[maven] How to force maven update?

I imported my already working project on another computer and it started to download dependencies.

Apparently my internet connection crashed and now I get the following:

    >Build errors for comics; org.apache.maven.lifecycle.LifecycleExecutionException:
    Failed to execute goal on project comicsTest: Could not resolve dependencies for project comicsTest:comicsTest:war:0.0.1-SNAPSHOT:
    The following artifacts could not be resolved:
    org.springframework:spring-context:jar:3.0.5.RELEASE,
    org.hibernate:hibernate-entitymanager:jar:3.6.0.Final,
    org.hibernate:hibernate-core:jar:3.6.0.Final,
    org.hibernate:hibernate-commons-annotations:jar:3.2.0.Final,
    org.aspectj:aspectjweaver:jar:1.6.8,
    commons-lang:commons-lang:jar:2.5,

    >mysql:mysql-connector-java:jar:5.1.13: Failure to transfer org.springframework:spring-context:jar:3.0.5.RELEASE from http://repo1.maven.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced.

    >Original error: Could not transfer artifact org.springframework:spring-context:jar:3.0.5.RELEASE from central (http://repo1.maven.org/maven2): No response received after 60000

How do I force maven to update?

For fixing this issue from Eclipse:

1) Add below dependency in Maven pom.xml and save the pom.xml file.

<!-- https://mvnrepository.com/artifact/com.thoughtworks.xstream/xstream -->
<dependency>
    <groupId>com.thoughtworks.xstream</groupId>
    <artifactId>xstream</artifactId>
    <version>1.3.1</version>
</dependency>

2) Go to project >> Maven >> Update Project

select the project and click OK.

3) Optional step, if it's not resolved till step 2 then do below step after doing step-1

Go to project >> Maven >> Update Project >> check in the checkbox 'Force Update of Snapshots/Releases'

select the project and click OK.

I had the same error and running mvn install -U and then running mvn install worked for me.

You can do effectively from Eclipse IDE. Of course if you are using it.

Project_Name->Maven->Update Project Configuration->Force Update of Snapshots/Releases

What maven does is, it downloads all your project's dependencies into your local repo (.m2 folder). Because of the internet causing issues with your local repo, you project is facing problems. I am not sure if this will surely help you or not but you can try deleting all the files within the repository folder inside the .m2 folder. Since there would be nothing in the local repo, maven would be forced to download the dependencies again, thus forcing an update. Generally, the .m2 folder is located at c:users:[username]:.m2

If you are using eclipse IDE then :

• Select Project.

• Press alt+F5, window for Update Maven Project will pop up.

• Check - Force Update of Snapshots/releases and click OK.

If Using Intellij IDE

• go to settings/Maven
• check Always update snapshots

mvn clean install -U doesn't work. However mvn -U clean followed by mvn clean install does.

-U is used to force update maven Repo. Use

mvn -U clean install

Just in case someone wants only update project's snapshot dependencies and doesn't want to install artifact:

mvn dependency:resolve -U

Don't forget to reimport dependencies in your IDE. In IDEA you need to right click on pom file and choose Maven -> Reimport

-U seems to force update of all dependencies.

If you want to update a single dependency without clean or -U you could just remove it from your local repo and then build.

The example below if for updating slf4j-api 1.7.1-SNAPSHOT:

rm -rf ~/.m2/repository/org/slf4j/slf4j-api/1.7.1-SNAPSHOT
mvn compile

I ran into this recently and running the following fixed all the problems

mvn -fae install

If you're unsure what is inside your local repository, I recommend to fire a build with the option:

-Dmaven.repo.local=localrepo

That way you'll ensure to build in a cleanroom environment.

I've got the error in an other context. So my solution might be useful to others who stumple upon the question:

The problem: I've copied the local repository to another computer, which has no connection to a special repository. So maven tried to check the artifacts against the invalid repository.

My solution: Remove the _maven.repositories files.

This is one of the most annoying things about Maven. For me the following happens: If I add a dependency requesting more dependencies and more and more but have a slow connection, it seams to stop while downloading and timing out. While timing out all dependencies not yet fetched are marked with place holders in the .m2 cache and Maven will not (never) pick it up unless I remove the place holder entry from the cache (as other stated) by removing it.

So as far as I see it, Maven or more precise the Eclipse Maven plugin has a bug regarding this. Someone should report this.

Previous versions of maven did not force the check for missing releases when used -U with mvn clean install, only the snapshots, though newer version supports this.

For someone still struggling with previous version, following can be helpful-

On Windows:

cd %userprofile%\.m2\repository
for /r %i in (*.lastUpdated) do del %i

On Linux:

find ~/.m2  -name "*.lastUpdated" -exec grep -q "Could not transfer" {} \; -print -exec rm {} \;

Whenever maven can't download dependencies for any reason (connectivity/not exists etc), it will add the ".error=Could not transfer artifact" in dependency-name.lastUpdate file in respective folder under $home/.m2 directory. Removing these files will force maven to try fetching the dependencies again.

All the answers here didn't work for me. I used the hammer method:

find ~/.m2/ -name "*.lastUpdated" | xargs rm

That fixed the problem :-)

I used the IntelliJ IDE and I had a similar problem and to solve I clicked in "Generate Sources and Update Folders for All Projects" in Maven tab.

If your local repository is somehow mucked up for release jars as opposed to snapshots (-U and --update-snapshots only update snapshots), you can purge the local repo using the following:

 mvn dependency:purge-local-repository

You probably then want to clean and install again:

 mvn dependency:purge-local-repository clean install

Lots more info available at https://maven.apache.org/plugins/maven-dependency-plugin/examples/purging-local-repository.html

I tried all the answers here but nothing seemed to work. Restarted my computer first then ran mvn clean install -U. That solved my problem.

I've got the same error with android-maps-utils dependency. Using aar type package in dependency section solve my problem. By default type is jar so It might be checked what type of dependency in repository is downloaded.

It's important to add that the main difference of running mvn with -U and without -U is that -U will override your local SNAPSHOT jars with remote SNAPSHOT jars.

Local SNAPSHOT jars created from local mvn install in cases where you have other modules of your proj that generate jars.

We can force to get latest update of release and snapshot repository with below command :

mvn --update-snapshots clean install

You need to check your settings.xml file under <maven_home>/conf directory.

I had this problem for a different reason. I went to the maven repository https://mvnrepository.com looking for the latest version of spring core, which at the time was 5.0.0.M3/ The repository showed me this entry for my pom.xml:

<!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>5.0.0.M3</version>
</dependency>

Naive fool that I am, I assumed that the comment was telling me that the jar is located in the default repository.

However, after a lot of head-banging, I saw a note just below the xml saying "Note: this artifact it located at Alfresco Public repository (https://artifacts.alfresco.com/nexus/content/repositories/public/)"

So the comment in the XML is completely misleading. The jar is located in another archive, which was why Maven couldn't find it!

In my case first I did was:

mvn clean install -U

Still it was showing same error then I closed project and again reopened it. Finally worked.