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Could not calculate build plan: Plugin org.apache.maven [duplicate]

org.apache.maven.plugin.PluginResolutionException: Plugin org.apache.maven.plugins:maven-resources-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.5
at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve(DefaultPluginDependenciesResolver.java:129)
at org.eclipse.m2e.core.internal.project.registry.EclipsePluginDependenciesResolver.resolve(EclipsePluginDependenciesResolver.java:48)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getPluginDescriptor(DefaultMavenPluginManager.java:142)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getMojoDescriptor(DefaultMavenPluginManager.java:261)
at org.apache.maven.plugin.DefaultBuildPluginManager.getMojoDescriptor(DefaultBuildPluginManager.java:185)
at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.setupMojoExecution(DefaultLifecycleExecutionPlanCalculator.java:152)
at org.eclipse.m2e.core.internal.embedder.MavenImpl.setupMojoExecution(MavenImpl.java:386)
at org.eclipse.m2e.core.internal.project.registry.ProjectRegistryManager.setupMojoExecution(ProjectRegistryManager.java:865)
at org.eclipse.m2e.core.internal.project.registry.MavenProjectFacade.getMojoExecution(MavenProjectFacade.java:355)
at org.eclipse.m2e.core.project.configurator.AbstractCustomizableLifecycleMapping.getBuildParticipants(AbstractCustomizableLifecycleMapping.java:66)
at org.eclipse.m2e.core.project.configurator.AbstractLifecycleMapping.configure(AbstractLifecycleMapping.java:87)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:414)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:351)
at org.eclipse.m2e.core.ui.internal.UpdateMavenProjectJob.runInWorkspace(UpdateMavenProjectJob.java:74)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)
Caused by: org.sonatype.aether.resolution.ArtifactDescriptorException: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.5
at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom(DefaultArtifactDescriptorReader.java:296)
at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.readArtifactDescriptor(DefaultArtifactDescriptorReader.java:186)
at org.sonatype.aether.impl.internal.DefaultRepositorySystem.readArtifactDescriptor(DefaultRepositorySystem.java:279)
at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve(DefaultPluginDependenciesResolver.java:115)
I have read where many people were able to solve this by:
Deleting the folder from the local repository and letting it re-download it (this did not work)
By configuring eclipse to target your maven installation instead of the embedded one as described here (this did not work)
Could not calculate build plan :artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.4.3 is not available in the local repository
I am new to Maven so please excuse any of my ignorance.
This project is working on another machine, and just pulled it down from the repository on this one, with the same version of eclipse and m2e plugin installed. I have been fooling with this for over 10 hours now and it is driving me nuts (Maven has been nothing but headaches for me so far...)
EDITS
After looking closer I did notice that it is not downloading the .jar files into the local repository... I am not sure if that is something obvious...
I am not given the option to add Maven Dependencies to the build path.

I had the exact same problem.
[ERROR] Plugin org.apache.maven.plugins:maven-resources-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.5: Failure to find org.apache.maven.plugins:maven-resources-plugin:pom:2.5 in http://repo.maven.apache.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 -> [Help 1]
...
Had maven 3.0.5, eclipse Kepler with JBoss Dev Studio 7 installed. Computer sitting on internal network with proxy to the internet. Here's what I did.
0. Check the maven repositiory server is up
1. Check Proxy is set up and working
First I thought it was a proxy problem, I made sure that maven settings.xml contained the proxy settings (settings.xml can exist in two places one in MAVEN_HOME. The other in %userprofile%.m2\ with the later having higher precedence):
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>optional-proxyuser</username>
<password>optional-proxypass</password>
<host>proxy.host.net</host>
<port>80</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
and checked that the proxy is working by trying to telnet to it:
telnet [proxy] [port number]
2. Check not Eclipse Issue
ran 'mvn compile' at command line level outside of eclipse - same issue.
If 'mvn compile' worked. But it doesn't work using the maven plugin in eclipse, see Maven plugin not using eclipse's proxy settings
3. Check not Cache Issue
Deleted all contents in my local maven repository. (Default location: ~/.m2/repository) And then reran maven - same issue came up.
4. What worked for me
Automatically download & install missing plugin:
By declaring the missing plugin in the POM file build section for pluginManagement Maven will automatically retrieve the required plugin. In the POM file, add this code for the version of the plugin you require:
<build>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>2.7</version>
</plugin>
</plugins>
</pluginManagement>
</build>
Manually install missing plugin:
I went to http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-resources-plugin/2.5 and downloaded maven-resources-plugin-2.5.jar and maven-resources-plugin-2.5.pom . Copied it directly into the maven repository into the correct folder ( ~/.m2/repository/org/apache/maven/plugins/maven-resources-plugin/2.5) and reran 'mvn compile'. This solved the problem.
Edit1
Following this I had another two problem with 'mvn install':
The POM for org.apache.maven.plugins:maven-surefire-plugin:jar:2.10 is missing, no dependency information available
The POM for org.apache.maven.plugins:maven-install-plugin:jar:2.3.1 is missing, no dependency information available
I approached this problem the same way as above, downloading from http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-surefire-plugin/2.10 and http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-install-plugin/2.3.1

