a company with 30+ developers each using its own IDE (each with its own configuration files, version and all that stuff)...
http://xkcd.com/378/
Real programmers use the best tools available to get the job done. Some companies have licenses for tools but there's nothing saying you can't license/use another IDE and then just have the other IDE open to copy/paste what you've done in your local IDE.
The question is a bit open-ended, perhaps you can make it community wiki...
As you point out, the IDE can be useful, or even a must have, for some operations, like refactoring, or even project exploring: I use Eclipse at my work, on Java projects, and I find very useful to get a list of all occurrences of the usage of a public method or a class in a project. Likely, I appreciate to be able to rename it from where it is defined, and having all these occurrences automatically updated.
The fact I have the JavaDoc displayed when hovering over a name is very nice too. Like autocompletion, jump to a class name, etc.
And, of course, debugging facilities...
Now, usage of Eclipse isn't mandatory in our shop! Some years ago, some people used the Delphi IDE (forgot its name), I tried NetBeans, etc. But I think we de facto standardized on Eclipse, but it was a natural evolution rather than a company policy. And we often just open files in a text editor when we need a quick update...

Which IDE for Scala 2.8? [closed]

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This is the same question for older version of Scala, but they say that Eclipse plugin has been improved vastly. Is it the best IDE now? How do different Scala IDE compare today?
I've been pretty successful with IDEA 9. I've briefly tried both Netbeans and Eclipse and wasn't able to get what I wanted. Eclipse's code-complete didn't behave as well as I'd have liked, and I couldn't find a way to make Netbeans handle Scala scripts; It'd just complain that the file wasn't a class.
To be clear, I've been using IDEA for a few years for Java, so keep that in mind:)
For the moment, Scala Plugin in IntelliJ IDEA is the best. It handles Scala 2.8 well. IntelliJ IDEA Community Edition is now free and open source (and works with Scala), so I can't see any reason for not using it.
The plugin is still somewhat buggy (many "false negatives", i.e. the code without red underscores may not compile successfully; but almost no "false positives"), but perfectly usable. The best thing is that you can use IDEA's excellent debugger with Scala (not without some issues, but it actually works!).
FSC (Fast Scala Compiler) is also supported in latest builds. A huge time-saver.
The plugin development team is quite responsive. Some of the guys work directly in JetBrains and possess intimate knowledge about IDEA platform, so the development progresses fast.
JetBrains IDEA's Scala plug-in handles 2.7 and 2.8 equally well.
I cannot make any comparisons because I have used only IDEA.
Using Eclipse Helios with the dev-version of the new Scala(2.8) plugin, as there isn't an official release yet. That is beta, definitively -- but I can't confirm the frequently expressed opinion that this plugin is outright horrible ;-)
I'd say, the experience is already OK-ish, and indeed better than the current state of affairs with the Groovy plugin. OTOH, the experience with plain Java is way more smooth (feels like flying at times), and the current CDT I'd rate somewhat in between.
Incremental compile and error highlighting work quite well for me; tweaking a DSL implementation into form just by continuously rewriting your code until the error markers are gone -- without ever having to test-run your program -- is outright fun and just again shows that FP / static typing rocks!
Problems encountered from time to time:
- implicits and nested types in other compilation units (esp. nested / super packages) aren't picked up at times when there are still other errors around; they will be picked up after an full build
- there seems to be a memory leak in the version I'm using right now (from end august 2010), necessitating to restart the workbench after some hours of work
- beware when you're using AspectJ, to make sure you get a version of the Scala plugin which relies on a JDT weaving bundle version which also works with AJDT
PS: I'm using maven builds in all my projects and generated the eclipse projects with the eclipse-maven-plugin, and then imported them as plain-flat eclipse projects. I can just strongly recommend everyone to keep away from the M2-eclipse plugin (for maven) in its current (2010) state, it makes your workbench painfully slow, is buggy and has lots of almost unpredictable behaviour, because it constantly tries to do magic things behind the scenes (and besides that, the aspectj support is broken since this spring)
i use both eclipse and IDEA
eclipse supports type detection is
better than IDEA (it is very
neccessery thing if you want program
in functional style that you can be
aware from type of expressions and
variables.)
