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I'm working in eclipse and I have a problem that I can't import my personal java libraries.
I created the libraries and 'installed' them into my local maven repo (using mvn install). This created a subdirectory related to the 'version' name that was in the POM file from when I ran the command. Which seemed fine.
So in this directory there where the usual jar files and other stuff.
When I released this file I manually changed the name of the version in the POM. going from 0.0.1-SNAPSHOT to 0.0.1-RELEASE
This seems to have worked as I would have expected.
However I can't seem to find import the new release jar.
Using the maven repositories browser in eclipse I can see that the new artifact is in the 'local' repository.
I try to add the dependency in the following methods:
Select the main project -> Maven -> add dependency.
This adds the dependency details into the pom but with a type value detail of <type>pom.lastUpdated</type>
Select the project pom.xml file -> Maven -> add dependency.
This time the artifact for the 0.0.1-RELEASE is greyed out I can select it, but I guess nothing is actually happening.
The original 0.0.1-SNAPSHOT it selectable, and if I use this I do not have a <type> detail in the pom.
I don't understand why there is a difference in the RELEASE and SNAPSHOT artifacts, as they have both been generated in the same way, and clearly they are both visible in the browser, the contents of the directory on disk are the same. The file names and contents are identical with the exception of the word RELEASE or SNAPSHOT.
I know that I can simply add in the RELEASE jar to my build path, but this seems to be a ridiculous thing to have to do if I intend to use maven (or do I need to do this).
I don't want to use an external repo for storing my artifacts, and I'm not too keen to go to the trouble of installing nexus (or similar) on my local machine (just because I've had trouble with it in the past).
What am I missing so as I can get my maven project to see my local repository and all its artifacts.
Thanks in advance.
David
ps I've already tried things such as mvn dependency:purge-local-repository which definitely pulled in / updated all the local jar dependencies.
So I've managed to work around my problem.
As such this solution is ridiculous, and breaks all the purpose of maven.
So I found (from running maven from the cli) that there was an error in the parent of the project I was attempting to use.
The parent was missing a direct link to the scm plugin (version error).
Once I solved this problem, I then returned to the sub project, and got a lot of errors from missing stuff from the parent.
Essentially it was not 'seeing' all the log4j dependencies.
The solution (well non-solution really).
Add all the log4j dependencies to the sub project.
Edit in SCM and surefire test plugins (as it also started to fail the test code due to missing junit).
So this is great.
I have to define all my dependencies on log4j and in my sub / child project's pom.xml file.
I also need to define them all in my parent's pom.
As it then still refused to run tests in my new project (that used the above as a dependency), and refused to find log4j also. I then decided to add all of these as dependencies for my current project.
Great.
I thought the whole point of maven was I could define my dependency on log4j in my my logging library that I use (which is the dependency), and then it would 'automagically' pull in all the required from this dependency.
Clearly not.
As stated at the start. This is NOT AN ANSWER it is a crazy work around.
My logging library that I use should be able to define its own requirement on a specific log4j version (such as moving from log4j to log4j2), and then when I include this as a maven dependency any change to the required dependency should be seen automatically.
But No : I have to import the dependency on log4j in my other projects also. So now if I had updated my logging library from log4j to log4j2 I would need to go to all my project that use this library and update their pom's to ensure that I have the correct version of log4j.
Seems the whole point of maven has just been lost!
Can someone please tell me where I am going wrong!
David.
Forgive me asking following questions. I am totally lost in regards to maven+eclipse. I checked out someone's java project (maven built) from SVN to my local eclipse (kepler). When I click Windows > Preferences, I see Maven.
question 1)
Is this a maven plugin? When developers say maven in eclipse, are they referring to maven plugin? maven and maven plugin are two separate components?
question 2)
when I click on user settings, C:\Users\myName.m2\settings.xml is missing. Exact error message is "User settings file doesn't exist". Does it get created when you install maven plugin at first time?
question 3)
I found three folders may have to do with maven C:\workspace\maven_local_repo_artifactory directory, C:\maven_local_repo and C:\Users\myName.m2\respository but not sure how they get created and what is the relationship among them.
question 4)
Is it ok to remove current maven plugin from eclipse and re-install it then check out the java project from SVN? I think my maven or maven plugin settings are not correct in my local box.
