I have a multi-module maven project where we shade Google's Guava to relocate the packages into our package tree so that we don't have to worry about version conflicts. I understand that this is a fairly common practice.
Building the jar works fine as does building the system generally. However, when executing the site:site target in Maven it calls compiler:testCompile and at this point the relocated classes can not be found. Let me point out that the earlier testCompile worked just fine.
I suspect that this is because the maven shading project is a peer of the project that fails and that during the second testCompile execution it finds the shading project, looks and finds no classes to compile against and so dies. There is a properly named shaded jar in the target directory and it does contain the classes that are being looked for.
What I think I want to know is: Is there a mechanism to tell maven to look for the jar in the sub-module (the source never existed there) and skip the compiled classes? I suppose as a last resort I could extract the contents of the just built jar into the target/classes directory so they can be found.
Any assistance would be appreciated.
We had the same problem in the past. And ended up with a separate release cycle for shaded artefact and other modules, while they were kept in the same repo:
/pom.xml - root for all child modules, except the shaded one
/shaded/pom.xml - no ref to parent (no <parent> section), own release cycle
/module1/pom.xml - explicit ref to released version of shaded artefact
...
/moduleN/pom.xml
In IDE these files /pom.xml and /shaded/pom.xml were imported as separate projects.
This becomes even more useful later, when re-building shaded modules actually happened only several times a year.
We have the next project structure:
parentPom.xml
java projects
streambase projects
streambaseParentPom.xml
project1
project2 (has dependency of project1)
So we have a parentPom with inherits to streambaseParentPom and last one inherit to all streambase projects.
So, we make attemp to have in parentPom a properti called cerebro.version which define the version for parent.
We're getting issues when we have project1 as dependency of other projects, we're getting next error message:
[ERROR] Failed to execute goal on project eFX-SB7-Pricing: Could not resolve dependencies for project com.santander.fx:eFX-SB7-Pricing:jar:3.14.10.0.4-SNAPSHOT:
Failed to collect dependencies at com.santander.fx:eFX-SB7-Common:jar:3.14.10.0.4-SNAPSHOT:
Failed to read artifact descriptor for com.santander.fx:eFX-SB7-Common:jar:3.14.10.0.4-SNAPSHOT:
Could not transfer artifact com.santander.fx:eFX-SB7-Parent:pom:${cerebro.version} from/to eFX-External-Repository (http://lnx-efxbuild2.ants.ad.anplc.co.uk:8081/artifactory/ext-release-local):
Illegal character in path at index 109: http://lnx-efxbuild2.ants.ad.anplc.co.uk:8081/artifactory/ext-release-local/com/santander/fx/eFX-SB7-Parent/${cerebro.version}/eFX-SB7-Parent-${cerebro.version}.pom -> [Help 1]
Thanks in advance.
I am afraid it doesn't work like that. It is a bad idea to parameterize the <version> value since even if you managed to deploy it to your remote repo, any project using that artifact later on wouldn't have a clue what ${cerebro.version} should resolve to.
Remember, Maven works hard to keep your builds reproducible. If the build is dependent on some variable that was known at deploy time, but unknown for dependents, your build will no longer be reproducible.
I want to use Jmathplot.jar
I tried to put it as a dependency
<dependency>
<groupId>jmathplot</groupId>
<artifactId>jmathplot</artifactId>
<version>1.0</version>
<scope>system</scope>
<systemPath>${project.basedir}/lib/jmathplot.jar</systemPath>
</dependency>
but when installing I get this error:
Some problems were encountered while building the effective model for com.NResearch:dable-start-tRisk:jar:0.1-SNAPSHOT
[WARNING] 'dependencies.dependency.systemPath' for jmathplot:jmathplot:jar should not point at files within the project directory, ${project.basedir}/lib/jmathplot.jar will be unresolvable by dependent projects # line 44, column 19
How can I get around this please?
EDIT1:
I cannot change Maven to include all dependent jars into a single jar. As this is uploaded to a web project.
"Dependent" is using your project, "dependency" is used by your project.
The real error here is that jmathplot.jar is in a folder that can really only reliably be found by your project. Even though your dependents know how to find your artifact in the local repository, they won't know where the sources are for your artifact, hence won't be able to find lib/jmathplot.jar. You can fix that by changing the systemPath to an absolute path. It can still be parametrized, but then please use properties rather than implicit properties (such as ${project.basedir}.
It'd be better to get rid of the systemPath dependency, by installing jmathplot into a company repository, so it can be used alike 'normal' artifacts. But that may not be a useful option if you have to distribute your artifact out of the reach of your company repository. It would even be better if jmathplot would just get deployed to the Maven central repository.
As a last resort you may choose to bundle the dependencies (not the dependents). You can do this:
Using the Maven Shade Plugin. It lets you choose which packages to include which may be useful to bundle only jmathplot (and not other dependencies).
Using the Maven Assembly Plugin. It has a predefined descriptor for "JAR with dependencies" which would fit your use case. You could create your own descriptor off of that example and set dependencySets.dependencySet.scope=system to only include the system dependencies that are giving you trouble.
