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Maven using wrong dependency version

The dependency version I want to use is 4.5.0 as specified in my pom.xml
<dependency>
<groupId>net.java.dev.jna</groupId>
<artifactId>jna</artifactId>
<version>4.5.0</version>
</dependency>
<dependency>
<groupId>net.java.dev.jna</groupId>
<artifactId>jna-platform</artifactId>
<version>4.5.0</version>
</dependency>
However, when I run mvn clean install -DskipTest=true. Maven will download and use version 4.2.2.
libraries
I tried searching in the entire project thinking maybe there are other files(in this case pom.xml) that specify the version to 4.2.2 but found nothing.
Has anybody encountered this issue before? I'm new to Java and I can't think of any other reason as to why this is happening.

Look at the output of mvn dependency:list. It will list you all dependencies of the project with their respective versions.
This is the truth. If your Eclipse or IntelliJ or whatever list something else, they are most certainly wrong/outdated.

Eclipse: exclude a 'runtime' maven dependency from the build path

I have a project that needs a dependency on iText 5.5.2 and on iText 2.1.7 (Primefaces needs this specific version at runtime and won't work with iText 5 due to license issues).
So I have this in my pom.xml:
<dependency>
<groupId>com.itextpdf</groupId>
<artifactId>itextpdf</artifactId>
<version>5.5.2</version>
<scope>compile</scope>
</dependency>
<!-- iText 2.1.7 is necessary at runtime to have the 'Export to PDF' function of Primeface work -->
<!-- It won't conflict with iText 5 as the packages are different -->
<dependency>
<groupId>com.lowagie</groupId>
<artifactId>itext</artifactId>
<version>2.1.7</version>
<scope>runtime</scope>
</dependency>
The problem is that I don't want our developers to be able to import classes from iText 2.1.7 (com.lowagie.* package). I want to force them to use classes from iText 5.5.2 (com.itextpdf.* package).
Although iText 2.1.7 is in 'runtime' scope, Eclipse still adds the jar file in the build path, allowing developers to import the wrong package (com.lowagie instead of com.itextpdf).
Is there a way to exclude it from the build path ?

Unfortunately it seems not to be possible on Eclipse with a normal build, it is a known bug, check Bug 414645 and Bug 376616. Eclipse (m2e) can't properly manage Maven dependencies scope.
However, if you place the runtime dependencies on a profile, then Eclipse will not add them to the classpath (the profile shouldn't be active by default, though). I just tested it on Eclipse Mars and it works perfectly.
Hence, in your case you could add to your POM:
<profiles>
<profile>
<id>runtime</id>
<dependencies>
<dependency>
<groupId>com.lowagie</groupId>
<artifactId>itext</artifactId>
<version>2.1.7</version>
<scope>runtime</scope>
</dependency>
</dependencies>
</profile>
</profiles>
As such, it can't be used to compile on Eclipse. However, your build would then need to use it at runtime, running with -Pruntime in this case.
Although adapting your POM and build to an issue of an IDE might not be ideal, it could be a good compromise to achieve your goal.