I had the exact same problem and since I read somewhere that the error was caused by a cached file, I fixed it by deleting all the files under the .m2 repository folder.
The next time I built the project I had to download all the dependencies again but it was worth it - 0 errors!!

Couple of things to try:
Doublecheck the location of the local artifact repo configured in your settings.xml file (at the following location {your home folder}/.m2/settings.xml). Are you sure the local repo is where you think it is? (Yes, a mistake I've made in the past...)
Remove entire contents of artifact repo on the new build machine (or at least anything related to Maven). You mentioned doing some artifact repo cleanup but I'm not sure what directory(ies) you removed. I've run into weird issues like these when a jar was corrupted.
Make sure you have enough disk space/quota for the local artifact repo. I have run into weird issues when I didn't have a large enough quota to hold all the artifacts, likely caused by partially downloaded jar files.
Try running with plain Maven on the command line; take Eclipse and m2e out of the equation. mvn -U dependency:resolve should do it. The -U forces Maven to download no matter what your repository update policies are. Add -X to get detailed debug logging.
Copy settings.xml from MAVEN_HOME\conf\ to USER_HOME.m2. Add proxies (if needed) in case you are behind a proxy server.

Follow easy steps to resolved the below issue:
Could not calculate build plan: Plugin org.apache.maven.plugins:maven-resources-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact description for org.apache.maven.plugins:maven-ar-plugin:ar:2.4 in eclipse
Solution:
Step1:
Step2:
Issue solved ☺

i faced the same issue while using eclipse kepler and maven version 3.2,
while building the project, it showed me the same error in eclipse
there are two versions (2.5 and 2.6) of plugin under
.m2/repository/org/apache/maven/plugins/maven-resources-plugin/
i removed 2.5 version then it worked for me

My problem was the location of the config file.
In eclipse settings (Windows->preferences->maven->User Settings) the default config file for maven points to C:\users\*yourUser*\.m2\settings.xml. If you unzip maven and install it in a folder of your choice the file will be inside *yourMavenInstallDir*/conf/, thus probably not where eclipse thinks (mine was not). If this is the case maven won't load correctly. You just need to set the "User Settings" path to point to the right file.

It appears that there can be a lot of different causes for this issue. I experienced it after installing a new version of Eclipse (Luna). Command-line maven worked fine, but Eclipse had build issues.
I use a Certificate Authority in my JRE. This is important because this provides my authentication when downloading Maven resources. Even though my project was pointing to the appropriate JRE inside of Eclipse - Eclipse was running using a different JRE (this is apparent looking at the Java process properties in Windows task manager). My solution was to add the following in my eclipse.ini
and explicitly define the JRE I want to use.
-vm
C:\Program Files\Java\jdk1.7.0_51\bin\javaw.exe

You should check Force Update Snapshots/Releases when updating project with maven.It worked for me :-).

his issue is happening due to change of protocol from http to https for central repository. please refer following link for more details. https://support.sonatype.com/hc/en-us/articles/360041287334-Central-501-HTTPS-Required
In order to fix the problem, copy following into your pom.ml file. This will set the repository url to use https.
<repositories>
<repository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
</pluginRepository>
</pluginRepositories>

Try to delete all dirs in /usr/share/maven-repo - of course then maven will die so you must re-install and try again. In my case re-install from maven ver.3. to maven2 with deleting all repositories helped.
I tried by deleting all from .m2 but that didn't help.

