I am working on a project which uses Eclipse UML libraries, which are poorly supported on maven-central. The projects works well using the related jar libs in local. Now, we plan to deploy in using jenkins and docker, so now we want to make the maven build success. When ran locally with IntelliJ IDEA, the app works but when runnin mvn install, the jar libs are (obviously) not taken into account, and the build fails (package missing etc...).
I've investigated the maven-install-plugin for hours now, and I can not find a complete example and/or a MVP, with the syntax to use multiple jars in a libs folder during the maven build.
Can someone provide one or provide pointers to a clear and working example?
A possibly helpful "collection" of solutions, or pointers to solutions, for this kind of problem, including examples and discussion, can be found in this and that stackoverflow threads.
Though one wouldn't call that "clear". But it gives you a bundle of approaches to pick for your specific case.
Edit: Oh, and here, too.
Related
I am currently starting my adventure with Maven, and I actually don't understand the idea behind using it to automate compilation of my source code. For the time being I am working on small projects with up to 15-20 classes, and 1 main method in the "app" class. Could someone please give me the explanation with examples, when it's necesarry (or recommended) to use build automatation tool to compile the source code and how could I benefit from using it regarding source code compilation?
Thank you very much in advance!
I was looking for different answers and I have a lot of work to do but since I've seen this question, as a Maven fanboy, I couldn't resist anymore and this below is my answer.
First of all, I agree with JF Meier which answered before me, but I think the answer can be improved.
IMO you have to consider Maven not just as a build tool, but as a multi-purpose tool which can help you to do very different things. The best 3, for me are:
Compiler. Obviously. Maven allows you to easily compile giant projects with a lot of submodules, even if some of these modules are interdependent one with each other.
Dependency and repository manager. Maven allows you to automatically download third party software and bind this downlaod to the build. This is immediately understandable if you think to framework or api dependencies from big corps (Apache found., Spark, Spring, Hibernate and so on ...) but it's really powerful in every enterprise context.
Example: you have a Maven project (let's say project A) which manages requests coming from a webservice and provides responses. This Maven project relys on another Maven project (let's say project B) which actually generates webservice jar and uploads it to a company repository. Well, when you have to add a field or a method to the webservice you just have to implements new software in project B, upload it the repo and change the version in Maven poms in both project A and B. Voilà: now EVERY developer of the company just have to "mvn clean install" project A to have the new version.
Sources and code automatic generator. Since Maven 2.x are available a lot of plugins (from Apache found. and others) which allow you to generate code and sources (tipically xml files) starting from little to none implementations.
Example 1: CXF plugin is commonly used to generate java classes from xml or xsd files.
Example 2: JAXWS plugin is commonly used to generate wsdl from SOAP webservice implementations or implementation starting from wsdl file.
Do you feel the power now?
-Andrea
The question is not very specific, but I will try to answer.
Usually, you want your source code to end up in a jar or war, so that you can use it as a library or run it somewhere (e.g. on an application server).
Maven not only compiles the classes you have and creates the final artifact (jar, war), but also handles your dependencies, e.g. the libraries your project depends upon.
So I am new to the continuous integration world and of course, like everyone else, have been thrown into the task of setting it up and integrating it.
My company is .NET based and handles MVC applications, regular websites, form applications, as well as windows services. We have a ton of solutions in our repository and most of these solutions have trouble building in our CI that I am testing out (TeamCity). My local PC being the testing server.
Anyways, I have been reviewing a ton of documentation regarding TeamCity on their confluence pages but a lot of it is very technical and I'm getting tired of reading things more than once. So with that being said, there were some terms and concepts that I was a little confused on that I was hoping someone could explain pretty plainly maybe with an example.
Build Parameters -
I understand what parameters are and know what they are used for. Why would I use one in a build?
2.Snapshot dependencies -
What are these and When should I use them? I am having trouble visualizing this.
Artifact Dependencies -
I understand what artifacts are, I don't know why a project would need them to build however.
Any input would be greatly appreciated. Thanks guys.
I could give you some examples.
Build Parameters
It gives you a way to configure your build. For example, you may want to control your build version in Teamcity. You can use build parameters to specify major, minor version (with default value) for your build.
Personally, I try to avoid to use it as we should control configuration in source code or somewhere.
Snapshot dependencies
It is mostly used to build a chain of builds. For example, you have two builds. One is building source and other one is deploying to development environment. If you want to trigger deployment build after each source code build is successful, you need to add snapshot dependency to deployment build.