Missing plugins found while loading a transformation on Kettle

I receive this error whenever I run my extraction from the command line, not in the Spoon UI.
Missing plugins found while loading a transformation
Step : MongoDbInput
at org.pentaho.di.job.entries.trans.JobEntryTrans.getTransMeta(JobEntryTrans.java:1200)
at org.pentaho.di.job.entries.trans.JobEntryTrans.execute(JobEntryTrans.java:643)
at org.pentaho.di.job.Job.execute(Job.java:714)
at org.pentaho.di.job.Job.execute(Job.java:856)
... 4 more
Caused by: org.pentaho.di.core.exception.KettleMissingPluginsException:
Missing plugins found while loading a transformation
My maven dependencies is as follows.
<dependency>
<groupId>rhino</groupId>
<artifactId>js</artifactId>
</dependency>
<dependency>
<groupId>pentaho-kettle</groupId>
<artifactId>kettle-core</artifactId>
</dependency>
<dependency>
<groupId>pentaho-kettle</groupId>
<artifactId>kettle-engine</artifactId>
</dependency>
<dependency>
<groupId>pentaho-library</groupId>
<artifactId>libbase</artifactId>
<version>5.1.0.0-752</version>
</dependency>
<dependency>
<groupId>pentaho</groupId>
<artifactId>pentaho-big-data-plugin</artifactId>
<version>5.1.0.0-751</version>
</dependency>
<dependency>
<groupId>pentaho</groupId>
<artifactId>pentaho-mongodb-plugin</artifactId>
<version>5.1.0.0-751</version>
</dependency>
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>2.11.1</version>
</dependency>
<dependency>
<groupId>pentaho</groupId>
<artifactId>metastore</artifactId>
<version>5.1.0.0-751</version>
</dependency>
<dependency>
<groupId>pentaho-library</groupId>
<artifactId>libformula</artifactId>
</dependency>
<dependency>
<groupId>simple-jndi</groupId>
<artifactId>simple-jndi</artifactId>
</dependency>
<dependency>
<groupId>org.drools</groupId>
<artifactId>drools-compiler</artifactId>
</dependency>
<dependency>
<groupId>org.drools</groupId>
<artifactId>drools-core</artifactId>
</dependency>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
</dependency>
</dependencies>
Am I missing anything?

before init kettleEnviroment
KettleEnviroment.init();
you should add this code like
StepPluginType.getInstance().getPluginFolders().add(new PluginFolder("your plugins path", false, true));

Having the MongoDB plugin as a dependency only works for compilation. When PDI runs it looks for a plugins/ folder under the current directory, and will load all plugins from there. You can override the location by setting the KETTLE_PLUGIN_BASE_FOLDERS system property. Either way, you'll want a plugins/ folder and to unzip the MongoDB plugin package (not the JAR) into plugins/. That should put a folder called pentaho-mongodb-plugin under plugins/, and if PDI is pointing at that plugins/ folder, it should load and use the plugin successfully at runtime.

You must run Kitchen from Kettle installation directory.
As written here:
http://wiki.pentaho.com/display/EAI/Kitchen+User+Documentation
Please make sure that you are positioned in the Kettle directory
before running the samples below. If you put these scripts into a
batch file or shell script, simply do a change directory to the
installation directory

I had the same error message after an update from version 7 to 8.3. In my case, it was the step 'Abort' and 'Attend' that caused the error. In version 8 these two steps aren't part of the library "kettle-engine-8.3.0.0-371.jar" anymore, they are now part of the library "pdi-core-plugins-impl-8.3.0.0-371.jar" in a new plugin. I had to add the plugin in the maven-dependencies:
<dependency>
<groupId>org.pentaho.di.plugins</groupId>
<artifactId>pdi-core-plugins-impl</artifactId>
<version>8.3.0.0-371</version>
</dependency>
But that was still not everything, I still got the error message. The reason: "To use non-native plugins with an embedded Pentaho Server, you must configure the server to find where the plugins reside" (https://help.hitachivantara.com/Documentation/Pentaho/8.0/Developer_Center/PDI/Embed).
So above the line KettleEnvironment.init() in my java-code, I added this one:
System.setProperty("KETTLE_PLUGIN_CLASSES", "org.pentaho.di.trans.steps.abort.AbortMeta,org.pentaho.di.trans.steps.append.AppendMeta");
KettleEnvironment.init();
This way worked for me. There's also a suggestion using a plugin-folder (see the link or the other answers) and working with KETTLE_PLUGIN_BASE_FOLDER instead.
Unfortunately, the error message doesn't mention which plugin is missing. I deleted and added them (in my local Spoon application) until I found exactly the one that was missing.