Some files where missing at your local repository. Usually under ${user.home}/.m2/repository/
Neets answer solves the problem. However if you dont want do download all the dependencies to your local repository again you could add the missing dependency to a project of yours and compile it.
Use the maven repository website to find the dependency.
In your case http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-resources-plugin/2.5 was missing.
Copy the listed XML to the pom.xml file of your project. In this case
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
<version>2.5</version>
</dependency>
Run mvn compile in the root folder of the pom.xml. Maven will download all missing dependencies. After the download you can remove the added dependency.
Now you should be able to import the maven project or update the project without the error.

What I found out is that while m2e is looking for v2.5 by default, my local repo has 2.6 and no 2.5.
Without going into investigation of how this came about
simply adding the dependency to pom solved the problem
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
<version>2.6</version>
</dependency>
This can be removed after running a build once

A more subtle reason for this could be a Settings.xml file which has a space in the first line before the doctype

Hopefully I'm not late for the party.
Encountered this using Eclipse Kepler and Maven 3.1.
The solution is to use a JDK and not a JRE for your Eclipse project. Make sure to try maven clean and test from eclipse just to download missing jars.

I had the same problem but with an other cause. The solution was to deactivate Avira Browser Protection (in german Browser-Schutz). I took the solusion from m2e cannot transfer metadata from nexus, but maven command line can. It can be activated again ones maven has the needed plugin.

Most people will tell you to check your proxy settings or delete and re-add artifacts, but I will stay away from that and give another suggestion in case that doesn't turn out to be your problem. It could be your mirror settings.
If you use maven at the office then there's a good chance maven is configured to look for your company's internal maven repository. If you're doing some work from home and you are not connected to the network this could be the problem. An obvious solution might be VPN to the office to get visibility to this repo. Another way around this is to add another mirror site to your /User/.m2/settings.xml file so if it fails to find it on your office network it will try public repo.
<mirror>
<id>Central</id>
<url>http://repo1.maven.org/maven2</url>
<mirrorOf>central</mirrorOf>
<!-- United States, St. Louis-->
</mirror>
For other maven repositories take a look here: http://docs.codehaus.org/display/MAVENUSER/Mirrors+Repositories

In my case I'm using an external maven installation with m2e. I've added my proxy settings to the external maven installation's settings.xml file. These settings haven't been used by m2e even after I've set the external maven installation as default maven installation.
To solve the problem I've configured the global maven settings file within eclipse to be the settings.xml file from my external maven installation.
Now eclipse can download the required artifacts.

After entering your proxy settings in settings.xml
<proxies>
<!-- proxy
| Specification for one proxy, to be used in connecting to the network.
| -->
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>DOMAIN\YOURID</username>
<password>123456</password>
<host>proxy.company.com</host>
<port>8080</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
</proxies>
Check whether the below tag is having the value false in settings.xml
<offline>false</offline>
This helped me.

In addition to what #JackDev replies, what also solved my problem was to
1) Install the jdk under directory with no spaces:
C:/Java
Instead of
C:/Program Files/Java
This is a known issue in Windows. I fixed JAVA_HOME as well
2) Install maven as in Java case, under C:/Maven. Fixed the M2_HOME accordingly.
3) I java 7 and java 8 on my laptop. So I defined the jvm using eclipse.ini. This is not a mandatory step if you don't have -vm entry in your eclipse.ini. I updated:
C:/Java/jdk1.7.0_79/jre/bin/javaw.exe
Instead of:
C:/Java/jdk1.7.0_79/bin/javaw.exe
Good luck

If you've configured a repository in your maven's settings.xml, check if you've access to it.
When I had this problem, there were enterprise repositories configured in settings.xml but I was out of the company.