Artifact Dependencies
The same example as above, you want to deploy the artifact build in other build. In this situation, you need to use artifact dependency to copy the artifact into deployment build to upload somewhere etc.
Or sometimes you may have different projects, some projects are common libraries. If you don't have a artifact repository, you can use artifact dependency when those common libraries are required by other projects.
I am working on a project and using Maven to build it. The project is a quite big Java web application and it is supposed to work with both Mysql and Oracle databases.
The problem is that there are some specific annotations related to either of the two databases in the source code, plus some other differences, so that I am forced to manually comment/uncomment part of the code before building the application for one of the two databases.
Basically what I would like to achieve is to have my build script, maybe via a Maven profile, to automatically switch the source classes before building depending on the database I want my war to work against.
Putting it simply, the idea is to have MyClass.oracle and MyClass.mysql, and depending on my build profile I should move one of the two in the source dir, rename it MyClass and build. This should be done for some packages, classes, and also configuration files.
Is there any way I can achieve it via "pure" Maven? The only solution I came across till now is to use an antrun plugin and reference an Ant build.xml inside of it.
Thank you,
Mattia
A pure maven solution would be to develop your own maven plugin. Depending on your requirements this can be an overkill, however it is not hard at all, you can see how to achieve this here.
This is a limitation of Maven. One of Maven's purposes is to not have a build script. You should simply use the plugins as available, and setup your project the right way, and magically, everything will build!
There is one solution: Use Ant. Well, not to redo your whole project with Ant, but with the antrun plugin, you can run a few Ant tasks at various phases of your Maven build life cycle.
It's been a long, long time since I've used this, so I am not going to try to write a test pom.xml, but I don't remember it being very difficult to use.
Of course, the correct Maven solution is to divide your project up into "common core" code, and then a separate Oracle and MySql client that uses the "common core". By the way, I hope you're not patching source code. Instead, you're using a properties file to do this for you.
(first, I admit, I have no love for maven/m2eclipse, but it wouldn't be that bad if I could figure out how to overcome these issues)
I am using maven/m2eclipse. m2eclipse is the only good way I know of to suck in the maven jars. Some of these may not have solutions(but I am hoping to be surprised). Maybe solving #9 solves them all?
ISSUES
When I run "mvn clean package", I am dead in the water as far as running a unit test in eclipse while maven is building as I LOVE to multitask but maven prevents me here. How to get around this?
I move eclipse to point to eclipsegen/classes but then the unit tests are still using the classes in target/classes so it's not using my latest code that I just edited in eclipse and debugging is not lining up and it's stepping on blank lines that don't have code.
If I just slightly touch the pom.xml, bam, it builds when I don't really want it to and turning of automatic builds did not seem to help.
On top of #3, I get random pom builds downloading jars which just freezes eclipse from doing anything why the jars are being downloaded(I am a bit multitasker so this frustrates me to no end)
If I want to modify or do something really custom I need, the answer is usually create a java plugin but this then would require me to create another source control project with another automated build making sure the build tags all versions so we can reproduce issues with certain versions. (in ant, I just modify the xml to do custom stuff).
(I hear there is a bug open for 5 years on this one). global exclusions because people on our project keep breaking stuff when they include new things that depend on log4j and sucking that library in breaks us so we want to globally exclude it so people stop breaking the project when adding new things (IVY has global exclusions, why doesn't maven!!!!)
The xml code for generation from an xsd in maven is about 2-3 times the code of doing it in ant. Why is this? That really shouldn't be the case I think.
Running my unit test says xxxx-12.0.8-SNAPSHOT is missing but in my pom.xml it clearly says 12.0.9-SNAPSHOT not .8. ie. m2eclipse gets into some weird state and I get screwed wasting yet more time because someone selected maven
(I don't like IvyDE for the same reasons I don't like m2eclipse). In maven, is there any way like in Ivy to say on a build MOVE ALL jars into target/lib so that I can uninstall m2eclipse(if maven had this one feature, I think all my problems might go away)....That IS AN Ivy feature that rocks by the way!!!!
NOTE: I just realized that uninstalling m2eclipse and running "mvn eclipse:clean eclipse:eclipse" is not really an option since on this project I had to import 30 projects. I think on single projects, that is a great solution.