Edit1: IDEA supports type detection like eclipse but you have
to define a value in your functions
for example: def
testTs[A](a:List[String],b:List[A])
= for{
ai <- a
bi <- b
} yield (ai,bi) } should be converted to def
testTs[A](a:List[String],b:List[A]):List[(String,A)]={
val result = for{
ai <- a
bi <- b
} yield (ai,bi) } also instead of hover your mouse over variables you must press ctrl+q when your mouse is hover on that variable
eclipse have some problems in code
completion (when you use a variable
in next line and you want get a
property of this variable eclipse
show wrong code suggestions)
in IDEA ruining a scala application
is 5 sec slower than eclipse (there is some solution for bust IDEA run time but these have side effect have some problems)
in idea there is a well known problem with double click speed that show itself in many cases like opening a file or selecting an string in source... you can increase double click time out by creating (or editing) /home/.Xresources and add this line: *.multiClickTime: 400
Edit1: in summery i prefer to use IDEA rather than eclipse
My experiences clearly point to IntelliJ IDEA:
About six months ago, when I started a serious Scala (multi module) project, I had to abandon Eclipse as my favorite Java IDE and switched to IntelliJ (9.0.x). Eclipse Scala IDE was way to buggy and often stopped responding at some point, even for the most simple projects. For CI (Hudson) and command line build, I depend on Maven (with Scala plugin). The Maven dependencies (incl. Scala libs) are picked up nicely by IntelliJ.
A few days back I updated to IDEA X (CE) with the current plugin (nightly build) and work became even smoother. Although fsc still terminates after a while when inactive.
From what I see, I'd like to add, that there seems to be way more activity on the IntelliJ side to respond to bugs and improve the plugin continuously. Correct me when I'm wrong, but Eclipse Scala IDE development seems almost stalled. Still no 'official' Helios release!
NB: Just to provide some context (not bragging, really): The aforementioned project consists of about 25 Scala modules (POMs), 5 Java modules, 325 Scala files with a total of about 360 Scala classes, case classes and traits (> 19 kLOC, including comments). My platform is OS X 10.6, Scala 2.8.1, Java 1.6.
UPDATE: After having the need for pretty extensive refactorings (mainly move class, rename package), I discovered that the recent IDEA 10.0.1 plugin 0.4.413 (and probably older versions, too) has quite some problems getting stuff right. I don't want to explain the specifics, but I (almost ever) ended up manually fixing unresolved references or otherwise messed-up code. You can have a look at http://youtrack.jetbrains.net to get an idea.
For everyone who is really considering doing some serious development with Scala, I strongly recommend to evaluate the IDEs in question beyond the basics. When you are into an agile approach, which in my option requires a painless refactoring support without surprises (especially in multi-module projects), things are pretty tight at the moment.
It would be pretty neat, if someone came up with a IDE independent specification-like list of refactorings (and desired outcomes), which could be used to verify an IDE's refactoring support.
A non-answer: None.
Based on what a perceived majority says, IDEA is probably the best Scala IDE today. And it (read: the Scala plugin) sucks. It does not handle fsc well, type inference is a mess, many errors are not shown, a number of non-errors are marked as errors, it is slow (when inspections are turned on), the test runner silently swallows aborting (!= failing) tests, ...
So I switched to a simple text editor with syntax highlighting on one and a maximized shell with SBT (simple build tool) on the other screen. Awesome! SBT is responsive (you can let file changes trigger recompilation of affected code and even reruns of tests), manages dependencies very smoothly and has helpful output (esp for tests; using ScalaTest). SBT increased my productivity compared to IDEA a lot.
You lose code completion, of course, altough geany offers me identified symbols. But as long as IDEs don't get type inference to work properly code completion does not help, anyway.