1) Is this a maven plugin? When developers say maven in eclipse, are
they referring to maven plugin? maven and maven plugin are two
separate components?
Yes. This is the maven-plugin. maven-plugin uses the configurations of maven (%M2_HOME%/conf).
If you wanna work with maven, you need to install it on your machine. Then you can run maven commmands. In addition, if you want to invoke maven commands within eclipse (conveniently) - you can install the eclipse-plugin. "maven-plugin" is a plugin for eclipse, that lets you use maven within Eclipse conveniently.
2) when I click on user settings, C:\Users\myName.m2\settings.xml is
missing. Exact error message is "User settings file doesn't exist".
Does it get created when you install maven plugin at first time?
By default, the maven-plugin assumes that your settings.xml (which is the configuration file of maven) is in the path you have mentioned. However, there are cases (like in my case) where the config file is not there, but under %M2_HOME%/conf. you can update it in Eclipse, and the error will disappear.
3) I found three folders may have to do with maven
C:\workspace\maven_local_repo_artifactory directory,
C:\maven_local_repo and C:\Users\myName.m2\respository but not sure
how they get created and what is the relationship among them.
C:\Users\myName.m2\respository is the "local repository". If you learned a bit about how maven works, it holds a local repo on the local machine, and it keeps there all artifacts. It downloads them from the "repository" - if you have one in your company (Nexus, Artifactory, etc) or from Maven Central. However, this path is configurable by Maven's settings. So there might be that someone played with it and changed the path, and these other directories were created. You did not mention what resides inside these paths...
4) Is it ok to remove current maven plugin from eclipse and re-install
it then check out the java project from SVN? I think my maven or maven
plugin settings are not correct in my local box.
Sure it is OK. You may remove the plugin, and the source plus maven itself will not be deleted from your machine.
HTH.
Occasionally maven complains that a particular dependency, which is built and packaged locally, cannot be found in the local repository while building another project that has it as a dependency. We get an error like:
Failed to execute goal on project X: Could not resolve dependencies for project X: Failure to find Y in [archiva repository] was cached in the local repository, resolution will not be reattempted until the update interval of internal has elapsed or updates are forced ->
Where X is the project being built, and Y is the supposedly missing artifact. If you look in the local repository, the artifact is there. This artifact is never installed in our archiva repository, so the problem is purely based in the local repository.
We have tried various profiles in settings.xml, and of course "mvn -U". Neither do any good, nor should they because this artifact never goes any further than the local repository.
The only two things that seem to work are to wait a very long time until maven smartens up, or to completely delete the local repository. Presumably the waiting option is related to the aforementioned update interval.
We have experienced this problem with maven 3.0.2 and 3.0.3. We are using Archiva 1.0.3 (but again this shouldn't be a factor). Any help would be greatly appreciated.
The local Maven repo tracks where artifacts originally came from using a file named "_maven.repositories" in the artifact directory. After removing it, the build worked. This answer fixed the problem for me.
As the options here didn't work for me, I'm sharing how I solved it:
My project has a parent project (with its own pom.xml) that has many children modules, one of which (A) has a dependency to another child (B). When I tried mvn package in A, it didn't work because B could not be resolved.
Executing mvn install in the parent directory did the job. After that, I could do mvn package inside of A and only then it could find B.
Even in offline mode, maven will check remote repositories if there is a _remote.repositories marker for the dependency. If you need to operate in offline mode, you may need to delete these files.
The simple shell command below deletes these marker files. This is safe to do if you only use offline mode for the machine. I would NOT do this on a machine that needs to pull files down from the web.
I have used this strategy on a build server that is disconnected from the web. We have to transfer the repository to it, delete the marker files and then run in offline mode.
