Can PMD, FindBugs, and Checkstyle be used together for a Java development project? Does it lead to wide overlapping of functions? Or else, can the same results be achieved using Sonar instead?
Yes, you can use PMD, FindBugs and Checkstyle together for a Java development project. There will be overlap, so you will have to select the rules that you activate accordingly. You could start with the default rulesets and then see which findings are being reported by more than one tool.
Using SonarQube (formerly Sonar) will also work. SonarQube uses all three tools (and more) under the hood. Using the SonarQube plugin for your IDE, you can also see the SonarQube findings in your code directly. However, you may still run into some overlap depending on your configuration. Chances are smaller though. SonarQube has recently begun providing their own detectors for much of the Checkstyle, PMD, and FindBugs functionality. Those SonarQube provided detectors have little to no overlap among themselves. Also, the "Sonar Way" default ruleset is configured so that there is no overlap.
However, if you want to utilize static code analysis professionally, you must be prepared to spend a significant amount of time configuring and fine-tuning the toolchain. After a while, the question of overlap becomes less present, and you will develop opinions on which detector implementation is best for your situation.
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I'm looking for a build tool (such as ant, maven, make, etc.) that uses JSON-based configuration files?
Does such a tool exist?
Nokia/Qt just announced their "QBS" build system, which is JSON-based, and is actually a build engine intended for easy adoption by IDEs (a principal reason for adopting JSON).
Introducing qbs
Rather than a "pre-make" generator of Makefiles/vcprojs/etc. (like CMake and QMake, etc.), qbs is intended to actually be the build engine.
Google turned up Gaudi though it is still in the early phases.
I think what you're really looking for is a build tool that doesn't force you to configure everything in XML?
In that case your best bet is Gradle. It doesn't have the same sort of adoption as ANT or Maven, but does have the advantage of learning lessons from both.
I would advise you to beware of straying from standard build tooling... It makes life tougher for others attempting to build your code. This is something Gradle solved by providing a build wrapper.
Disclaimer: I am relatively unfamiliar with the flash build processes, so some/all of this may be misinformed nonsense. Please feel free to suggest alternative approaches.
We're currently developing a flex web app and our build situation is far from ideal. At present we're (as in individual developers) just building using FlashBuilder and deploying manually. The programmers are currently screaming bloody murder for two reasons, though:
The lack of CI is like going back to the stone age
We don't much care for FlashBuilder
(Note: We're only using FlashBuilder because it was the easiest way to set up a flex project in conjunction with Away3d and get it building / rendering correctly -- it's a stopgap solution).
As a predominately .NET development shop, we're used to doing continuous integration as well as continuous deployment. Ideally, we'd like to get something comparable to this for our flash projects without tying ourselves to a particular IDE.
Requirements:
The build process must be:
.. runnable via the commandline
.. runnable on both developer and CI build machines (and certainly not requiring an IDE!)
.. preferably as IDE-independent as possible (pragmatism will kick in though; if this causes a lot of friction we'll just pick one).
.. able to run on Windows (we develop using Windows)
We don't mind a touch of duplication or a few manual steps (e.g. tarting up the build scripts if we add a new project via an IDE, or generating one configuration from another if tools exist), but the less duplication / maintenance required the better.
I've read quite a few articles / blog posts and watched some short screencasts, but most of them are very thin on the ground on how the build system sits alongside IDEs. Most articles/screencasts have the same formula: How to create a "Hello World" build using a single file & text editors (no IDE).
I've not seen the topic of multiple libraries/projects etc. being broached, either.
After reading around the issue for a while, I'm considering investigating the following options:
Project Sprouts
Flexmojos
Maven Flex Plugin
buildr as3
Does anyone have any experience of the above solutions (or others I'm unaware of) and, if so, what do you make of them? Any help / pointers appreciated.
I recently started building with Gradle and the GradleFx plugin and I immediately fell in love with its power and ease of use.