Just edit spoon.sh and add
OPT="$OPT -DKETTLE_PLUGIN_BASE_FOLDERS=$BASEDIR/plugins"
right after the line where the OPT variable is set.
This is actually the solution from mattyb. Editing spoon.sh will fix the problem for good.
Another solution is to create a symbolic link in your ${KETTLE_HOME}/.kettle directory which points to the plugins folder.

Java EE Provided dependencies in Hudson / Jenkins

I'm trying to build a Maven based Java EE project on Jenkins, but I'm getting compilation errors. The reason seems to be that the Java EE dependencies that are marked as provided in the POM logically enough aren't downloaded when the project is built.
How can I set up the POM so that the build works in Jenkins, but the EE dependencies aren't included in the WAR file?
My thanks in advance for any input you can provide.

That's strange, AFAIK the dependencies with scope "provided" are simply not placed in the built file, they should however be downloaded. Are you sure your Maven is correctly configured to download dependencies - maybe there's a proxy that's not configured.

Not sure if its the best solution, but you can add EE dependencies with scope "provided", like the example:
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-servlet-api</artifactId>
<version>7.0.27</version>
<type>jar</type>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.el</groupId>
<artifactId>javax.el-api</artifactId>
<version>2.2.4</version>
<type>jar</type>
<scope>provided</scope>
</dependency>
Maybe there is a plugin who provides all of them to you, but I'm not sure about that.
Hope that helps

Maven error when resolving dependency

I am new to Maven and am trying to set up one of my first POMs. My application will cache using EhCache. Going to Maven Central Repo (link here) I copy-n-pasted the <dependency> tag and copy it into my pom.xml like so:
...many dependencies above this point
<dependency>
<scope>compile</scope>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.0.1.Final</version>
</dependency>
<dependency>
<scope>compile</scope>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache</artifactId>
<version>2.5.0</version>
</dependency>
<dependency>
<scope>compile</scope>
<groupId>jasperreports</groupId>
<artifactId>jasperreports</artifactId>
<version>3.5.3</version>
</dependency>
...many dependencies below this point
When I save the changes, Eclipse builds the workspace and gives me an error on the opening <dependency> tag for EhCache 2.5:
Missing artifact net.sf.ehcache:ehcache:jar:2.5.0
So I figured that perhaps v.2.5.0 has something wrong with it, and repeated the same for 2.4.7 (the last 2.4.x release before 2.5.0). Same deal.
Since I'm so new to Maven, I don't even know where to begin looking. I tried Project >> Clean and even restarted Eclipse to see if it was just a typical Eclipse "quirk". Nope.
I am thinking:
Could EhCache be publishing bad JARs to the Maven repo?
Could Maven Repo have something wrong with it?
Could this be due to something else configured wrong in my pom.xml?
Could this be a "JAR hell" issue where I have a conflict somewhere on my dependency graph?
How would SO start tackling this problem? Thanks in advance!

It is usually safer to refer to search.maven.org. Dependency from there:
<dependency>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache</artifactId>
<version>2.5.0</version>
<type>pom</type>
</dependency>
Mind type pom. From module's pom:
This is a pom artifact to pull in ehcache-core and ehcache-terracotta
for clustering. Make sure to set 'type' to 'pom' in your dependency.
Aparently when someone does not need terracotta, ehcache-core will do perfectly fine as other answer states.

They use ehcache-core in the official documentation. Maven Central does not have a jar artifact for ehcache 2.5 which explains your error message.
Using ehcache-core changes the dependency to:
<dependency>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache-core</artifactId>
<version>2.5.0</version>
</dependency>
Which successfully downloads on my machine (ehcache does not).

I dropped this into IntelliJ and it found it. I suspect there is something wrong with your settings. Try creating a project with only this dependency in it. If it fails to download, I would check your setting. e.g. .m2/settings.xml Are you using a Nexus server or maven proxy/cache?
BTW: A simpler way to search for JARs is to use http://mvnrepository.com/ which will find all the available versions and show you the XML you need to add.