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For past 4 years, I have been programming with Eclipse (for Java), and Visual Studio Express (for C#). The IDEs mentioned always seemed to provide every facility a programmer might ask for (related to programming, of course).
Lately I have been hearing about something called "build tools". I heard they're used almost in all kind of real world development. What are they exactly? What problems are they designed to solve? How come I never needed them in past four years? Are they kind of command-line stripped down IDEs?
What are build tools?
Build tools are programs that automate the creation of executable
applications from source code (e.g., .apk for an Android app). Building
incorporates compiling,linking and packaging the code into a usable or
executable form.
Basically build automation is the act of scripting or automating a
wide variety of tasks that software developers do in their day-to-day
activities like:
Downloading dependencies.
Compiling source code into binary code.
Packaging that binary code.
Running tests.
Deployment to production systems.
Why do we use build tools or build automation?
In small projects, developers will often manually invoke the build
process. This is not practical for larger projects, where it is very
hard to keep track of what needs to be built, in what sequence and
what dependencies there are in the building process. Using an
automation tool allows the build process to be more consistent.
Various build tools available(Naming only few):
For java - Ant,Maven,Gradle.
For .NET framework - NAnt
c# - MsBuild.
For further reading you can refer following links:
1.Build automation
2.List of build automation software
Thanks.
Build tools are tools to manage and organize your builds, and are very important in environments where there are many projects, especially if they are inter-connected. They serve to make sure that where various people are working on various projects, they don't break anything. And to make sure that when you make your changes, they don't break anything either.
The reason you have not heard of them before is that you have not been working in a commercial environment before. There is a whole lot of stuff that you have probably not encountered that you will within a commercial environments, especially if you work in software houses.
As others have said, you have been using them, however, you have not had to consider them, because you have probably been working in a different way to the usual commercial way of working.
Build tools are usually run on the command line, either inside an IDE or completely separate from it.
The idea is to separate the work of compiling and packaging your code from creation, debugging, etc.
A build tool can be run on the command or inside an IDE, both triggered by you. They can also be used by continuous integration tools after checking your code out of a repository and onto a clean build machine.
make was an early command tool used in *nix environments for building C/C++.
As a Java developer, the most popular build tools are Ant and Maven. Both can be run in IDEs like IntelliJ or Eclipse or NetBeans. They can also be used by continuous integration tools like Cruise Control or Hudson.
Build tools are generally to transform source code into binaries - it organize source code, set compile flags, manage dependencies... some of them also integrate with running unit test, doing static analysis, a generating documentation.
Eclipse or Visual Studio are also build systems (but more of an IDE), and for visual studio it is the underlying msbuild to parse visual studio project files under the hood.
The origin of all build systems seems like the famous 'make'.
There are build systems for different languages:
C++: make, cmake, premake
Java: ant+ivy, maven, gradle
C#: msbuild
Usually, build systems either using a propriety domain specific language (make, cmake), or xml (ant, maven, msbuild) to specify a build. The current trend is using a real scripting language to write build script, like lua for premake, and groovy for gradle, the advantage of using a scripting is it is much more flexible, and also allows you the to come up with a set of standard APIs(as build DSL).
These are different types of processes by which you can get your builds done.
1. Continuous Integration build: In this mainly developers check-in their code and right after their check-in a build initiates for building of the recent changes so we should know whether the changes done by the developer has worked or not right after the check-in is done. This is preferred for smaller projects or components of the projects. In case where multiple teams are associated with the project or there are a large no. of developers working on the same project this scenario becomes difficult to handle as if there are 'n' no. of check-in’s and the build fails at certain points it becomes highly difficult to trace whether all the breakage has occurred because of one issue or with multiple issues so if the older issues are not addressed properly than it becomes very difficult to trace down the later defects that occurred after that change. The main benefit of these builds is that we get to know whether a particular check-in is successful or not.
