Setting up a standard directory layout using Maven - maven-2

I'm new to Maven and have skimmed over the documentation as I am following the Hibernate tutorial at http://docs.jboss.org/hibernate/stable/core/reference/en/html_single/#tutorial-firstapp-mvn.
I have installed Maven and successfully setup a web-app but this does not contain all of the standard directories mentioned in the tutorial. Am I going mad?
When building my Maven project I am using the maven-archetype-webapp. This gives me the arh-webapp\src\main\resources and arh-webapp\src\main\webapp directories but I'm missing quite a few directories mentioned on the link http://maven.apache.org/guides/introduction/introduction-to-the-standard-directory-layout.html.
Surely I don't have to manually add these? If not then the Hibernate documentation does not mention what archetype to use in order to achieve the directory structure used in their tutorial. Please can someone enlighten me.
What archetype do I need to use in order to have the above directory plus the src/main/java directory? If there is no such archetype then can easily append these using Maven? and how?

Surely you'll have to manually add these.
Just create those directories that according to the Maven convention are missing. Remember, a Maven Archetype is just a starting point to save you time configuring your workspace. After encountering many problems in some Archetypes myself I've been accustomed to just use a basic-web-app-archetype and then customize it myself, as a beginner with Maven you'll be better off doing that, and will learn a lot.
Regards.

Not all the directories mentioned are required for your standard web application. In fact, the reason behind the presence of the src/main/java, src/main/resources and the src/main/webapp directories is due to the archetype that you've used.
IMHO, the book titled "Better Builds with Maven" will serve you better; the Sonatype books on Maven might also help. The complete Maven documentation is also available as a PDF file, for future reference.
But just in case, you need some clarity on the terms used, here's some:
Archetype: A pattern for projects. Simple web applications (with no dependencies on other frameworks/libraries) have their own archetypes, so do applications using Spring, Hibernate, Seam, etc. Some archetypes will result in creation of different directories, as they are coded that way. You might be able to change the directory structures in most cases, although I cannot vouch for every archetype. For instance, it is quite possible to place your sources in 'src' instead of 'src/main/java', although this requires additional configuration in the POM.
Lifecycles, Phases and Goals: A Maven build lifecycle is a series of phases, with each phase executing a set of goals. Maven can be commanded to execute a build phase, which results in execution of all phases until and including the specified phase.
Maven plugins: Maven plugins contain one or more goals. Goals need not be bound to phases, but usually you would bind them to particular phases. Plugins are the basis for everything operational in Maven; you're using plugins even though you are just compiling the application (the Maven compiler plugin is a core plugin that is present in the Maven distribution).
I hope the above helps, but I would suggest that the reference books be followed.

Related

How do you perform a reactor build in Maven3 without a root project?

How does one perform an ad-hoc reactor build over multiple maven projects without a root project?
This used to be possible in maven2 by invoking the mvn command with the '-r' option which would search recursively from the working directory for projects and organize them in the reactor to build in the correct order even if the projects did not share a common parent pom.xml. Optionally one could specifically include or exclude certain projects using maven.reactor.includes and maven.reactor.excludes option.
I realize that the legacy reactor mode was removed from maven3 but I can't figure out how to achieve this functionality using the 'make-like' reactor mode.
The "Maven 2"-style reactor feature has been removed following this discussion on the mailing list. The relevant JIRA issue is MNG-4260.
As mentioned in the comments above, it's best to create a top-level pom with a <modules> section that lists the directories containing projects. (If you don't always build all of your projects at the same time, you can put separate modules sections in profiles).

need maven plugin configuration for building aggregate source jar

I've been fighting with this for a while and reading a lot of docs pages and other questions but still can't get it to work.
In my ORMLite project, I have a ormlite-core project which has core functionality and then a -jdbc and -android projects (with more planned). Each of these sub-projects include the core functionality but add per-architecture implementations. I want to release a single set of jars for both the -jdbc and -android versions -- i.e. I want to copy the -core javadocs and sources into the resulting jars.
For the javadocs, it was cake with the includeDependencySources config entry set to true. However, I've been fighting for a while now on how to get the source jars released by the -android package to include the -core sources. I've tried the maven-dependency-plugin to copy and unpack the dependency sources to target/sources but I see no easy way to get them to be included in the source jar -- with the appropriate paths. I've gone over the maven-source-plugin and maven-assembly-plugin docs but I'm still in the dark.
If someone has figured out the magic maven fu to get this done, can they please share the appropriate working pom.xml examples? Thanks much.
I've reviewed the following similar questions among others. I've also looked at the Sonatype Maven manual and read a bunch web pages posing similar questions.
Delivering a single jar with a Maven project
Maven - 'all' or 'parent' project for aggregation?
While not an answer to the question, a possible reason why a parameter like <includeDependencySources> is not present for maven source plugin is because, while javadocs can be generated from a jar containing classes, the sources cannot be. The plugin cannot assume that the sources of the dependencies are available to it since they do not get installed by default.
I guess the best answer to this question at this time is "you can't get there from here". This requires extensions to the maven-source-plugin.
I ended up determining that combining these sub-projects into the same jar was not a good idea and now I release 3 separate jars.