Is there no way like ant to log the command that was run for debugging purposes? ( in maven how to log the command that was run? )
I should really look into gradle(I hear it's best of maven and ant) as the theory of maven sounded great but you can tell there was a lot of controversy over it(which usually indicates a bad tool). Good tools that really help typically do have some controversy, but not as much as maven has had so it makes me think twice as I don't want to screw the guy who takes over my project(and I know ant will work). Many people I think don't even consider that. They think "I am fine, so why won't the next guy be fine".
Any ideas on how to fix the above issues?
About #9, if you have 2 alternatives :
Execute
mvn dependency:copy-dependencies
See http://maven.apache.org/plugins/maven-dependency-plugin/copy-dependencies-mojo.html for customization options. You'll have to set your Eclipse classpath manually to point to the newly copied jars.
Use JBoss Tools JDT Extensions to get the "Materialize Library" feature (see http://docs.jboss.org/tools/whatsnew/core/core-news-3.3.0.M4.html). You'll basically just have to right-click on the Maven Classpath library, select a destination folder, select (and rename) the jars you want, and you'll get a m2e-free project in Eclipse (still a valid Maven project in command line though).
You can install JBoss Tools JDT Extensions from http://download.jboss.org/jbosstools/updates/development/indigo/
Disclaimer: I like Maven and M2Eclipse, and I have not experienced any of the issues that you mention. In general, M2Eclipse does not get in the way much for the way I'm working.
One thing that might help is disabling the Maven Builder for the projects (right-click the project, select "Properties", then "Builders"). This will get rid of many of the issues you're complaining about.
One other thing that might help you (and comes close to #9 on your list: Uninstall M2Eclipse and use mvn eclipse:eclipse, which will generate Eclipse .project and .classpath files, which include all dependencies as Eclipse project dependencies. Whenever you add or change dependencies, you will have to run mvn eclipse:eclipse again. Give this a try...
Although it does sound like a faster PC would solve some of your issues I do agree that the m2eclipse plugin sucks (although it sucks a little less since eclipse indigo). Because of this I switched to using Intellij for a while but I switched back to eclipse after a month (for me, eclipse is still the best in spite of m2eclipse).
I use m2eclipse to be able to work in eclipse but nothing more. All my maven builds (package, install, whatever) I run with maven itself (command line) simply because there have been too many occasions where the result was different (working in one, not in the other and and maven was always correct).
So, sorry, no direct answers to your questions, just some tips:
1) do it outside eclipse
2) stick to maven standards (target/classes); that will make your life a lot easier
6) using dependency management in a parent pom might help a bit
8) if you get the same issue when running from command line then there is a problem in your pom (resolve using mvn dependency:tree), if not, see 1
9) maybe assembly is an option here but I would not recommend your approach
we have several projects in our company with many dependencies among them. we have gathered our projects (EJB,Web, Enterprise Application and ...), on a SVN server, now we have difficulties with our projects, because after checking out a project from SVN, we have to waste a long time to gather the required libraries and projects for the checked-out project to build.
i want to some help about that, how the maven technology could help us to easily gather the dependencies and build our projects automatically. we use myeclipse IDE.
moreover i need some help and resources, to learn how to achieve this goal.
any guide and help will be appreciated.
thanks in advance.
Depending on the amount of projects you have, and how complex their build is, switching to Maven can be a hell of a task. It might still be worthwhile, mainly because Maven forces you to do things "the Maven way"1, and that such a "Maven way" is becoming more standard with time: you might end up with a simplified/more standardized build procedure.
If your projects are currently built using ant, chances are that ivy can quite more easily solve your problem of offloading JARs from your VCS system, with a minimal impact to your current build configuration.
Otherwise, if you really think Maven is the right tool for you, I strongly suggest you to have a look at the official tutorial, the POM reference and start playing with simple, self generated projects to start having an idea about how to deal with Maven. Using the archetype:generate mechanism you have access to dozens (hundreds?) of sample projects (archetypes, in Maven jargon) that illustrate you how to deal with different kinds of projects, from simple JAR to more complex ones, maybe leveraging exotic frameworks or products. Have a look at the generated POM for such projects and try to understand how it works.
Integration with Eclipse is achieved via two different plugins. I'm not using Eclipse anymore since quite a while, but I think m2eclipse is still probably the best one to start with.
1- WARN: his is one of the things people coming to Maven heavily dislike more often than not