Best way is to install your dependency on your local repository. To do this:
1) using project source, install to local repository using mvn install
2) if you don't have source code, install to local repository using this
hope it's help
nota: you are spamming around this question, do you ? (see here: JMathPlot what is the Maven dependency code please )
I have a web project and a pom.xml file. It has enough dependencies to compile and package but not enough to start the project. In my IDE it's shown that everything is ok, but when a start the application it has errors. When i add external pom.xml from another app, my application launches.
So is there any way i can find out which dependencies are missing and how in future i can determine which dependencies are needed for using this or that?
You can use mvn dependency:analyze for determining which dependencies are used and declared or used and undeclared or unused and declared.
For more information refer to: http://maven.apache.org/plugins/maven-dependency-plugin/analyze-mojo.html.
Hope this helps.
There's no maven command to accomplish this. You need to check which classes are causing NoClassDefFoundError, figure out the dependency (Google) - which JARs they are shipped in, and add them with the runtime scope in your pom.xml.
In web projects specifically you oftentimes compile against servlets or Java EE specification JARs (they would only contain interfaces), but you need actual implementation JARs to be present in runtime. These JARs are typically and presumed to be available in the container you are running in (like Tomcat or JBoss), in this case they would be marked as provided scope in your pom.xml.
You need to check the NoClassDefFoundError in your output logs and add dependencies accordingly.
The best resource to search for missing dependencies is Maven Central Repository
To get a detailed debug log of your build, use -X in the command line.
You can check The dependency tree of your project by following command - mvn dependency:tree. This will only list the information about the deoendencies listed in your pom.xml More on it here
should be able to do it with :
maven dependency resolve
When I open a POM file and click on the "Dependency Hierarchy" tab at the bottom, it gives me the error, "Project read error". It works with other projects in the same workspace, just not with this one. Any ideas?
EDIT
In response to #Yhn's answer.
Running the compile and package phases outside of Eclipse from the command-line work as expected. It compiles the application and builds the final WAR file.
Eclipse is indeed pointing to the default location of the Maven settings.xml file, so it should be aware of the custom repositories that are defined in it (my company has its own Maven repository).
I can open and edit the POM file from Eclipse, so it must have read/write permissions to the file.
The project is not configured in Eclipse as a Maven project, so I cannot run the package phase from Eclipse (I can only run it from the command-line).
I wonder if it has anything to do with the fact that I was having trouble building the project with Maven 3 because apparently some of the transitive dependencies are configured for Maven 1, which Maven 3 does not support (this is my theory anyway, based on some of the error messages). I can build the project with Maven 2, but I still get messages such as the following:
Downloading: http://dist.codehaus.org/mule/dependencies/maven2/org/codehaus/xfie/bcprov-jdk14/133/bcprov-jdk14-133.pom
[INFO] Unable to find resource 'org.codehaus.xfire:bcprov-jdk14:pom:133' in repsitory mule (http://dist.codehaus.org/mule/dependencies/maven2)
It must be able to find these dependences however, because it downloaded the JARs just fine and can build the application. It seems like the problem is that the dependencies don't have POM files associated with them, which is maybe why they cannot be used with Maven 3. This might also be why I cannot view the Dependency Hierarchy in Eclipse.
EDIT 2
I converted the project to a Maven project by going to "Configure > Convert to Maven Project". When I open the POM file, I see the error:
ArtifactDescriptorException: Failed to read artifact descriptor for woodstox:wst (Click for 140 more)
(woodstox:wst is another transitive dependency of the project). An error appears in the "Markers" view for seemingly every depedency and transitive dependency in my project. However, I can successfully build the project by doing a "Run As > Maven build". (Edit: This might be because this project has no Java source code, but the JARs of the dependencies correctly appear in the final WAR.) The Dependency Hierarchy still gives the same error--"Project read error".
About the "Unable to find resource" messages--but this only appears for a handful of transitive dependencies. The project has many more transitive dependencies, but these messages do not appear for them. It seems like, because the dependencies do not have POM files, that Maven tries to search for them every time the project is built. Is this normal not to have POMs??
How might I go about getting a repo manager? Is this something that would have to be installed on the company's Maven repository or can you install it on your own workstation?
I had this problem with some non-maven jars that I needed to include in my maven project. I put the jars in my local repository using this maven command:
mvn install:install-file -Dfile=/test/gov.nist.xccdf-1.2.jar -DgroupId=gov.nist -DartifactId=xccdf -Dpackaging=jar -Dversion=1.2
Then I referred to them as dependencies in my pom.xml:
<dependency>
<groupId>gov.nist</groupId>
<artifactId>xccdf</artifactId>
<version>1.2</version>
<type>jar</type>
<scope>compile</scope>
</dependency>
This worked fine for a while, but I must have upgraded something in eclipse, and I started getting the error you describe.
The fix is to take them out of the local repository, and redo the install-file asking maven to generate a pom for you:
mvn -DgeneratePom=true install:install-file -Dfile=/test/gov.nist.xccdf-1.2.jar -DgroupId=gov.nist -DartifactId=xccdf -Dpackaging=jar -Dversion=1.2
The command will cause a pom to be generated in the same directory (within your local repo) where the jar is placed.