2. Gated check-in builds: In this type of check in a build is initiated right after the check in is done keeping the changes in a shelve sets. In this case if the build succeeds than the shelve-set check-in gets committed otherwise it will not be committed to the Team Foundation Server. This gives a slightly better picture from the continuous integration build as only the successful check-in's are allowed to get committed.
3. Nightly builds: This is also referred as Scheduled builds. In this case we schedule the builds to run for a specific time in order to build the changes. All the previous uncommitted changes from the last build are built during this build process. This is practiced when we want to check in multiple times but do not want a build every time we check in our code so we can have a fixed time or period in which we can initiate the build for building of the checked-in code.
The more details about these builds can be found at the below location.
Gated-check in Builds
Continuous Integration Builds
Nightly Builds
Build Process is a Process of compiling your source code for any errors using some build tools and creating builds(which are executable versions of the project). We(mainly developers) do some modifications in the source code and check-in that code for the build process to happen. After the build process it gives two results :
1. Either build PASSES and you get an executable version of your project(Build is ready).
2. It fails and you get certain errors and build is not created.
There are different types of build process like :
1. Nightly Build
2. gated Build
3. Continuous integration build etc.
Build tools help and automates the process of creating builds.
*So in Short Build is a Version of Software in pre-release format used by the Developer or Development team to gain confidence for the final result of their Product by continuously monitoring their Product and solving any issues early during the development process.*
You have been using them - IDE is a build tool. For the command line you can use things like make.
People use command line tools for things like a nightly build - so in the morning with a hangover the programmer has realised that the code that he has been fiddling with with the latest builds of the libraries does not work!
"...it is very hard to keep track of what needs to be built" - Build tools does not help with that all. You need to know what you want to build. (Quoted from Ritesh Gun's answer)
"I heard they're used almost in all kind of real-world development" - For some reason, software developers like to work in large companies. They seem to have more unclear work directives for every individual working there.
"How come I never needed them in past four years". Probably because you are a skilled programmer.
Pseudo, meta. I think build tools do not provide any really real benefit at all. It is just there to add a sense of security arising from bad company practices, lack of direction - bad software architectural leadership leading to bad actual knowledge of the project. You should never have to use build tools(for testing) in your project. To do random testing with a lack of knowledge of the software project does not give any sort of help at all.
You should never ever add something to a project without knowing it's purpose, and how it will work with the other components. Components can be functional separate, but not work together. (This is the responsibility of the software architect I assume).
What if 4-5 components are added into the project. You add a 6th component. Together with the first added component, it might screw up everything. No automatic would help to detect that.
There is no shortcut other than to think think think.
Then there is the auto download from repositories. Why would you ever want to do that? You need to know what you download, what you add to the project. How do you detect changes in versions of the repositories? You need to know. You can't "auto" anything.
What if we were to test bicycles and baby transports blindfolded with a stick and just randomly hit around with it. That seems to be the idea of build tool testing.
I'm sorry there are no shortcut
https://en.wikipedia.org/wiki/Scientific_method
and
https://en.wikipedia.org/wiki/Analysis
How would you implement a Plugin-system for your Java application?
Is it possible to have an easy to use (for the developer) system which achieves the following:
Users put their plugins into a subdirectory of the app
The Plugin can provide a configuration screen
If you use a framework, is the license compatible with commercial developement?
First you need an interface that all plugins need to implement, e.g.
public interface Plugin {
public void load(PluginConfiguration pluginConfiguration);
public void run();
public void unload();
public JComponent getConfigurationPage();
}
Plugin authors should then bundle their plugins into JAR files. Your applications opens the JAR file and could then use an attribute from JAR manifest or the list of all files in the JAR file to find the class that implements your Plugin interface. Instantiate that class, the plugin is ready to go.
Of course you may also want to implement some kind of sandboxing so that the plugin is restricted in what it can and can not do. I have created a small test application (and blogged about it) that consists of two plugins, one of which is denied access to local resources.
Use OSGi.