JackDev's option 3 works for me after I changed the default repository to another folder.
Below is what I see after M2E plugin automatically download the maven-resources-plugin-2.6. Maybe this could give you some hint if you want to take the manual approach. The necessary files can be downloaded from here: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/

If you have a proxy, you also have to clear SOCKS in
Window > Preferences > Network Connections.

I was getting the same issue.
I just installed the m2e (Maven2Eclipse)plugin from below site:
http://www.eclipse.org/m2e/
Eclipse>Help>Install New Software>Available Software Sites>Add
Name: m2e (any name is OK)
Location:m2e - http://download.eclipse.org/technology/m2e/releases/
Under Install Window> Work with:
Select this new location and Add all the plugins that appear. Eclipse restart and it was running properly with no previous errors.

If your working at a company, they may be preventing you from downloading outside software and installing it. You may need to install the plugins manually or repoint to an internal mirror repository.

Try downloading a different version of maven.
I had the same problem with maven 3.5.2 , I solved my problem just downloading maven 3.0.4

Very old stuff.
Got it solved fixing the localRepository in settings.xml.
This file was copied from my other computer and the path of the .m2 repository wasn't the same.
<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
<localRepository>C:\Users\foo\.m2</localRepository>
</settings>

I could solve the issue with the following steps
Install Maven separately
https://www.mkyong.com/maven/how-to-install-maven-in-windows/
Set the external Maven installation in Eclipse
3. Set the proxy in settings.xml in Maven installation
(C:\path\apache-maven-3.6.0\conf)
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>optional-proxyuser</username>
<password>optional-proxypass</password>
<host>proxy.host.net</host>
<port>80</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
Update the Maven User Settings
Update Maven project

I have shifted my project to a different machine, copied all my maven libraries from old machine to new machine, did Right click on my project >> Maven >> Update Project. And then built my project. In addition to this, I have also done this one step which is shown in screenshot. And that's all it worked!!
Go to Window --> Preferences --> Maven --> User Setting, make sure you have these settings..
Also Right click on your project --> Properties --> Maven, and make sure you have the path here to maven repository..

I am facing the same issue and none of above works, like by updating the MVN also same error, by building is also same, entered details in settings.xml though even same issue.
After that again I tried and did something different which did not did before and it works.
Its simple, I clicked the force update while updating the Mvn project.
By right clicking on the pom file, there is option under Maven,
"Update Project" and it open up one popup to select update option.
PLEASE MAKE SURE FORCE UPDATE IS CHECKED, by default is unchecked. And
bingo, that works like charm!

To solve this issue I tried below method :
(I was working on eclipse IDE)
Go to location : C:\User\local.m2\setting.xml
Open setting.xml file in any editor.
Comment the proxy setting like I did(see below setting.xml file).
Then go to eclipse & perform Maven Update from :right clicking on your solution folder(Your Project)->select Maven->Update Project.
Hope it will work for you as like me.
<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
<!--
<proxies>
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>proxyuser</username>
<password>proxypass</password>
<host>proxy.host.net</host>
<port>80</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
</proxies>
-->
</settings>

Maven project - Could not calculate build plan [duplicate]