Some people care a lot about code refactoring. Well, the IDEs apparently don't make a good job there either. Even if they would, I'd rather only open them for this particular task than use them all the time.
I think that the best option so far is the ScalaIDE for Eclipse. You can go to the ScalaIDE Web Site and look around to see by yourself.
http://scala-ide.org/
Strong points I see about it are:
documentation,
tutorials,
constant releases,
support from Typesafe.
Here below a summary of the main features:
Scala IDE provides support for development of Scala applications in the Eclipse platform. Its main target is the support for the Scala language and the integration with the Eclipse Java tools. It provides many of the features Eclipse users have come to expect including:
Support for mixed Scala/Java projects and any combination of Scala/Java project dependencies. Type driven operations are transparent across Scala and Java files and projects, allowing straightforward references from Scala to Java and vice versa.
A Scala editor with syntax highlighting, inferred type, hyperlinking to definitions, code completion, error and warning markers, indentation, brace matching.
Project and source navigation including Scala support in the Package explorer view with embedded outline, outline view, quick outline, open type, open type hierarchy.
Incremental compilation, application launching with integrated debugger, hyperlinking from stack traces to Scala source, interactive console.
Support for Eclipse plug-in and OSGi development including hyperlinking to Scala source from plugin.xml and manifest files.
UPDATE: the features and advantages are mentioned on this answer are for version 2.9 and 2.10 of Scala, because it has been already discontinued. see here:
"The 2.0.1 release is only available for Scala 2.9, if you would like to use the Scala IDE with Scala 2.8, please install the 2.0.0 release (support for Scala 2.8 has been discontinued after the 2.0.0 version)"
The officially endorsed and supported (by Typesafe) for Scala 2.9 is Eclipse. The current version is far superior to prior versions and includes a context-aware REPL, full-featured debugger, and even the ability to debug REPL statements. I think this question needs to be updated and the answers revisited.
I don't recommend the Scala IDE/Eclipse. It doesn't have a lot of the features that are even available for Eclipse with Java. And there are bugs.
I am using the latest NetBeans and haven't tried anything else. I've met at least 2 notable bugs in NetBeans while coding in Scala:
One: NB occasionally come unable to run a program, hanging on classpath scanning.
Solution: Create a new project, copy your code there and go on.
Comment: This bug is more than 10 years old.
Two: Sometimes NB can't see members of particular namespaces or classes and complains when you use them.
Solution: Just ignore and go on - compiler founds no errors and the program works.
I'd recommend IDEA's plugin for now.
The Scala plugin for NetBeans is quite nice too. It doesn't yet support NetBeans 6.9, the newest release, though, and you still need to download it manually instead of installing it directly from the plugin manager inside NetBeans.
However, it integrates better with Maven projects than IDEA's plugin does (this is true for NB and IDEA in general, in my opinion).
It partly depends on your style of working, as all the options have strengths and weaknesses.
If you need refactoring across mixed java/scala projects, then IntelliJ is your only option.
If you want to do any work on the compiler or a compiler plugin, then Eclipse has the advantage of being able to launch a runtime workspace with a custom compiler build, including breakpoints. It also improved massively for the 2.8 Scala release.
Netbeans is a fine choice to go with if you're already very familiar with that platform, the costs of learning a new environment may well outweigh any benefits, and all three solutions are improving rapidly.
I haven't tried netbeans scala plugin yet, but I find that Intellij IDEA plugin is at any way much better a scala ide than the Scala eclipse plugin, which is sooooo slow that drives me crazy.
Though swing applications don't work well with my tiling window manager.
try IDEAX the latest community edition of Intellij IDEA (version 10), it has improved scala plugin which has faster code compilation and exceution in addition to that it has
Maven3 and SBT support with which we can develop Lift applications.
IntelliJ IDEA community edition + Scala Plugin + SBT plugin
For recent versions (2021) the question which ide takes a big portion of the home page https://scala-lang.org/

What are the good Scala IDEs at the start of 2010?