It is the foundation of the Eclipse plug-in system. Equinox is Eclipse's implementation (licensed EPL) and Felix is the Apache Project's implementation (licensed Apache Public License).
Eclipse provides a concrete example that OSGi can cover the points you mentioned (or you could just build your application on top of Eclipse RCP if you want a full Eclipse/SWT/JFace stack).
Since 1.6, there's been java.util.ServiceLoader which can be used if you want to code your own simple system.
But if you want anything more than basic features, use one of the existing frameworks.
Use PF4J.
It has support for Web, Spring and Wicket.
Easy to use and build the applications
There is also JPF (Java Plugin Framework).
I worked on OSGi for a week--an intense, nothing but OSGi week. At the end it was like a bad dream but I learned a lot.
I was able to get OSGi working (not easy, all examples are out of date, everything on the net is at least three years old if not five), but I had serious trouble getting it integrated into an existing project because of issues with the jar manifests.
In short, there are only a few obscure tools used for building manifests and they are not well documented (BND Tools is hardly obscure, but it is designed for a certain process in Eclipse). Also, most of the OSGi information available is not targeted towards application developers who have an existing desktop application.
This makes a lot of the context for the information foggy or inappropriate. Neil Bartlett's blog posts were the biggest help, but even those failed to get a working system (I grabbed some code from the Felix tutorial and pieced it together to get the embedded framework rolling). I found his book draft that he posted for free years ago, which is excellent, but the examples in Eclipse do not work because of changes in Eclipse OSGi support.
I think that recommending OSGi for solving the above stated problem is extremely poor advice. OSGi is "the right choice" but for a scenario as the one above, I think either JPF or some homegrown minimalistic framework is sufficient.
Years ago I started a project like that and I hope soon will be ready.I got inspired by projects like NetBeans and Eclipse but meanwhile it changed to something a little bit different. OSGi looks like a good choice now, but I didn't had a chance to compare it with my project.It is similar with JPF mentioned above, but in the same time different in many ways.
The basic idea which motivated me is to be as easy as possible to build Java application, with no separation between web applications, desktop applications or applet/JWS applications(of course this doesn't cover the UI - yet) as a core functionality.
I built the project with a few goals in my mind :
it doesn't matter if you build a web application or a desktop application you should start the application in the same way, a plain main method, No fancy web.xml declaration(not that I'm against having a standard web descriptor, but it doesn't go well with a plug-in system, where you add "servlets" - I call them RequestHandler(s) - dynamic at your will).
easy to plug in "extensions" around an "extension point" - something from Eclipse but a different approach.
self-deployable, since all the plugins are registered(XML files) the application must be self-deployable independent of the build system - of course there is an Ant task and a Maven MOJO which are the links with the ourside world, but in the end it calls the application and instruct it to self-deploy itself at a specific location.
borrowed from Maven, it can download code from repositories(including Maven 1 & 2 repositories) so your application can be deployed as a single small jar as long as you have access to the repositories(useful sometime, and basically this provides support for auto-updates - don't you love the idea to be notified by your web application that there is a newer version, it was downloaded and it just needs your permission to install it? I know I love that).
basic application monitoring about system health, email notifications in case of failures
How would you implement a Plugin-system for your Java application?
Is it possible to have an easy to use (for the developer) system which achieves the following:
Users put their plugins into a subdirectory of the app
The Plugin can provide a configuration screen
If you use a framework, is the license compatible with commercial developement?
First you need an interface that all plugins need to implement, e.g.
public interface Plugin {
public void load(PluginConfiguration pluginConfiguration);
public void run();
public void unload();
public JComponent getConfigurationPage();
}
Plugin authors should then bundle their plugins into JAR files. Your applications opens the JAR file and could then use an attribute from JAR manifest or the list of all files in the JAR file to find the class that implements your Plugin interface. Instantiate that class, the plugin is ready to go.