On Linux / Unix you can delete the remote repository marker files this way:
cd ~/.m2
find . -name "_remote.repositories" -type f -delete
Maven remembers when it didn't find something. The key is "resolution will not be reattempted until the update interval of internal has elapsed or updates are forced ->"
The quick solution is to delete your local "repository" subdirectory for the problem artifact - assuming you have fixed the problem with it. :)
mvn -U will force update from remote repository - again, assuming you have now populated remote with said artifact.
When this happened to me, it was because I'd blindly copied my settings.xml from a template and it still had the blank <localRepository/> element. This means that there's no local repository used when resolving dependencies (though your installed artifacts do still get put in the default location). When I'd replaced that with <localRepository>${user.home}\.m2\repository</localRepository> it started working.
For *nix, that would be <localRepository>${user.home}/.m2/repository</localRepository>, I suppose.
If you have <repositories/> defined in your pom.xml apparently your local repository is ignored.
Catch all. When solutions mentioned here don't work(happend in my case), simply delete all contents from '.m2' folder/directory, and do mvn clean install.
Even I faced this issue and solved it with 2 ways:
1) In your IDE select project and clean all projects then install all the maven dependencies by right clicking on project -> go to maven and Update project dependencies select all projects at once to install the same. Once this is done run the particular project
2) Else What you can do is check in the pom.xml for the dependencies for which you are getting error and "mvn clean install" those dependent project first and the install maven dependencies of the current project in which you facing issue. By this the dependencies of the local project will be build and jars will be created.
I run to the similar problem when my new project depend on oracle jdbc jar(which I have installed in my local repository and work well for other projects). I tried -U option ,deleting .lastupdate file or the whole directory and downlaod again,but it did not work. finally,I deleted the directory and installed it locally again,it works.
One of the errors I found around Maven is when I put my settings.xml file in the wrong directory. It has to be in .m2 folder under your user home dir. Check to make sure that is in the right place (along with settings-security.xml if you are using that).
I had DependencyResolutionException in Ubuntu Linux when I've installed local artifacts via a shell script. The solution was to delete the local artifacts and install them again "manually" - calling mvn install:install-file via terminal.
This happened because I had http instead of https in this:
<repository>
<id>jcenter</id>
<name>jcenter-bintray</name>
<url>https://jcenter.bintray.com</url>
</repository>
check if if your artifact Y have packaging set to "jar". If you have defined it as "war" by error or copy paste, it will show this strange "was cached in the local repository, resolution will not be reattempted until the update interval of internal has elapsed or updates are forced". I would expect something like "artifact Y is war, jar type expected".
In my case I needed project Y to be a WAR to be deployed through Tomcat, as well as it needed to be a JAR to be able to add it as a dependency in project X.
So in project Y's pom.xml, I added this plugin to create a JAR along with the WAR:
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>3.2.2</version>
<configuration>
<attachClasses>true</attachClasses>
<classesClassifier>classes</classesClassifier>
</configuration>
</plugin>
And while adding the dependency of project Y in project X's pom.xml, I had to add a classifier:
<dependency>
<groupId>groupId.of.project.Y</groupId>
<artifactId>project.Y</artifactId>
<version>1.0-SNAPSHOT</version>
<classifier>classes</classifier>
</dependency>
Note: when you build project Y, you will see 2 packagings in the target folder: project-Y.war and project-Y-classes.jar, so that's why while importing you are specifying the classes classifier to import the JAR and not the WAR.
Here is the long Solution to the problem
(Not Quick fix but will work if no other solution)
You're going to hate me for saying this but this is the truth about open source projects like eclipse. Because Open source is modular and allows you to build and develop a project in many ways with many tools such as maven, spring boot, options for xml or groovy, different eclipse updates & Etc. The problem is that eclipse allows you to run the project with missing maven builds because the IDE is smart enough to resolve dependencies using a remote_repository where it stores and catches the jar files that is not properly built on the project.