org.apache.maven.plugin.PluginResolutionException: Plugin org.apache.maven.plugins:maven-resources-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.5
at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve(DefaultPluginDependenciesResolver.java:129)
at org.eclipse.m2e.core.internal.project.registry.EclipsePluginDependenciesResolver.resolve(EclipsePluginDependenciesResolver.java:48)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getPluginDescriptor(DefaultMavenPluginManager.java:142)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getMojoDescriptor(DefaultMavenPluginManager.java:261)
at org.apache.maven.plugin.DefaultBuildPluginManager.getMojoDescriptor(DefaultBuildPluginManager.java:185)
at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.setupMojoExecution(DefaultLifecycleExecutionPlanCalculator.java:152)
at org.eclipse.m2e.core.internal.embedder.MavenImpl.setupMojoExecution(MavenImpl.java:386)
at org.eclipse.m2e.core.internal.project.registry.ProjectRegistryManager.setupMojoExecution(ProjectRegistryManager.java:865)
at org.eclipse.m2e.core.internal.project.registry.MavenProjectFacade.getMojoExecution(MavenProjectFacade.java:355)
at org.eclipse.m2e.core.project.configurator.AbstractCustomizableLifecycleMapping.getBuildParticipants(AbstractCustomizableLifecycleMapping.java:66)
at org.eclipse.m2e.core.project.configurator.AbstractLifecycleMapping.configure(AbstractLifecycleMapping.java:87)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:414)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:351)
at org.eclipse.m2e.core.ui.internal.UpdateMavenProjectJob.runInWorkspace(UpdateMavenProjectJob.java:74)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)
Caused by: org.sonatype.aether.resolution.ArtifactDescriptorException: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.5
at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom(DefaultArtifactDescriptorReader.java:296)
at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.readArtifactDescriptor(DefaultArtifactDescriptorReader.java:186)
at org.sonatype.aether.impl.internal.DefaultRepositorySystem.readArtifactDescriptor(DefaultRepositorySystem.java:279)
at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve(DefaultPluginDependenciesResolver.java:115)
I have read where many people were able to solve this by:
Deleting the folder from the local repository and letting it re-download it (this did not work)
By configuring eclipse to target your maven installation instead of the embedded one as described here (this did not work)
Could not calculate build plan :artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.4.3 is not available in the local repository
I am new to Maven so please excuse any of my ignorance.
This project is working on another machine, and just pulled it down from the repository on this one, with the same version of eclipse and m2e plugin installed. I have been fooling with this for over 10 hours now and it is driving me nuts (Maven has been nothing but headaches for me so far...)
EDITS
After looking closer I did notice that it is not downloading the .jar files into the local repository... I am not sure if that is something obvious...
I am not given the option to add Maven Dependencies to the build path.

I had the exact same problem.
[ERROR] Plugin org.apache.maven.plugins:maven-resources-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.5: Failure to find org.apache.maven.plugins:maven-resources-plugin:pom:2.5 in http://repo.maven.apache.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 -> [Help 1]
...
Had maven 3.0.5, eclipse Kepler with JBoss Dev Studio 7 installed. Computer sitting on internal network with proxy to the internet. Here's what I did.
0. Check the maven repositiory server is up
1. Check Proxy is set up and working
First I thought it was a proxy problem, I made sure that maven settings.xml contained the proxy settings (settings.xml can exist in two places one in MAVEN_HOME. The other in %userprofile%.m2\ with the later having higher precedence):
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>optional-proxyuser</username>
<password>optional-proxypass</password>
<host>proxy.host.net</host>
<port>80</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
and checked that the proxy is working by trying to telnet to it:
telnet [proxy] [port number]
2. Check not Eclipse Issue
ran 'mvn compile' at command line level outside of eclipse - same issue.
If 'mvn compile' worked. But it doesn't work using the maven plugin in eclipse, see Maven plugin not using eclipse's proxy settings
3. Check not Cache Issue
Deleted all contents in my local maven repository. (Default location: ~/.m2/repository) And then reran maven - same issue came up.
4. What worked for me
Automatically download & install missing plugin:
By declaring the missing plugin in the POM file build section for pluginManagement Maven will automatically retrieve the required plugin. In the POM file, add this code for the version of the plugin you require:
<build>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>2.7</version>
</plugin>
</plugins>
</pluginManagement>
</build>
Manually install missing plugin:
I went to http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-resources-plugin/2.5 and downloaded maven-resources-plugin-2.5.jar and maven-resources-plugin-2.5.pom . Copied it directly into the maven repository into the correct folder ( ~/.m2/repository/org/apache/maven/plugins/maven-resources-plugin/2.5) and reran 'mvn compile'. This solved the problem.
Edit1
Following this I had another two problem with 'mvn install':
The POM for org.apache.maven.plugins:maven-surefire-plugin:jar:2.10 is missing, no dependency information available
The POM for org.apache.maven.plugins:maven-install-plugin:jar:2.3.1 is missing, no dependency information available
I approached this problem the same way as above, downloading from http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-surefire-plugin/2.10 and http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-install-plugin/2.3.1

I had the exact same problem and since I read somewhere that the error was caused by a cached file, I fixed it by deleting all the files under the .m2 repository folder.
The next time I built the project I had to download all the dependencies again but it was worth it - 0 errors!!