Gradle is ANT + Maven + Ivy evolved and is primarily used from the command-line. You can:
write scripts in Groovy (a powerful Ruby-like language that runs in the Java Virtual Machine)
access all existing Maven and Ivy repositories as well as your own repos
use existing ANT tasks
integrate with CI (in Jenkins you just tick a checkbox to activate Gradle support)
although it has originally grown from the Java/Groovy community, it is in fact language agnostic. You add language-specific plugins for added functionality. GradleFx is such a plugin that provides you with additional ActionScript/Flex building tasks.
do easy multi-project builds. e.g. you can compile, unit test, package and deploy both your .NET service layer and your Flex client application with just one command.
use convention over configuration: if you stick to the conventions, your build scripts will be extremely terse
generate all kinds of reports: unit testing, checkstyles, codenarc, ...
generate Eclipse, IDEA or other IDE projects
all the things I haven't discovered yet
And best of all: it's very easy to learn. I had no knowledge of Maven before I started with Gradle and could get a multi-project build with some customizations working quite quickly.
Edit (comparison to Buildr AS3 and Maven)
I can compare this only to one of the projects you mentioned: Buildr AS3. It seems to start from a philosophy that is similar to Gradle's. But I've tried to use it about half a year ago and couldn't even get a simple 'Hello World' app to work. I e-mailed the developer for help: no response.
Compared to GradleFx: I had a small forum discussion with the developer (on a rather philosophical topic, since I didn't really need any help because it just worked right away). He answered within minutes.
As for Maven: (for what it's worth) I've only glanced at some configurations and they seem overly complicated when I compare them to a Gradle script.
There is one thing Maven does that you can't do with GradleFx (yet). It can pull the right Flex SDK from a Maven repo and build against that. With GradleFx you have to have your SDK's available locally.
I'm quite familiar with using maven as the main build tool and the flexmojos plugin from Sonatype. My experience has been a bit of a roller coaster with flexmojos. Maven is completely solid, it works all the time without issue, the only issue is the flexmojos plugin which has fluctuated a lot between versions. If you choose to go this route make sure to grab the source for flexmojos so you can see what your configuration options are actually doing to the command line parameters etc. For Flex 3.x flexmojos 3.x up to around 3.9 is good and works fine with regard to the goal for generating the .project eclipse files, believe there's also a mojo (a maven plugin) for generating intelliJ IDEA project files as well as others. If you're using Flex 4 you can compile with the latest flexmojos 4.0RC2 but it appears to me that the goal for generating flex/flashbuilder project properties is now gone (I'm not sure if this is because it's been replaced by another plugin altogether or what the deal is). However building with maven and flexmojos does fulfill all of your goals above (we also use it for building our service layer, so in a single mvn clean install we get a jar packed in a war packed in an ear with everything configured and a swf, that part is really nice). Also you can do continuous integration using bamboo (or simply write your own script that is triggered from a cron job or in windows as a batch file executed with a scheduled task if you don't have a *nix server around). Let me know if you'd like any more details or if I missed something major.
Shaun
I have been using Hudson, now Jenkins, with Ant for Flex automated builds and FlexUnit testing. Jenkins has some really useful plugins for integration with eclipse (and hence, FDT or FlashBuilder), Jira, SVN, Git etc., and it's free. Also, you can integrate the Ant build into Maven scripts, so I've found this to be a good and flexible solution for all purposes I've come across so far.
The Flex SDK comes with Ant tasks, and writing even elaborate Ant build scripts is quite easy - in fact, I'd been using Ant locally before, and I could reuse my existing scripts with only a few added extra compiler options for FlexUnit tasks.
However, it took a while to set up the system correctly for unit testing, because I'm running a headless server on Linux, and that implicates a rather complicated environment for ActionScript tests, because they run only in Flash Player. This, of course, is true for all CI scenarios using FlexUnit, regardless of which server you use.
Here's what I've learned:
FlexUnit needs a standalone debugger version of Flash Player installed, but Adobe only distributes binaries for the standard version on Linux. Therefore, compiling from source was necessary, and since my server system is stripped down to the bare necessities, it took some effort to install all the correct dependencies and get them to work.