Because of this feature, You may actually have local build issues but just like DNS servers; if the solution is not found in the local directory, Eclipse will look for a solution in it's remote cached repository. When you delete the remote_repository and let Maven rebuild it a second time, The project may end up creating more errors and not build a second time or may possibly rebuild a cache that was missing. But that is unlikely.
So the long answer to fix your solution.
This is a project architecture issue!
SOLUTION:
What you need to do is look in to all your dependant project's pom.xml file and the maven dependencies folder in your local project and try to resolve all the missing dependency jars in your maven dependency folder. If you have a referenced library, I suggest moving those jars into your local project's maven dependency folder.
You have to work your way into solving every child project and then navigate into your root project and fix every single project by using Maven -> Build -> clean install (check off "skip tests" & "resolve workspace artifacts") until every project builds with a clean success.
most likely, when you force update your entire solution to all your projects, you will get a list of errors that you have the IDE auto-resolve. The auto-resolve will refer to a easy reference to fix the issue. But to deploy, you have to manually fix the project because Eclipse, Spring & Maven will work well together but there are maybe a few things they don't agree on. So, you have to play diplomat in those situations and figure it out.
That's the sad truth.
All said, I have a list of problems in my project. I have this issue. The war file generated has empty jar folders and the build is not clean without errors unless i force it. The WAR file generate will run a 404 error on tomcat server production and my angular application will throw a Cors-Error when executing the API.
All the errors on my front end project is artificial because the root of all issues is the WAR file generated. It did not generate with dependencies, the Main project did not execute in tomcat and tomcat server cannot run the spring initializer to deploy the cors-policy on the server to allow my angular application to communicate. But all in all, development environment works fine with no issues.
So that is my long ended solution for this thread.
I had the same error from a different cause: I'd created a starter POM containing our "good practice" dependencies, and built & installed it locally to test it. I could "see" it in the repo, but a project that used it got the above error. What I'd done was set the starter POM to pom, so there was no JAR. Maven was quite correct that it wasn't in Nexus -- but I wasn't expecting it to be, so the error was, ummm, unhelpful. Changing the starter POM to normal packaging & reinstalling fixed the issue.
In my case I had to add mavenLocal() in root level gradle dependency
mavenCentral()
mavenLocal()
so I have started using maven (with eclipse, and a local implementation of Sonatype) not that long ago, after getting through the initial pain I though everything was working.... apparently not !
I have my main project POM and all my child POM (I am using a 'flat' hierarchy, so all the sub projects are in the same folder as the parent POM). This seems to be working OK.
The sub project where all started and 'released' and tested before I started using Maven. I went to maven to solve my 'dependencies' problems... or rather make them more complicated in this instance.
Most of the 'Maven' stuff seems to work fine, but I can't resolve the dependencies of my 'sub projects' that have been released into my local ms/repository
Each day I start up eclipse and have the same problems, I have 'unable to resolve imports' on all my personal libraries, and all those that I use for them (such as Log4j, DDlUtils etc).
I thought the whole point of maven was that I would be able to put in an import declaration for a library, add the 'groupID' and other stuff to the child POM (or parent POM). And then have all the jars downloaded automagically when I run
mvn install
against the parent.
However each day I find I have to re-insert the build path to the libraries (internal and external) via the eclipse workspace and point them to the location of the libraries that I have downloaded as maven can't seem to find them anywhere.
Specifically with running Junit test, I can run them from the workspace (using run as junit) and they all pass fine. But if I try to run them with
mvn test
I get an message saying
java.lang;NoClassDefFoundError: org/junit/Assert
(and this is the same from within eclipse running the mvn test or from CLI)
with an error message in the output of
failed to execute goal org.apache.maven.plugins:maven.surfire-plugin:2.10:test
the POM and jar are in my M2_REPO, and I can find it when I search in sonatype, why can't maven find something that is part of its own system, exists in its repo.
but this obviously works just fine when I run via eclipse and point it to an independently downloaded junit library.
I don't know what extra info you may require, and I'm obviously missing something in either the m2e plugin, my maven install or in sonatype.
please help I'm begining to loose my hair!
and may soon be forced to return to an ant/ivy solution (but don't want to have to learn 'yet another tool' (in this case ivy).