Couple of things to try:
Doublecheck the location of the local artifact repo configured in your settings.xml file (at the following location {your home folder}/.m2/settings.xml). Are you sure the local repo is where you think it is? (Yes, a mistake I've made in the past...)
Remove entire contents of artifact repo on the new build machine (or at least anything related to Maven). You mentioned doing some artifact repo cleanup but I'm not sure what directory(ies) you removed. I've run into weird issues like these when a jar was corrupted.
Make sure you have enough disk space/quota for the local artifact repo. I have run into weird issues when I didn't have a large enough quota to hold all the artifacts, likely caused by partially downloaded jar files.
Try running with plain Maven on the command line; take Eclipse and m2e out of the equation. mvn -U dependency:resolve should do it. The -U forces Maven to download no matter what your repository update policies are. Add -X to get detailed debug logging.
Copy settings.xml from MAVEN_HOME\conf\ to USER_HOME.m2. Add proxies (if needed) in case you are behind a proxy server.

Follow easy steps to resolved the below issue:
Could not calculate build plan: Plugin org.apache.maven.plugins:maven-resources-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact description for org.apache.maven.plugins:maven-ar-plugin:ar:2.4 in eclipse
Solution:
Step1:
Step2:
Issue solved ☺

i faced the same issue while using eclipse kepler and maven version 3.2,
while building the project, it showed me the same error in eclipse
there are two versions (2.5 and 2.6) of plugin under
.m2/repository/org/apache/maven/plugins/maven-resources-plugin/
i removed 2.5 version then it worked for me

My problem was the location of the config file.
In eclipse settings (Windows->preferences->maven->User Settings) the default config file for maven points to C:\users\*yourUser*\.m2\settings.xml. If you unzip maven and install it in a folder of your choice the file will be inside *yourMavenInstallDir*/conf/, thus probably not where eclipse thinks (mine was not). If this is the case maven won't load correctly. You just need to set the "User Settings" path to point to the right file.

It appears that there can be a lot of different causes for this issue. I experienced it after installing a new version of Eclipse (Luna). Command-line maven worked fine, but Eclipse had build issues.
I use a Certificate Authority in my JRE. This is important because this provides my authentication when downloading Maven resources. Even though my project was pointing to the appropriate JRE inside of Eclipse - Eclipse was running using a different JRE (this is apparent looking at the Java process properties in Windows task manager). My solution was to add the following in my eclipse.ini
and explicitly define the JRE I want to use.
-vm
C:\Program Files\Java\jdk1.7.0_51\bin\javaw.exe

You should check Force Update Snapshots/Releases when updating project with maven.It worked for me :-).

his issue is happening due to change of protocol from http to https for central repository. please refer following link for more details. https://support.sonatype.com/hc/en-us/articles/360041287334-Central-501-HTTPS-Required
In order to fix the problem, copy following into your pom.ml file. This will set the repository url to use https.
<repositories>
<repository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
</pluginRepository>
</pluginRepositories>

Try to delete all dirs in /usr/share/maven-repo - of course then maven will die so you must re-install and try again. In my case re-install from maven ver.3. to maven2 with deleting all repositories helped.
I tried by deleting all from .m2 but that didn't help.

Some files where missing at your local repository. Usually under ${user.home}/.m2/repository/
Neets answer solves the problem. However if you dont want do download all the dependencies to your local repository again you could add the missing dependency to a project of yours and compile it.
Use the maven repository website to find the dependency.
In your case http://mvnrepository.com/artifact/org.apache.maven.plugins/maven-resources-plugin/2.5 was missing.
Copy the listed XML to the pom.xml file of your project. In this case
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
<version>2.5</version>
</dependency>
Run mvn compile in the root folder of the pom.xml. Maven will download all missing dependencies. After the download you can remove the added dependency.
Now you should be able to import the maven project or update the project without the error.

