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Serial execution of plugins in Maven using <phase>

I have the following structure in pom.xml:
<profile>
<id> x </id>
<build>
<finalName> y </finalName>
<plugins>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<!-- DELETE SOME FOLDERS AND SOME FILES -->
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<!-- MOVE A FILE -->
</plugin>
<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<version> 1.6 </version>
<executions>
<execution>
<phase> <!-- WHAT COMES HERE ? --> </phase>
<configuration>
<!-- I EXECUTE CMD FILE HERE -->
</configuration>
<goals>
<goal> run </goal>
</goals>
<execution>
<executions>
</plugin>
</plugins>
</build>
</profile>
I want to achieve a serial execution for plugins:
Delete some folders and some files (1st plugin)
Move a file (2nd plugin)
Run cmd file (3rd plugin)
What should I use for <phase> to have the order above (sequential execution)? Is it relevant ? Is it ok to use pre-integration-test for example ?
P.S.: Here are the phases: http://maven.apache.org/ref/3.2.2/maven-core/lifecycles.html

Maven doesn't support adding steps to the life cycle (without writing a new plugin).
If you have complex build steps and you absolutely need a certain order and this order violates the standard life cycle, then Maven might not be the right tool for you. Consider Gradle instead.
If you have to use Maven, then stop using plugins for this. Instead, replicate all the build steps using the antrun plugin so everything is done with a single Ant script. Afterwards, find a place in the life cycle where you want all the steps to be executed at once.
generate-sources is a good place if you need something to be done before anything is compiled. If you want to run code after compilation and tests, use prepare-package.
See here for the complete life cycle: http://maven.apache.org/guides/introduction/introduction-to-the-lifecycle.html#Lifecycle_Reference

If you like to add the execution of different plugins to the same life cycle phase the execution order is defined by the order of the definition in the pom file.
So if you choose to bind all the above three plugins to the package phase than they will be executed in the given order.
You can of course use the antrun plugin which will work also and will implicit execute the steps in the defined order without thinking about the default behaviour of Maven.
You can also use the exec-maven-plugin to execute a script in a particular life cycle phase but which might be not a good solution cause the script is OS dependent. Or you can use the groovy plugin to execute some steps in groovy code.

Issue setting the class path in Maven exec plugin when running a Main Class

I have embedded Jetty in my application. In order to automatically execute my integration tests on my build server I'd like Maven to start my application in the pre-integration-test phase. The integration tests are in another project than the application te be tested, because the tests are of a quite complex nature and should be seperated from production code.
I have tried to set up my application using the Maven exec plugin, but keep running into ClassNotFoundErrors. I use the maven-dependency-plugin to copy all dependencies to target/lib/. Until now, I haven't been able to figure out how to tell the exec plugin to add that lib folder to the class path.
This is my current exec plugin configuration:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<executions>
<execution>
<id>default-cli</id>
<phase>pre-integration-test</phase>
<goals>
<goal>java</goal>
</goals>
<configuration>
<mainClass>com.zertificon.managementCenter.adminUi.server.WebApp</mainClass>
<!-- this does not work: -->
<classpath>${project.build.directory}/${libFolder}/</classpath>
</configuration>
</execution>
</executions>
</plugin>
The WebApp class I am trying to run originates from another Project and is installed in the local repository. I would highly apreciate any help.

Found the error: I have been using Jetty together with a Selenium Library that itself bundles Jetty, too. This lead to a wrong Jetty Version being loaded wich gave me class not found errors. Go figure.

Mechanics of Goal execution in Maven

I have the wsimport plugin in my project.
I would like to execute the wsimport. According to the website, the string to execute is "mvn jaxws:wsimport".
Firstly, is this string deductable from the XML ?
The artifact ID is :
<artifactId>jaxws-maven-plugin</artifactId>
and goal :
<goal>wsimport</goal>
so is the artifact-part just the substring of the artifactid leading up to "-maven-plugin" ?
..And when I execute my plugin goal "mvn jaxws:wsimport" does this completely ignore which phase I am in? Ie. is this running outside of the phase? And if no, is there a way to run this standalone?
ie. is there a way I can set the phase to none? (eg [phase]none[/phase]).
Pom code :
<build>
<plugins>
<plugin>
<groupId>org.jvnet.jax-ws-commons</groupId>
<artifactId>jaxws-maven-plugin</artifactId>
<version>2.3</version>
<executions>
<execution>
<id>wsimport-from-jdk</id>
<goals>
<goal>wsimport</goal>
</goals>
<configuration>
<executable>${tool.wsimport}</executable>
<wsdlUrls>
<wsdlUrl>http://WorkPC:8080/server-web/AirlineWS?wsdl</wsdlUrl>
</wsdlUrls>
<packageName>com.bluewalrus</packageName>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>

When you issue a command like mvn [plugin]:[goal], it launches Maven out of any lifecycle, so if you do not intend to perform that goal inside a lifecycle, but only via such commands, you shouldn't have any <execution> defined, just place <configuration> right after <version>.
About how Maven can shorten the plugin call (i.e. mvn dependency:tree instead of mvn org.apache.maven.plugins:maven-dependency-plugin:2.1:tree), it is based on several conventions:
When no version defined, it tries to take the latest from available repositories
When the groupId is omitted, it looks among the predefined or user-defined pluginGroups to find a suitable one. See here for more information (Configuring Maven to Search for Plugins)
On the same page, you can see how plugins prefixes are used to shorten the plugin prefix, by using a prefix instead of the artifactId of the plugin. Thirdparty plugins should use [prefix]-maven-plugin construction, and it looks OK here.
And to disable the default execution of a plugin (although it might not be useful in this case), you can use this answer

Running caliper from eclipse in maven's test scope

I have a Java project in Eclipse, with JUnit tests in my src/test directory. I've also added a class to my tests with Caliper microbenchmarks, and I'd like to be able to run these tests from within Eclipse.
As the Caliper code is test code, I've added Caliper as a dependency in Maven in test scope. That makes it show up in the classpath when I run JUnit tests, but I can't see a way to run an arbitrary class with test dependencies in the classpath. What I tried doing was adding a new Run Configuration for a Java Application, thinking I could launch CaliperMain with the right class as a parameter, but the Caliper jar is not on the classpath and I can't see how to add it.
I don't want to move my benchmark code and dependency into the main scope, as it's test code! It seems seriously overkill to move it into a completely separate project.