Thanks in advance
David.
ps. i'm on a windows XP platform
edit...
can I get maven to build and release the jar and pom even though it thinks it is failing the tests (which is itn't as I'm doing them manually, and they pass just fine).
If I look in the 'effective POM' tab of my parent POM, the plugin stated above is not in there. I guess this means it is a maven config setting, but where do I add it, and why isn't it automatic when I run my first set of maven tests?
edit 2....
I just found this on the apache plugin comments page (http://maven.apache.org/plugins/maven-surefire-plugin/plugin-info.html), so I ran the code on the CLI, mvn surefire:help -Ddetail=true -Dgoal=test lots of stuff was downloaded, and now the tests run, but they fail within maven ? (remember they pass when run from eclipse using 'run as junit test)... so this is nearly a solution...
It sounds like you need make eclipse aware that the projects in question are Maven projects. You may have POMs set up for your projects, but for the m2e plugin to work you need to have either created the project as a Maven project ('New' -> 'Project...' -> 'Maven' -> 'Maven Project...'), or converted it into a Maven project by right clicking it then selecting 'Configure' -> 'Convert to Maven Project'. You will know that a project has been recognised as a Maven project because there will be a little blue 'M' in the top left of its icon, as shown in the screenshot below:
The main thing to note in the above picture is the 'Maven Dependencies' library. This is set up automatically by the m2e plugin. Whenever you add a dependency to a POM then the project's build path will be configured automatically, although sometimes you may need to force it to do so by right clicking the project and selecting 'Maven' -> 'Update Maven Configuration'. The important thing is that if everything is working then you should never have to update the build path yourself. Moveover, if you do update it yourself then any changes you make will likely get overwritten the next time you run the 'Update Maven Configuration' command.
Also worth noting from the picture is that the two dependencies 'mavenProjectTest' and 'primes' have folder icons next to them. This means that they have been picked up as workspace projects. For this to work the project must have 'workspace resolution' enabled, and the projects to be picked up need to be configured as m2e Maven projects as well.
You mention downloading external libraries. You shouldn't need to download any libraries yourself - by adding the right dependency declaration for an external library then Maven will download it from your configured remote repository (the first time anyway - afterwards it will then be able to get it from your local repository). By default, this is the Maven Central repository. To add an external library to your project just follow that link, enter the library in the search box, click on the version link for the version you require, then you will be taken to a page where there will be the dependency XML declaration that you can just copy and paste into your POM.
One more thing that may help is that you should make sure that your source folders follow the Maven default directory structure. That is, your test packages should be contained in a source folder called 'src/test/java', and the main project packages should go in 'src/main/java'. Otherwise Maven will not know where to find your source code. It is possible to configure a POM to tell Maven to expect your source code to be in different source folders, but it is highly recommended that you follow the standard Maven directory structure.
Since you have child modules, my suggestion would be to simplify things by creating a new Maven project from scratch that you can have a play around with. Once you are comfortable with that then try getting m2e to work for your multi-module project.
I remember your pain when first getting to grips with Maven, but it's great once you understand what it's doing and everything is working. I highly recommend reading through the free online book Maven: The Complete Reference - it helped me out a lot when I was getting started with Maven.
I have experienced the same messages and have found a working solution, thanks to one of my organization's Maven experts.
Here was my pom.xml that reproduces your error:
<dependencies>
<dependency>
<groupId>org.junit4</groupId>
<artifactId>org.junit4</artifactId>
<version>4.3.1</version>
</dependency>
</dependencies>
With it, I would get package org.junit does not exist messages and NoClassDefFoundError: org/junit/Assert. Similar to your experience, it worked great from Eclipse, green bars and all.
Here is the pom.xml that works:
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
I copied this from the example at the top of this Using JUnit page.
I'm trying to use this Sonatype Eclipse plugin for the first time to handle an existing (huge) software that I can build with maven form the command line.