What I found out is that while m2e is looking for v2.5 by default, my local repo has 2.6 and no 2.5.
Without going into investigation of how this came about
simply adding the dependency to pom solved the problem
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
<version>2.6</version>
</dependency>
This can be removed after running a build once

A more subtle reason for this could be a Settings.xml file which has a space in the first line before the doctype

Hopefully I'm not late for the party.
Encountered this using Eclipse Kepler and Maven 3.1.
The solution is to use a JDK and not a JRE for your Eclipse project. Make sure to try maven clean and test from eclipse just to download missing jars.

I had the same problem but with an other cause. The solution was to deactivate Avira Browser Protection (in german Browser-Schutz). I took the solusion from m2e cannot transfer metadata from nexus, but maven command line can. It can be activated again ones maven has the needed plugin.

Most people will tell you to check your proxy settings or delete and re-add artifacts, but I will stay away from that and give another suggestion in case that doesn't turn out to be your problem. It could be your mirror settings.
If you use maven at the office then there's a good chance maven is configured to look for your company's internal maven repository. If you're doing some work from home and you are not connected to the network this could be the problem. An obvious solution might be VPN to the office to get visibility to this repo. Another way around this is to add another mirror site to your /User/.m2/settings.xml file so if it fails to find it on your office network it will try public repo.
<mirror>
<id>Central</id>
<url>http://repo1.maven.org/maven2</url>
<mirrorOf>central</mirrorOf>
<!-- United States, St. Louis-->
</mirror>
For other maven repositories take a look here: http://docs.codehaus.org/display/MAVENUSER/Mirrors+Repositories

In my case I'm using an external maven installation with m2e. I've added my proxy settings to the external maven installation's settings.xml file. These settings haven't been used by m2e even after I've set the external maven installation as default maven installation.
To solve the problem I've configured the global maven settings file within eclipse to be the settings.xml file from my external maven installation.
Now eclipse can download the required artifacts.

After entering your proxy settings in settings.xml
<proxies>
<!-- proxy
| Specification for one proxy, to be used in connecting to the network.
| -->
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>DOMAIN\YOURID</username>
<password>123456</password>
<host>proxy.company.com</host>
<port>8080</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
</proxies>
Check whether the below tag is having the value false in settings.xml
<offline>false</offline>
This helped me.

In addition to what #JackDev replies, what also solved my problem was to
1) Install the jdk under directory with no spaces:
C:/Java
Instead of
C:/Program Files/Java
This is a known issue in Windows. I fixed JAVA_HOME as well
2) Install maven as in Java case, under C:/Maven. Fixed the M2_HOME accordingly.
3) I java 7 and java 8 on my laptop. So I defined the jvm using eclipse.ini. This is not a mandatory step if you don't have -vm entry in your eclipse.ini. I updated:
C:/Java/jdk1.7.0_79/jre/bin/javaw.exe
Instead of:
C:/Java/jdk1.7.0_79/bin/javaw.exe
Good luck

If you've configured a repository in your maven's settings.xml, check if you've access to it.
When I had this problem, there were enterprise repositories configured in settings.xml but I was out of the company.

JackDev's option 3 works for me after I changed the default repository to another folder.
Below is what I see after M2E plugin automatically download the maven-resources-plugin-2.6. Maybe this could give you some hint if you want to take the manual approach. The necessary files can be downloaded from here: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/

If you have a proxy, you also have to clear SOCKS in
Window > Preferences > Network Connections.

I was getting the same issue.
I just installed the m2e (Maven2Eclipse)plugin from below site:
http://www.eclipse.org/m2e/
Eclipse>Help>Install New Software>Available Software Sites>Add
Name: m2e (any name is OK)
Location:m2e - http://download.eclipse.org/technology/m2e/releases/
Under Install Window> Work with:
Select this new location and Add all the plugins that appear. Eclipse restart and it was running properly with no previous errors.