In recent versions of eclipse maven support, the maven build is still done with maven 2 (if you right-click your pom.xml, choose run as mvn package for example). The dependency analysis is now done with an embedded maven 3 plugin, which doesn't like a dependency that has no pom.xml.
I had the same problem. If you made your project a maven project, you should run:
Right Mouse Click on project | Maven | Update Dependencies or
Right Mouse Click on project | Maven | Update Project Configuration
That worked for me.
Given the information through the comments:
mvn compile/mvn package work through console (I'm assuming outside of eclipse). Based on that, the POM file should be correct and dependencies can be resolved.
However; it could be that eclipse's settings aren't correct. For example, if eclipse has some own maven properties (instead of the default ~/.m2/settings.xml file); I can imagine it to fail resolving dependencies configured in the settings.xml used by maven itself. The settings for this should be in the Eclipse Preferences # Maven > User Settings.
Also make sure that Eclipse can actually read the file (not locked, correct rights, etc).
Should this seem to be correct; can you try to run the mvn goal compile from eclipse? You can do this by right-clicking the project and selecting run as > maven package. That way it should run maven with the same settings as eclipse is using, and might show any additional errors in it's configuration.
--
In response to additional information:
Basically it tells you - when using Maven 2 - that it can't find a dependency resource (in this case bcprov-jdk14) in the given repository (codehaus/mule). When I search that maven module (bcprov-jdk14) I find it in the Maven central repo (through our local nexus) # repo1.maven.org/maven2. Maybe that causes the error you're getting with Maven2?
And as the Maven 3 doc says; for Maven 1.x repo's; you should proxy them through a repo manager that can serve it to you as a maven 2 repository (I believe we do that here too for some repo's through Sonatype Nexus OSS)
ps.: Enabling maven dependency management in eclipse should be enough to be able to use maven run targets; if you would want to test it.
--
Sound like it can be multiple problems... given that the normal maven build works fine, one would think that maven can at least get the artifacts it depends upon and their dependencies... Yet, eclipse doesn't seem to be able to.
Double check if your Eclipse internet connection settings are correct? Since you were talking about a company repo, I'm assuming there will probably also be a proxy (I had to set up my Eclipse to use that one too; though for plugins (see next point)).
Another possibility, from experience, can be a rule-based proxy block on *.pom url requests (our proxy here blocks that to force usage of the local repo manager, how evil and annoying that is :(). You might want to try and open the .pom file it tries to download manually in your browser to see if this is the case (I can't, for example...).
To get the repo set up, you would probably have to ask the one responsible for the repository to add it as a maven2 proxy.
At the very least, it seems Eclipse is having issues getting the dependency poms (which are needed to build the dependency tree) from the internet. You could always try to ask some ICT crew (if they are capable enough...) about it at your company, maybe they have some useful hints.
right click on the project, Maven->Update Project->Tick "Force Update of Snapshots/Releases"
I had the same problem when I added a new dependency to pom.xml without network connection. After this, I had so many problems such as "Missing artifacts", "Missing Descriptor", or "Project Read error". I solved this
delete the bad dependency just added from local repository.
rebuild local index.
re-add the dependency
<properties>
<!-- ********************** -->
<!-- Plugin's properties -->
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.7</java.version>
</properties>
this pom setting worked for me
Usually this happens if there is a typo in the pom that Maven cannot understand and then it throws Project read error. Like in my case I copied a maven dependency snippet and I by passed the version. Instead of typing the actual version # it was getting it dynamically ${asciidoctorj.version} and my pom didn't have this in the properties section. So I got this error. Once I removed that and put a version number it started working.
I had this after copying a local repository folder from another machine. The fix was to go into the repository folder I copied and delete
_remote.repositories along with the 'LastUpdated' files then refresh the Maven dependencies in Eclipse (Alt+F5)
I faced same situation today. In my case it's caused by dependency name in wrong case. E.g.
Project A -> Project B -> Project C
In project B's pm file, I mistakenly specified the dependency artifacts name with "c" in stead of "C".
As in mac os, the files system is case insensitive. so I can build it in command line without detecting this mistake.
In Eclipse it breaks, but it provides very bad error message. In the error list, it says "dependency problem", but the name of dependency is empty. It also can't identify which line in the POM causes the problem.
When try to open "Effective POM" in POM viewer, it will show project read error. In the pop up error dialog box, it will show:
Could not read maven project
java.nio.channels.OverlappingFileLockException
All the messages are useless and misleading.
I finally detected this problem by submit to Jenkins CI after wasted hours of time.
I did maven clean install and the errors were gone
I faced the same issue of "Project read error" while clicking on "Dependency Hierarchy" tab. In my project I had a parent pom and child pom.
Parent pom had a property <appVersion>4.5<appVersion> that was being used in child pom
<version>${appVersion}<version>.
I selected the main project, right click and choose run as maven clean. The console display showed warning that version is using expression but should be a constant. Replacing ${appVersion} with constant value of 4.5 fixed the issue.