I know this is an exact duplicate, but a year has gone by and Scala seems to be a fast moving thing, so I figure it might be acceptable to ask again:
What is the best IDE for Scala development right now?
I know the Eclipse plugin is a work in progress and undergoing a complete re-write for Scala 2.8 but I saw a colleague use a nightly-build recently and it was extremely poor.
I use IntelliJ IDEA (the Community Edition 9 is free) and the scala plugin for it is really good. Excellent syntax highlighting, code navigation etc. It's not as good as the Java support but then I wouldn't necessarily expect that. It's good enough that I feel I'm more productive than I would have been in Java!
It has Specs integration and console integration as well.
I tried both Eclipse, NetBeans and IntelliJ IDEA,
Eclipse is the worst in my opinion. It is slow, sometimes messes up the syntax highlighting, almost always messes up the autocompletion and the whole IDE gets unresponsive from time to time. I would not recommend it for any kind of use except for self torturing.
NetBeans works better than the Eclipse plugin. Better highlighting, much better autocompletion but it has been reporting errors on a fairly complex syntax all over the source. But when i hit run, the code compiles just well. Could not understand why. Another issue is that autocomplete can not suggest private members of classes when you are writing inside the body of that class. Poor!
IntelliJ IDEA works just fine. I recommend that if you are seriously leaning against Scala development.
I hope that the Eclipse plugin will be more mature in time but given that it had plenty of time to become mature, I'm not a big fan of the idea. Scala has a great potential, being a well thought, programmer friendly language and running on JVM (which means great performance and high availability) but the poor IDE support is the worst thing for such language. Writing PHP on a simple text editor is acceptable but Scala, with such complex syntax and requirement to use the bloated Java libraries, there is a need of assistance. Maybe the current Scala community with functinal and Java background can not understand this but you can not expect newcomers to easily adopt to such a language instantly.
Anyway, go for IntelliJ IDEA...
Your main options are a fully fledged IDE like IntelliJ IDEA, NetBeans or Eclipse, or a text editor with some Scala awareness like TextMate or Emacs.
Personally, I like IntelliJ the best. I've been using it for Java development for many years, especially due to its refactoring and code navigation power. The Scala plugin was quite rough to start with, but is improving constantly. It's open source, I've been contributing bug reports and a few bug fixes.
The IDE plugins have all been working hard to be ready for Scala 2.8. It's been a moving target during the last 6 months, especially given that binary compatibility was broken as new features were added. So you might update to a new build of the compiler and then wait for supporting libraries (e.g. specs, scalatest) to be updated and recompiled.
Now that the Scala 2.8 Beta is imminent these problems are less frequent.
IntelliJ implements its own parser and type inference, as it does for Java. This lets it be more tolerant of errors and to immediately understand your code as you are editing. The type inference is not complete yet. Eclipse delegates most of this work to scalac, which means it they should always agree, but the information is only regenerated when you save files and the compiler is re-run. I don't know how NetBeans works in this regard.
Right now, IntelliJ's IDEA. And one big difference from now to a year ago is that a free, open source version of IDEA is available.
Personally, I use IDEA CE 9.0.1, but leave compilation&testing to SBT, which I keep running on another window, with cc or ~test.
In the context of 2.8, I have used Eclipse 3.5.x with the nightly plug-in and IDEA Community Edition 9.0. IDEA has been clearly better for me, except for compilation times. But I use sbt in parallel and it takes care of that.
My main issues with the Eclipse plug-in are:
Inability to change my tab settings in Eclipse (though that seems to work for others)
Code compiles but some errors are still highlighted and I need to close and reopen the file
Auto-completion just returns a lot of choices
I did not have those issues in IDEA 9.0 build #IC-93.13 with the recent plug-in 0.3.385. Additionally IDEA shows me unused import statements.
All plug-ins seem to be evolving quite quickly and are actively developed and I suspect that what is true today may not be in one month. I hope that in a few months from now, we will just be able to use our favorite IDE and have good Scala support.
(note this is a repost of my recent answer to the original question)