The Flash Player needs hardware to run correctly: It uses graphics, therefore it needs a graphics card, and sounds, therefore it needs a sound card. On my headless server, this meant I had to install a VNC host to get it to run at all, and I had to eliminate any tests using sounds (those will now only run on local machines). If anyone ever comes across a working sound card emulation for openSuSE that I could use with the VNC client - you'll be my hero forever!
If you've set asynchronous timeouts in your unit tests, and/or you need to use setTimeout() to send delayed procedure calls, make sure the intervals aren't too short - I've had problems with tests that ran fine on any local machine, but broke the build on the CI server, because the Flash Player is considerably slower on the VNC client than on an actual graphics card.
I've also found this last issue to be a healthy lesson: Criteria for unit tests should not be based on assumptions about the system's performance, or at least be tolerant enough to succeed even on a slow machine.
I need to define a runtime environment for my development. The first idea is of course not to reinvent the wheel. I downloaded macports, used easy_install, tried fink. I always had problems. Right now, for example, I am not able to compile scipy because the MacPorts installer wants to download and install gcc43, but this does not compile on Snow Leopard. A bug is open for this issue, but I am basically tied to them for my runtime to be usable.
A technique I learned some time ago, was to write a makefile to download and build the runtime/libs with clearly specified versions of libraries and utilities. This predates the MacPorts/fink/apt approach, but you have much more control on it, although you have to do everything by hand. Of course, this can become a nightmare on its own if the runtime grows, but if you find a problem, you can use patch and fix the issue on the downloaded package, then build it.
I have multiple questions:
What is your technique to prepare a well-defined runtime/library collection for your development?
Does MacPorts/fink/whatever allows me the same flexibility of rehacking if something goes wrong ?
Considering my makefile solution, when my software is finally out for download, what are your suggestions about solving the potential troubles between my development environment and the actual platform on my user's machines ?
Edit: What I don't understand in particular is that other projects don't give me hints. For example, I just downloaded scipy, a complex library with lots of dependencies. Developers must have all the deps setup before working on it. Despite this, there's nothing in the svn that creates this environment.
Edit: Added a bounty to the question. I think this is an important issue and it deserves to get more answers. I will consider best those answers with real world examples with particular attention towards any arisen issues and their solution.
Additional questions to inspire for the Bounty:
Do you perform testing on your environment (to check proper installation, e.g. on an integration machine) ?
How do you include your environment at shipping time ? If it's C, do you statically link it, or ship the dynamic library, tinkering the LD_LIBRARY_PATH before running the executable? What about the same issue for python, perl, and other ?
Do you stick to the runtime, or update it as time passes? Do you download "trunk" packages of your dependency libraries or a fixed version?
How do you deal with situations like: library foo needs python 2.5, but you need to develop in python 2.4 because library bar does not work with python 2.5 ?
We use a CMake script that generates Makefiles that download (mainly through SVN)/configure/build all our dependencies. Why CMake? Multiplatform. This works quite well, and we support invocation of scons/autopain/cmake. As we build on several platforms (Windows, MacOSX, a bunch of Linux variants) we also support different compile flags etc based on the operating system. Typically a library has a default configuration, and if we encounter a system that needs special configuration the configuration is replaced with a specialized configuration. This works quite well. We did not really find any ready solution that would fit our purpose.
That being said, it is a PITA to get it up and running - there's a lot of knobs to turn when you need to support several operating systems. I don't think it will become a maintainance-nightmare as the dependencies are quite fixed (libraries are upgraded regularly, but we rarely introduce new one).
virtualenv is good, but it can't do magic - e.g. if you want use a library that just MUST have Python 2.4 and another one that absolutely NEEDS 2.5 instead, you're out of luck. Nor can virtualenv (or any other tool) help when there's a brand new release of an OS and half the tools &c just don't support it yet, as you mentioned for Snow Leopard: some problems are just impossible to solve (two libraries with absolutely conflicting needs within the same build), others just require patience (until all tools you need are ported to the new OS's release, you just need to stick with the previous OS release).
We use Incredibuild here to compile our code in a distributed fashion. I was wondering if there are any open source (or free) alternatives to use on a home network?
Failing that, are there any other simple solutions with good integration with Visual Studio out there?