Maven multi-module project with many reports: looking for an example

Is there an open source project that can serve as a good example on how to use the maven site plugin to generate reports? I would prefer it to
consist of many modules, possibly hierarchically structured
use as many plugins as possible (surefire, jxr, pmd, findbugs, javadoc, checkstyle, you name it)
the reports should be aggregated: if some tests fail you want to have a single page that shows all modules with failing tests, not only a gazillion individual pages to check
include enterprisey stuff (WAR, EAR etc), but this is not so important.
The idea is to have something where you can gather ideas on how it is done and what is possible.
I gave up trying to aggregate reports of a complex multi-modules project with the maven-site-plugin. For this, I use Sonar, it's much more powerful (with features like evolution of metrics over time, aggregation, neat drill down, etc) and just works. Have a look at Nemo, the online demo instance and cry.
For an example see http://www.bartswennenhuis.nl/2013/12/maven-aggregate-reports-for-multi-module-projects/. Findbugs does not support aggregate reports.
I don't think there is such a project, if there is I want to know it as well. In order to find things in maven you have to know what you're looking for(which is not exactly the same with what you want to accomplish).
If its any help I'm building 13 module project with MAVEN, use cobertura maven plugin, surefire, javadoc, etc .. it works as charm, why are you asking this question, you want to determine the capabilities of maven or ?
this is actually a response to your question. please take a look at the Apache Directory project. it contains two big blocks: the directory server and the tooling support (Eclipse based).
you can find the SVN repository of the Apache Directory Studio (this is a complete directory tooling platform intended to be used with any LDAP server) here: http://svn.apache.org/repos/asf/directory/studio/trunk/
take a look at the POM file ( http://svn.apache.org/repos/asf/directory/studio/trunk/pom.xml ) of this multi module project. it consists out of lots of modules, uses most of the plug-ins you're using and it also aggregates some of the reports.this
You can use Violations Maven Plugin to aggregate Findbugs (and many other static code analysis) reports.
It needs to run after the analysis. It will parse their report-files and present them in one unified report. It can, optionally, fail the build depending on number of violations found.

What are some Maven project naming conventions for web application module?

When creating a project with the webapp archetype in Maven, they subtly advise not putting any Java source in the webapp project by not including the "src/main/java" folder.
What do you name your Maven projects?
project-webapp for the project that contains the JSP, CSS, Images, etc.
project for the project that contains domain specific entities
? for the project that contains the web application files like Servlets, Listeners, etc.
My first inclination would be to use "webapp" for the project containing the web application files (Servlets/Listeners), however the archetype uses "webapp" to convey the JSP/CSS/Images project and would cause confusion to other developers.
When creating a project with the webapp archetype in Maven, they subtly advise not putting any Java source in the webapp project by not including the "src/main/java" folder.
That's not really true. When you create a project with the maven-archetype-quickstart, you don't get a src/main/resources directory. Would that mean you should not put resources in this project? No.
What do you name your Maven projects?
There is no general rules, nor conventions. Use something that makes sense for your organization and your team. But as I said above, your initial assumption is not true and putting Java code inside a maven war module is a common practice (except for code you want to share between modules).
Not sure if this below link directly answers your question, but it makes sense to refer it
Refer their JIRA task here Document the naming convention for archetypes
As per this, the naming convention can be as below
The Artifact id of the archetype should be of the format -archetype-
Ex: + maven-archetype-quickstart : Which indicates the archetype is from maven and the project is a quick start
Same way you scala-archetype-simple : Which indicates it is from scala and is a simple scala project
Best of luck

How does the maven file structure work?

We are planning on restructuring a complex project with many modules/pieces, what ever you wanna call it. In order to move toward a standard directory structure, we would like to adopt the maven file structure.
So the big question is: Can anybody provide a description of the maven file structure, where we don't have to dig through all the maven speak?
Please see
http://maven.apache.org/guides/introduction/introduction-to-the-standard-directory-layout.html
src/main/java Application/Library sources
src/main/resources Application/Library resources
src/main/filters Resource filter files
src/main/assembly Assembly descriptors
src/main/config Configuration files
src/main/webapp Web application sources
src/test/java Test sources
src/test/resources Test resources
src/test/filters Test resource filter files
src/site Site
LICENSE.txt Project's license
README.txt Project's readme
BTW, we did that migration on existing projects.
It was a really long and hard task to make everything work as intended, but we are finally done and happy with it.
UPDATED
When you have many projects, you have the same structure for each project.
Now the real problem starts when you want to group them. We had a hard time reading Maven documentation and best-practices, and deciding what was the appropriate structure for us.
The basic idea would be to group related projects in a common directory (that we call a module), allowing to process the module as a whole without listing them. But if you open the module in an IDE (Eclipse in our case), the projects themselves belong to it, but are not opened as subprojects (that notion doesn't exist in Eclipse).
We ended up with a strict hierarchy, that freed us from many maven problems:
The actual coding projects (java projects) are always leaf in our directory tree. They are the only ones we open in the IDE. They are of type JAR, or WAR.
Their parents/modules are always of type POM. They have no java code.
I've been using the same approach as Jens on a number of projects both with Maven 2.2.1 and now with Maven 3.0-alpha-6: POM modules define the module structure of your project tree, JAR/WAR modules are the leaves of the tree. All modules have the same version.
Advantages:
You can
place properties or dependencies on
specific levels in the module
hierarchy and they will be inherited
to all sub-modules.
You can build
related modules simply by going to
the appropriate level in the tree and
running "mvn install" - Maven will
work out the correct build order
according.
Various Maven plugins such
as the release plugin rely on this
tree structure.
The latest Maven
Eclipse plugin can handle this
structure very well and will
represent the tree as a flat list.
There is an experimental feature in
the plugin which ensures that
so-called "shadowed" artifacts appear
only once which helps when searching
for resources in Eclipse.
Disadvantages:
Extension takes some time. For instance, if you decide that a JAR module requires sub-modules, you will need to convert the existing JAR module into a POM module and then distribute its contents to the newly created JAR sub-modules as POM modules cannot contain any code themselves.
All the POM modules will appear in Eclipse and can slow down the build somewhat. Hoever, you can close them and Eclipse will source them from the repository instead.