You should be able to do this with the Maven Exec Plugin. For my project, I opted to make a benchmark profile that can be run with the maven command mvn compile -P benchmarks.
To configure something like this, you can add something along the lines of the following to your pom.xml, specifying scope of the classpath as test using the <classpathScope> tag:
<profiles>
<profile>
<id>benchmarks</id>
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<executions>
<execution>
<id>caliper</id>
<phase>compile</phase>
<goals>
<goal>java</goal>
</goals>
<configuration>
<classpathScope>test</classpathScope>
<mainClass>com.google.caliper.runner.CaliperMain</mainClass>
<commandlineArgs>com.stackoverflow.BencharkClass,com.stackoverflow.AnotherBenchmark</commandlineArgs>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</profile>
</profiles>
Alternatively, if you'd like to specify a lot of options for caliper, it is probably easier to use the <arguments> tags:
<executions>
<execution>
<id>caliper</id>
<phase>compile</phase>
<goals>
<goal>java</goal>
</goals>
<configuration>
<classpathScope>test</classpathScope>
<mainClass>com.google.caliper.runner.CaliperMain</mainClass>
<arguments>
<argument>com.stackoverflow.BencharkClass</argument>
<argument>--instrument</argument>
<argument>runtime</argument>
<argument>-Cinstrument.allocation.options.trackAllocations=false</argument>
</arguments>
</configuration>
</execution>
</executions>
More configuration options (like -Cinstrument.allocation.options.trackAllocations above) can be found here and more runtime options (like --instrument above) can be found here.
Then, if you are using the Eclipse m2 Maven plugin, you can right-click on your project folder and select Run as... -> Maven Build... and enter something like clean install in the Goals input box and benchmarks in the Profiles input box and click Run and you should see the output in your Eclipse console.
It's important to note that I used a local snapshot build of Caliper by checking out the source using git clone https://code.google.com/p/caliper/, which is recommended at the time of this post in order to take advantage of the latest API.

Can Maven collect all the dependent JARs for a project to help with application deployment?

I'm just starting to use Maven, (evaluating it, really) and I need to be able to quickly generate a JAR file for my application and a directory with all the dependencies (for example, lib) so that I can deploy those two to be run in a stand-alone manner. Generating the JAR file with the proper manifest is easy, but I do not know how to get Maven to copy the dependencies for the current project into a lib directory that I can deploy.
Since this is for a stand-alone Java applications, I am not interested in deploying to a Maven repository, that is also fairly trivial, or at least easily googleable.
I've found out how to do everything except copy the dependent JAR files into some specified directory. This is the workflow I'm looking for:
$ mvn clean
$ mvn package
$ cp -r target/{lib,myApp.jar} installLocation
Then, running myApp.jar from installLocation as a JAR file should "just work" regardless of my $CLASSPATH.
To try and pre-empt some answers:
I do have a Main-class: set, and it works fine.
I've also set the classpath in the MANIFEST.MF, and that works fine too.
I've found out how to use <classpathPrefix> and <classpathMavenRepositoryLayout> to make this work -- but only on my machine. (via: <classpathPrefix>${settings.localRepository}</classpathPrefix>)

What you want to investigate is Maven's dependency plugin. Add something similar to the following to pom.xml:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<configuration>
<outputDirectory>
${project.build.directory}
</outputDirectory>
</configuration>
</plugin>
Then run mvn clean dependency:copy-dependencies to copy perform the copy. Combine this with the assembly plugin and you can package everything into a self contained archive for distribution.

I did not care for the Shade plugin since it rolls all the packages from all the jars together.
To include all of the external libs you can use the Dependency Plugin as mentioned above.
This example will create a "lib" directory under "target/classes" before the "package" phase.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.6</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>prepare-package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>target/classes/lib</outputDirectory>
<overWriteIfNewer>true</overWriteIfNewer>
<excludeGroupIds>
junit,org.hamcrest,org.mockito,org.powermock,${project.groupId}
</excludeGroupIds>
</configuration>
</execution>
<execution>
<phase>generate-sources</phase>
<goals>
<goal>sources</goal>
</goals>
</execution>
</executions>
<configuration>
<verbose>true</verbose>
<detail>true</detail>
<outputDirectory>${project.build.directory}</outputDirectory>
</configuration>
</plugin>

Take a look at maven's dependency plugin, specifically the copy-dependencies goal. The usage section describes how to do exactly what you want.
To do it from the command line just do:
$ mvn dependency:copy-dependencies -DoutputDirectory=OUTPUT_DIR

Yet another one is appassembler plugin
What I like about it is that it packages the app in a form ready to use (with a .bat file ans such)

It sure can. You need to use the shade plugin which can be done by adding
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>1.3-SNAPSHOT</version>
<configuration>
<!-- put your configurations here -->
</configuration>
</plugin>
to your project.

Using maven.repo.local one can collect all jars, but, they are collected into a directory with maven hierarchy (.m2).
mvn install -Dmaven.repo.local=./pick/some/folder
You can then collect them (on Linux):
mkdir flat-repo
find ./pick/some/folder -type f -name "*.jar" | xargs -I'{}' cp '{}' flat-repo/