EDIT: I should say that I am quite happy to get my hands dirty and manually configure everything on each machine should that be required.
I can't look past TeamCity as a CI environment - among other features it allows multiple build agents to be linked together in one build grid.
Oh and it also has excellent integration with VS and SubVersion. And it's free to use, up to a maximum of 20 build configurations and 2 build agents.
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I need some resources that talk about how to design your software to be extensible, i.e. so that other people can write add-ons/plug-ins that adds functionality to it.
What do you recommend? Any books out there that discuss the subject?
I would prefer something that's short and to the point; a bit of theory and a bunch of concrete examples.
I'm not targeting a specific language, I want to be able to understand the core idea so that I can implement it in any language.
And for the same reason, I prefer not to do it using a framework that someone else built (unless the framework is not very high-level, i.e. doesn't hide too much), at the moment I only want to educate myself on the subject and experiment with various ways to implement it. Plus, a framework usually assumes user's knowledge about the subject.
UPDATE
I'm not asking about OOP or allowing my classes to be inherited. I'm talking about designing an application that will be deployed on a system, such that it can be extended by third-party add-ons AFTER its been deployed.
For example, Notepad++ has a plug-in architecture where you can place a .dll file in the plugins folder, and it adds functionality to the application that wasn't there, such as color-picking, or snippet insertion, or many other things (a wide range of functionality).
IF we're talking .NET, try Scripting .NET applications with VBScript over on CodeProject. Lots of concrete examples there.
Below are sites implementing various application extension techniques
ClearScript - Makes V8, VBScript and JScript available to .NET apps
CS-Script - The C# Script Engine
Plugin Architecture using C#
Opinio plugin architecture
Notes on the Eclipse Plug-in Architecture
Plug-in Architecture Framework for Beginners
Gecko plugin architecture
Fungimol plugin architecture
OSGI is a good practical example of a technical framework allowing to do what you are after.
The theory is here.
The (free!) book is there.
Extensibility and the ability to write plugin must deal with service lifecycle
adding / removing service/plugin on the spot
managing dependencies between services
managing states of services (declared, installed, started, stopped,...)
What is OSGI for ?
One of the main functions of a module is as a unit of deployment… something that we can either build or download and install to extend the functionality of our application.
You will find a good introduction here, on the central notion of service (which is related to your question, and which explain some problems around services, key component for extensibility).
Extract:
Why are services then so important if so many applications can be built without them? Well, services are the best known way to decouple software components from each other.
One of the most important aspects of services is that they significantly minimize class loading problems because they work with instances of objects, not with class names. Instances that are created by the provider, not the consumer. The reduction of the complexity is quite surprising
Not only do services minimize configuration, they also significantly reduce the number of shared packages.
Implement SOLID principles in your application.
1. Single responsibility principle: A class should have only a single responsibility (i.e. only one potential change in the software's specification should be able to affect the specification of the class
2.Open/closed principle: Software entities … should be open for extension, but closed for modification
3. Liskov substitution principle: Objects in a program should be replaceable with instances of their subtypes without altering the correctness of that program
4. Interface segregation principle: Many client-specific interfaces are better than one general-purpose interface
5. Dependency inversion principle: One should Depend upon Abstractions. Do not depend upon concretions
Stackoverflow questions:
Example of Single Responsibility Principle
Is the Open/Closed Principle a good idea?
What is the Liskov Substitution Principle?
Interface Segregation Principle- Program to an interface
What is the Dependency Inversion Principle and why is it important?
You try to reach two competing goals:
The components of your software must expose a lot of themselves, so they can be reused
The components of your software must expose very little of themselves, so they can be reused
Explanation: To encourage code reuse, you should be able to extend existing classes and call their methods. This isn't possible when the methods are declared "private" and the classes are "final" (and can't be extended). So to meet this goal, everything should be public and accessible. No private data or methods.
When you release the second version of your software, you will find that many of the ideas of version 1 were plain wrong. You need to change many interfaces or your code, method names, delete methods, break the API. If you do this, many people will turn away. So in order to be able to evolve your software, the components must not expose anything that is not absolutely necessary - at the cost of code reuse.