Of course you may also want to implement some kind of sandboxing so that the plugin is restricted in what it can and can not do. I have created a small test application (and blogged about it) that consists of two plugins, one of which is denied access to local resources.
Use OSGi.
It is the foundation of the Eclipse plug-in system. Equinox is Eclipse's implementation (licensed EPL) and Felix is the Apache Project's implementation (licensed Apache Public License).
Eclipse provides a concrete example that OSGi can cover the points you mentioned (or you could just build your application on top of Eclipse RCP if you want a full Eclipse/SWT/JFace stack).
Since 1.6, there's been java.util.ServiceLoader which can be used if you want to code your own simple system.
But if you want anything more than basic features, use one of the existing frameworks.
Use PF4J.
It has support for Web, Spring and Wicket.
Easy to use and build the applications
There is also JPF (Java Plugin Framework).
I worked on OSGi for a week--an intense, nothing but OSGi week. At the end it was like a bad dream but I learned a lot.
I was able to get OSGi working (not easy, all examples are out of date, everything on the net is at least three years old if not five), but I had serious trouble getting it integrated into an existing project because of issues with the jar manifests.
In short, there are only a few obscure tools used for building manifests and they are not well documented (BND Tools is hardly obscure, but it is designed for a certain process in Eclipse). Also, most of the OSGi information available is not targeted towards application developers who have an existing desktop application.
This makes a lot of the context for the information foggy or inappropriate. Neil Bartlett's blog posts were the biggest help, but even those failed to get a working system (I grabbed some code from the Felix tutorial and pieced it together to get the embedded framework rolling). I found his book draft that he posted for free years ago, which is excellent, but the examples in Eclipse do not work because of changes in Eclipse OSGi support.
I think that recommending OSGi for solving the above stated problem is extremely poor advice. OSGi is "the right choice" but for a scenario as the one above, I think either JPF or some homegrown minimalistic framework is sufficient.
Years ago I started a project like that and I hope soon will be ready.I got inspired by projects like NetBeans and Eclipse but meanwhile it changed to something a little bit different. OSGi looks like a good choice now, but I didn't had a chance to compare it with my project.It is similar with JPF mentioned above, but in the same time different in many ways.
The basic idea which motivated me is to be as easy as possible to build Java application, with no separation between web applications, desktop applications or applet/JWS applications(of course this doesn't cover the UI - yet) as a core functionality.
I built the project with a few goals in my mind :
it doesn't matter if you build a web application or a desktop application you should start the application in the same way, a plain main method, No fancy web.xml declaration(not that I'm against having a standard web descriptor, but it doesn't go well with a plug-in system, where you add "servlets" - I call them RequestHandler(s) - dynamic at your will).
easy to plug in "extensions" around an "extension point" - something from Eclipse but a different approach.
self-deployable, since all the plugins are registered(XML files) the application must be self-deployable independent of the build system - of course there is an Ant task and a Maven MOJO which are the links with the ourside world, but in the end it calls the application and instruct it to self-deploy itself at a specific location.
borrowed from Maven, it can download code from repositories(including Maven 1 & 2 repositories) so your application can be deployed as a single small jar as long as you have access to the repositories(useful sometime, and basically this provides support for auto-updates - don't you love the idea to be notified by your web application that there is a newer version, it was downloaded and it just needs your permission to install it? I know I love that).
basic application monitoring about system health, email notifications in case of failures
What type of developer are each of these IDEs aimed at? Is one IDE a superset/subset of the other? What can I do using one and not the other?
I'm looking to do mostly desktop based (Windows) work for now so I believe I am correct in ignoring the Java EE download and focusing on these two.
The comparison of features page isn't helpful as I'm still new to Eclipse and Java. For example "Code Recommenders Developer Tools" means nothing to me yet.
Eclipse standard has been downloaded 1.7 million times and is 246MB (as at 7-Sep-13). While Eclipse IDE for Java developers has been downloaded 430,000 times and is 151MB.
