Develop Reference

Recompiling third party Java code in a restricted environment

I have user-level access to Jenkins and cannot change the settings.xml for Maven due to access restrictions. When I want to mvn deploy, it expects to have a distributionManagement clause in the pom.xml. The code however comes from the internet and I rather don't change the pom.xml every time. Is there something I can do in Jenkins? I am considering using the Artifactory plugin because that is where I want to deploy.

I'd recommend using mvn deploy from Jenkins, but specifying the repository to deploy to with the -DaltDeploymentRepository=id::layout::url system property.
Format: id::layout::url
id is the repository id to be used to get credentials from the settings.xml (i.e. central, snapshot)
layout should be "default", unless you are still using Maven1 (in which case it should be "legacy")
url is the URL for the repository you want to deploy to.
This is specified in the Maven documentation here: https://maven.apache.org/plugins/maven-deploy-plugin/deploy-mojo.html

The Artifactory plugin seems a good solution if you cannot use the Maven deploy goal.
With a simple mvn clean install command + the Artifactory plugin, you will be able to deploy where you want (if the Jenkins server has the relevant read/write access):

Maven global plugin configuration

I'd like to have a plugin configuration that will not exist inside the pom.xml file (and also in any project files).
What I want to do is to have a plugin that will be used only by me on my workstation. Specifically, I want to deploy my project onto the Tomcat 7 container and for this I want to use Apache Tomcat Maven Plugin, but since different developers may want to use different servers or entire ways of deployment I don't want to put this configuration into the pom.xml.
Is it possible in Maven to have such global/user-specific plugin configuration?

There are several workarounds that I can think of.
in the pom.xml a specific set for where you define your way of deployment.
ex: mvn goal -P{PROFILE_NAME}
you can just put the plugin normally in pom.xml and just don't push the changes on the repository, so it won't be available for other developers.
But the assumption seems kind of wrong, if you many developers want to work on the same project they should use the same container for deployment for persistence or if you really want to do it like this, I think the cleanest way would be for every developer to use maven profiles. And in your local settings.xml (USER_HOME/.m2/settings.xml)
just set the profile as default:
(...)
<activeProfiles>
<activeProfile>{YOUR_USER_PROFILE}</activeProfile>
</activeProfiles>
(...)
so you don't need to always specify at command line when running mvn your user profile.

Travis CI not using extra Maven repository provided in pom.xml

I have a Java-based GitHub project, fitnessjiffy-spring (I'm currently focused on the "bootstrap" branch). It depends on a library built from another GitHib project, fitnessjiff-etl. I am trying to configure both of these to be built by Travis CI.
Unfortunately, Travis is not as sophisticated as Jenkins or Hudson in dealing with Maven-based Java projects. Jenkins can easily handle dependencies between projects, but the same concept doesn't seem to exist with Travis. If one project depends on another, then that other project must already be built previously... and its artifact uploaded to some Maven repo where the first project can download it later.
My "fitnessjiffy-etl" library is building and deploying just fine. I'm using Bintray for Maven repository hosting, and you can clearly see my artifacts over plain HTTP at:
http://dl.bintray.com/steve-perkins/maven/
In my "fitnessjiffy-spring" project, I am adding this Maven repo location directly in the pom.xml, so that Travis will be able to find that artifact dependency. Here is the state of my POM at the time of this writing. Note the <repositories> element at the bottom of the file.
When I build this project locally, it works just fine. I can see it downloading the Maven artifact from "http://dl.bintray.com/...". However, when I try to build on Travis CI it fails every time. I can see in the console log that Travis is still trying to download the artifact from Maven Central rather than my specified repo.
Does this make sense to anyone else? Why does Maven utilize a custom repository location in a POM file when building locally, but ignores this configuration when running on a Travis CI build?