Example: I wanted to observe the position of the cursor (caret) in an SWT StyledText. The caret is not meant to be extended. If you do it, you'll find that the code contains checks like "is this class in the package org.eclipse.swt" and a lot of methods are private and final and whatnot. I had to copy about 28 classes out of SWT into my project just to implement this feature because everything is locked down.
SWT is a nice framework to use and hell to extend.
Of course there is the famous Open Closed Principle - http://en.wikipedia.org/wiki/Open/closed_principle
Well it depends on the language.
In C/C++ I'm pretty sure there is a loadlibrary function that allows you to open a library at runtime and invoke it's exported functions. This is typically how it's done in C/C++.
In .NET, there is Reflection, which is offers similar (but more broad) to loadlibrary. There is also entire libraries built on Reflection like Managed Extension Framework, or Mono.Addins that does most of the heavy lifting for you already.
In Java, there is also Reflection. And there is the JPF (Java Plugin Framework) which is used in stuff like Eclipse IIRC.
Depending on what language you use I could recommend some tutorial/books. I hope this was helpful.
Plugin architecture is becoming very popular for its extensibility and thus flexibility.
For c++, Apache httpd server is actually plugin based, but a concept of module is used instead. Most of apache features are implemented as modules, like cache, rewrite, load balancing, and even threading model. It is a very modular software I ever saw.
And for java, Eclipse is definitely plugin based. The core of Eclipse is an OSGI module system which manage bundles, another concept for plugin. Bundle can provide extension points on which we can build modules with less efforts. The most intricate thing in OSGI is its dynamic characteristic, which means bundles can be installed or uninstalled at runtime. No stop-the-world syndrome any more!
Since I dont have enough rep points to leave a comment, I am posting this as an answer. SharpDevelop is an IDE for developing applications in C#/VB.NET/Boo. It has a pretty impressive architecture that allows itself to be extended in a number of ways - right from new menu items to development support for whole new languages.
It uses a bit of XML configuration to act as a glue layer between a core of the IDE and the plugin implementation. It handles locating, loading and versioning of plugins out of the box. Deploying new plugins is matter of simply copying in the new xml configuration file and the required assemblies (DLLs) and restarting the application. You can read more on this in the book "Dissecting a csharp application" by the original author(s) - Christian Holm, Mike Krüger, Bernhard Spuida of the application from here. The book doesnt seem to be available on that site, but i found a copy that might still be around here
Also found a related question here
Checkout "CAB" - Microsoft's Composition Application Building blocks Framework. I think they've got a "web version" of that too...
I have just started to develop a smart client application. These are two options I am considering.
Using Microsoft's System.AddIn namespace. Looks very promising, however it may be a little complex for our end solution.
Or the Smart Client - Composite UI Application Block from Microsoft
Recently, i have looked at taking components both the Composite UI Application Block and the System.AddIn namespace to build my own. Since source code is available for the CAB it is easy to extend. I think our end solution will be a light weight version of the CAB, definatly using the Unity Application Block
If you work with .Net, our research yielded two approaches: scripting and composition.
Scripting
You extend the functionality of what your classes can do by orchestrating them using scripts. That means exposing what is compiled in your favorite .Net language in a dynamic language.
Some options we found worth exploring:
IronPython
IronRuby
JavaScript: Jint, Jurassic and JavaScript .Net are good starting points.
Script.Net -> this one was the first one to call our attention.
Composition
If you start a project with .Net 4 or above, you must take a good look at the Managed Extensibility Framework (MEF). It allows you to extend the functionality of your apps in a plugin way.
The Managed Extensibility Framework (MEF) is a composition layer for
.NET that improves the flexibility, maintainability and testability of
large applications. MEF can be used for third-party plugin
extensibility, or it can bring the benefits of a loosely-coupled
plugin-like architecture to regular applications.
Managed Add-in Framework is also a good read.
MSDN: http://msdn.microsoft.com/en-us/library/dd460648.aspx
Codeplex: http://mef.codeplex.com/
Rather than re-inventing the wheel, use the frameworks in hand. Eclipse and Netbeans both support plugin based extensions. You have to work in Java though.