So I'm guessing Eclipse Standard is the way to go, but why do they offer the second option?
All the other answers are more or less true, but miss the point (in my opinion), The download page states it clearly:
Eclipse Standard ...
The Eclipse Platform, and all the tools needed to develop and debug it
versus
Eclipse IDE for Java Developers ...
The essential tools for any Java developer, including a Java IDE, a CVS client, Git client, XML Editor, Mylyn, Maven integration...
So if your focus is to develop for Eclipse itself, the Eclipse Standard includes all what you need (including the sources of all features and plugins).
If your focus is Java development (not Eclipse plugins), you should start with the Eclipse IDE for Java Developers.
If your focus is Java EE development, it is simpler to start with Eclipse IDE for Java EE Developers and so forth ...
The comparison page could certainly use some links, nevertheless a quick web search will tell you all about those plugin.
For your needs, you might look into the "for Java Developers" package, as it contains WindowBuilder, which let's you define GUIs visually in several frameworks.
(Code Recommenders is also nice, but I've personally found it a bit hit-or-miss)
However, you're fine installing any of the packages either way, since you can always install the plugins you need later on. My recommendation is to simply read about those plugins and make an informed decision on what you should install.
If you're doing GUI work then you might choose the Java Developers package as it comes with WindowBuilder.
Other similar questions are:
https://stackoverflow.com/questions/7835305/what-are-my-options-for-developing-a-gui-in-java-in-eclipse
Best GUI designer for eclipse?
Create GUI using Eclipse (Java)
The difference between the eclipse downloads are just the pre-installed plug-ins.
I'd go with standard and install the plug-ims i want, but take what fits you.
what's the point of using ant, maven, and buildr? won't the using build in eclipse or netbeans work fine? i'm just curious what the purpose and benefit of extended build tools are.
Dependency Management: The build tools follow a component model that provides hints on where to look for dependencies. In Eclipse / Netbeans, you have to depend on a JAR and you don't really know if this JAR has been updated or not. With these build tools, they 'know' updates in dependencies (generally because of a good integration with your source control repository), recalculate transitive dependencies and ensure that everything is always built with the latest versions.
Access Control: Java, apart from class level access control, has no higher abstraction. With these build tools you can specify exactly which projects you want to depend on you and control visibility and access at a higher level of granularity.
Custom Control: The Eclipse / Netbeans build always builds JAR files. With custom build mechanisms, you could build your own custom (company-internal) archive with extra metadata information, if you so wish.
Plugins: There are a variety of plugins that come with build tools which can do various things during build. From something basic like generating Javadocs to something more non-trivial like running tests and getting code coverage, static analysis, generation of reports, etc.
Transport: Some build systems also manage transport of archives - from a development system to a deployment or production system. So, you can configure transport routes, schedules and such.
Take a look at some continuous integration servers like CruiseControl or Hudson. Also, the features page of Maven provides some insight into what you want to know.
On top of all the other answers. The primary reason I keep my projects buildable without being forced to use NetBeans or Eclipse is that it makes it so much easier to setup automated (and continuous) builds.
It would be rather complicated (in comparison) to set up a server that somehow starts eclipse, updates the source from the repository, build it all, sends a mail with the result and copies the output to somewhere on a disk where the last 50 builds are stored.
If you are a single developer or a very small group, it can seem that a build system is just an overhead. As the number of developers increases though it quickly becomes difficult to track all changes and ensure developers are keeping in sync. A build system reduces the rate of increase of those overheads as your team grows. Consider the issues of building all the code in Eclipse once you have 100+ developers working on the project.
One compelling reason to have a separate build system is to ensure that what has been delivered to your customers is compiled from a specific version of the code checked into your SCM. This eliminates a whole class of "works on my box" issues and in my opinion this benefit is worth the effort on its own in reduced support time. Isolated builds (say on a CI server) also highlight issues in development, e.g. where partial or breaking changes have been committed, so you have a chance to catch issues early.