I have configured the plugin to use my maven 2.2.1 installation instead of the built-in Maven 3.
In Eclipse I have 25 projects (loaded through the root pom.xml) and 4 of them have compilation errors; the maven console contains a lot of lines like this one:
Missing artifact commons-logging:commons-logging:jar:1.0.4:compile
I have all the jars in my repository and the M2_REPO classpath variable correctly defined. Why the plugin doesn't see all the jars?
The .classpath file of those projects simply references "MAVEN2_CLASSPATH_CONTAINER", there isn't a list of the jars.
The pom.xml in Eclipse shows an error on the first line for the missing jars but I can build from the command line!
Any idea? I need help! I will try to move to NetBeans if I don't solve this problem.
Thank you.
You may need to to tell Eclipse to force update:
Project -> Maven -> Update Maven Project
and then make sure you have selected:
Force Updates of Snapshots/Releases
this happens when mvn install copies some jar files into Maven repository and Eclipse had checked this repo BEFORE this jar has been copied there.
If Dependency management is enabled when the above problems occur in Eclipse you can Project > Maven > Disable Dependency Management and then \Project > Maven > Enable Dependency Management. This normally remove any dependency errors in the pom.xml.
Also do as #Nishant indicated in his answer above after the above steps to complete the projects dependencies.
right click on your project > Maven > Update Dependencies
then
right click on your project > Maven > Update Project configuration
Assuming you M2Eclipse plugin is installed correctly this should solve the issue. Also, check if there is an option right click project > Maven > Enable dependency Management select that.
Using Eclipse Kepler, the removing and re-adding of the maven nature fixed this same issue I was having. What this process actually did was modify the .settings/org.eclipse.m2e.core.prefs file, changing the line
resolveWorkspaceProjects=false
to
resolveWorkspaceProjects=true
So you could probably make this change manually if you had to.
Adding my 2c for future Googlers:
Whenever this problem shows up, I delete the corresponding folder from the m2 repository (on a mac it's on ~/.m2/repository) and build again from eclipse with clean install.
Works every single time.
Close eclipse IDE and open it again, this issue should be fixed.
Just to add yet another possible resolution, if you have a multi-project build with interdependencies, if you have a repository defined in a child project pom to resolve a specific dependency that only that project depends on and it is relying on a partent project for it's other resolutions it fails to see those dependencies in the child project (even though it works from the command line).
Move the repo definition to the parent pom.
The lack of jars in the build path suggests you haven't enabled Maven dependencies. Right-click on the project, select Maven, select "Enable Maven Dependency Management". This allows M2Eclipse to reference your POM.
I finally found a workaround. It is surely a bug in m2eclipse, however the problem disappeared when I added quartz-1.6.0.pom next to quartz-1.6.0.jar in .m2\repository\opensymphony\quartz\1.6.0\
The pom is not present at http://repo1.maven.org/maven2/opensymphony/quartz/1.6.0/ but you can extract it from quartz-1.6.0-bundle.jar linket at http://jira.opensymphony.com/browse/QUARTZ-482
It's a strange solution but it worked on the PCs of my collegues too.
None of the other suggestions worked, but the following steps worked for me (SpringSource Tool Suite 2.6.1):
Back up the contents of the local Maven repository
Delete the repository
Project > Maven > Update Dependencies
Replace anything not available in a public repository from the backup
If disabling and enabling project dependency management doesn't help (usualy it helps) you can modify .classpath file in your project and add a line:
<classpathentry kind="con" path="org.eclipse.m2e.MAVEN2_CLASSPATH_CONTAINER"/>
After eclipse restart dependencies should be added.
I had this same problem happened to me. On the CLI clean install, then on eclipse delete the dependency, paste it again and that did the trick.
Remove all the artifacts except the jar in maven local repository
Late answer: In my case I had multiple profiles in settings.xml. Building worked since the correct profile was selected in the Maven Build run config, but the editors showed errors because the profile was not selected via Project -> Maven -> Select Maven Profiles ...