From digging into this further, I discovered that Travis uses its own proxy for Maven Central, and has configured Maven to force ALL dependency requests through their proxy. In other words, it does not seem possible at this time to use additional Maven repos specified in the POM file of a project built on Travis.
In my case, I ended up refactoring such that project would not need the outside JAR dependency. I also switched to Drone.io, so I could manage my settings on the build server rather than having to carry a YAML file in my repository (which always struck me as a bit daft).
However, even on Drone it's still a major hassle to manage dependencies between multiple projects (extremely common with Java development). For Java, I just don't think there's currently an adequate substitute for Jenkins or Hudson, maybe running on a cheap Digital Ocean droplet or some other VPS provider instance.

In your install phase add a $HOME/.m2/settings.xml define your custom repository.
cache:
directories:
- "$HOME/.m2"
install:
- curl -o $HOME/.m2/settings.xml
https://raw.githubusercontent.com/trajano/trajano/master/src/site/resources/settings.xml
- mvn dependency:go-offline
script:
- mvn clean install site

Jenkins building for different environments

I currently have a Jenkins instance installed on a Development box. This builds fine and deploys to our development environment without any issues.
During the build process my project makes use of a single properties file containing details such as a database connection URL (Details such as these will obviously vary depending on the environment I'm pointing to).
What I would like to know is what is the best way to configure my project so that when I want to release to Production the WAR file built by Jenkins contains the Production properties instead of Development?
(Note I am also using Maven in my project).

I know 3 options:
We have used maven.-profiles for that in the past, but they have the disadvantage, that the release-plugin of maven doesn't work with profiles, so we had to change the versions manually and were unable to deploy the artifacts in a remote repository like nexus.
Another Option is mavens assembly-plugin. That can be used together with the release-plugin, as far as I know.
We decided to write a simple tool that changes the war-files after the maven-build process. It runs in a seperate Jenkins-Job. The Idea is, that building and configuring are two seperate steps. The Artifacts comming out of maven are always in a default-configuration. And if we need the configuration for the production release we start a jenkins job that does the configuration of the war-files.

You can create different maven profiles, like dev, prod, then in the profile setting, use/filter the corresponding resource files like .../(dev|test|prod)/project.properties And in Jenkins, when you build for different platform, build with -Pdev or -Pprod to get the war for the right target.
You may want to check maven profile, maven resource filtering for detailed configuration.
something not related, connect Database via jndi if possible.

Standard way of deploying maven projects

I have two maven projects, which I need to deploy through automatic deployment process. (like nightly build or similar)
Scenario is as:
mv-proj1
-dependency-1.jar
-dependency-2.jar
-dependency-3.jar
mv-proj2
-dependency-3.jar
-dependency-4.jar
-mv-proj1.jar
sources of mv-proj1 and mv-proj2 can not be disclosed.
mv-proj2 is executable jars and provide services to other application modules.
So what is the standard way of deploying these to production machine or lets say UAT machine?
Do I need to set up intra-organization maven repository?
Do I need to install maven repository to UAT machine?
One possible way I could think is to set up and host intra-organization maven respository as well as setting up maven on UAT machine to fetch data from intra-organization maven respository. and deploy only pom.xml.

I would let my choice depend on what the consumers of your artifacts are.
If the consumers are also Maven projects that can pull in your JARs from said intra-organizational Maven repository, that's definitely a great way to go. I believe that every organization that is serious about using Maven is sooner or later going to have use cases for such own repository anyway. I've worked with Artifactory and Nexus and feel that both are great products (and free beer for the use case as stated here). They're both easy to install, and it should not be an exploration that is daunting, go for it!
If your UAT machines would use Maven to build and install anything that pulls in your artifacts as a dependency, them would be running Maven client-side. There would be a local repository (artifact cache) on these clients, but that's a different beast than the organizational repository mentioned above, which you would likely deploy not on the actual UAT machines.
If mv-proj2 is rather a "final delivery", executable as you say, you may want to pack it all up as a nice, single JAR (Maven can do that for you) and distribute that to your users. You could do that again through an organizational repository. You could ultimately release it to some network drive or web server. Many ways to do so, e.g. use maven-jar-plugin with outputDirectory pointing to wherever you want to release.