A build in an IDE builds whatever happens to be on the box, whereas a standalone build system will produce a reproducible build directly from the SCM. Of course this could be done within an IDE, but AFAIK only by invoking something like Ant or Maven to handle all the build steps.
Then of course there are also the direct benefits of build systems. A modular build system reduces copy-paste issues and handles dependency resolution and other build related issues. This should allow developers to focus on delivering code. Of course every new tool introduces its own issues and the learning curve involved can make it seem that a build system is a needless overhead (just Google I hate Maven to get some idea).
The problem with building from the IDE, is that there are tons of settings affecting the build. When you use a build tool all the settings a condensed in a more or less readable form into a small set of scripts or configuration files. This allows in the ideal case anybody to execute a build with hardly any manual setup.
Without the build tool it might become next to impossible to even compile your code in let's say a year, because you'll have to reverse engineer all the settings
Different features. For example Maven can scan your dependencies and go download them, and their dependencies so you don't have to. For even a medium sized project there may be a very large number of dependencies. I don't think Eclipse can do that.
#anonymous,
Why do you I assume that me, a member
of your team, is using an IDE all the
time? I might want to build the code
on a headless build server, is that
ok?
Would you also deny me the right of
using a continuous integration
engine?
May I fetch dependencies from a central repository please? How can I do that?
Would you tie me to a specific IDE? I can't run Eclipse easily on my very old laptop, but I'll buy a new one.
Maybe I should also uninstall subversion and use patches or just zip folders on a sftp/ftp/Samba share.
The build tools allow you to do a build automatically, without human invention, which is essential if you have a code base being able to build many applications (like we do).
We want to be certain that each and everyone of our applications can build correctly after any code base changes. The best way to check that is to let a computer do it automatically using a Continouos integration tool. We just check in code, and the CI server picks up there is a change and rebuilds all modules influenced by that change. If anything breaks the responsible person is mailed directly.
It is extremely handy being able to automate things.
To expand on Jens Schauder's answer, a lot of those build options end up in some sort of .project file. One of the evils of Eclipse is that they store absolute path names in all of it's project files, so you can't copy a project file from one machine to another, which might have its workspace in a different directory.
The strongest reason for me, is automated builds.
IDEs just work on a higher abstraction layer.
NetBeans nativly uses Ant as its underlying build tool and recently can directly open maven projects in NetBeans. Hence, your typical NetBeans project can be compiled with ant and your maven project already is a NetBeans project.
As with every GUI vs CLI discussion, IDEs seem easier for beginners but once you get the idea it becomes cumbersome to do complex things.
Changing the configuration with an IDE means clicking somewhere which is easy for basic things but for complex stuff you need to find the right place to click. Furthermore IDEs seem to hide the importent information. Clicking a button to add a library is easy but you may still not know where the library is, etc.
In contrast, using a CLI isn't easy to start with but becomes quickly easy. It allows to do complex things more easily.
Using Ant or Maven means that every one can choose his/her own IDE to work one the code. Telling someone to install IDE X to compile it is much more overhead than telling "run <build command> in your shell". And of course your can't explain the former to an external tool.
To sum up, the IDE uses a build tool itself. In case of NetBeans Ant (or Maven) is used so you can get all the advantages and disadvantages of those. Eclipse uses its own thing (as far as I know) but also can integrate ant scripts.
As for the build tools themselves Maven is significantly different from Ant. It can download specified dependencies up to the point of downloading a web server to run your project.
In all projects, developers will often manually invoke the Build process.but it is not Suitable for large Projects, Where it is very difficult to keep track of what needs to be built, in what sequence and what dependencies there are in the building process.Hence we Use Build Tools for Our Projects.
Build Tools Done varieties of the task in the Application which will do by the Developer in their daily life.
They are
1.Downloading dependencies.
2.Compiling source code into binary code.
3.Packaging that binary code.
4.Running tests.
5.Deployment to production systems.