If your working at a company, they may be preventing you from downloading outside software and installing it. You may need to install the plugins manually or repoint to an internal mirror repository.

Try downloading a different version of maven.
I had the same problem with maven 3.5.2 , I solved my problem just downloading maven 3.0.4

Very old stuff.
Got it solved fixing the localRepository in settings.xml.
This file was copied from my other computer and the path of the .m2 repository wasn't the same.
<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
<localRepository>C:\Users\foo\.m2</localRepository>
</settings>

I could solve the issue with the following steps
Install Maven separately
https://www.mkyong.com/maven/how-to-install-maven-in-windows/
Set the external Maven installation in Eclipse
3. Set the proxy in settings.xml in Maven installation
(C:\path\apache-maven-3.6.0\conf)
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>optional-proxyuser</username>
<password>optional-proxypass</password>
<host>proxy.host.net</host>
<port>80</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
Update the Maven User Settings
Update Maven project

I have shifted my project to a different machine, copied all my maven libraries from old machine to new machine, did Right click on my project >> Maven >> Update Project. And then built my project. In addition to this, I have also done this one step which is shown in screenshot. And that's all it worked!!
Go to Window --> Preferences --> Maven --> User Setting, make sure you have these settings..
Also Right click on your project --> Properties --> Maven, and make sure you have the path here to maven repository..

I am facing the same issue and none of above works, like by updating the MVN also same error, by building is also same, entered details in settings.xml though even same issue.
After that again I tried and did something different which did not did before and it works.
Its simple, I clicked the force update while updating the Mvn project.
By right clicking on the pom file, there is option under Maven,
"Update Project" and it open up one popup to select update option.
PLEASE MAKE SURE FORCE UPDATE IS CHECKED, by default is unchecked. And
bingo, that works like charm!

To solve this issue I tried below method :
(I was working on eclipse IDE)
Go to location : C:\User\local.m2\setting.xml
Open setting.xml file in any editor.
Comment the proxy setting like I did(see below setting.xml file).
Then go to eclipse & perform Maven Update from :right clicking on your solution folder(Your Project)->select Maven->Update Project.
Hope it will work for you as like me.
<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
<!--
<proxies>
<proxy>
<id>optional</id>
<active>true</active>
<protocol>http</protocol>
<username>proxyuser</username>
<password>proxypass</password>
<host>proxy.host.net</host>
<port>80</port>
<nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>
</proxies>
-->
</settings>

NanoHTTPD Example Build Error

This question is really, really stupid as I have no experience with Maven.
I was interested in NanoHTTPD as an embedded web server in my project, but upon downloading the source and testing it out, I get the following error:
Failed to execute goal on project nanohttpd-samples: Could not resolve dependencies for project fi.iki.elonen:nanohttpd-samples:jar:2.0.2: The following artifacts could not be resolved: fi.iki.elonen:nanohttpd:jar:2.0.2, fi.iki.elonen:nanohttpd-webserver:jar:2.0.2: Failure to find fi.iki.elonen:nanohttpd:jar:2.0.2 in http://repo.maven.apache.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 -> [Help 1]
I tried the -e flag and netbeans spat out a tonne more errors related to Maven, which none made sense.
I also tried putting together one that did not involve Maven myself, which it didn't work.
I Googled for an hour and absolutely no answers are avail. Results are <10 and none are related to nanohttpd.
I know Maven is similar to Ant, but I have no idea how it works.
Anyway,
NanoHTTPD > https://github.com/NanoHttpd/nanohttpd
I am using netbeans, with JDK 7 downloaded today on this new linux box.
Help is appreciated. Below is the error reproduced on Fedora Netbeans, Stock JDK7 + NB bundle.
Full resolution : http://img10.imageshack.us/img10/2061/screenshot0608201310360.png
Thank you!

I notice that there are 2 failing tests in the main (core) package of NanoHttpd. I've fixed those and the build runs cleanly on a Ubuntu VM.
I would suggest pulling the latest from master and trying the build again, should all be fixed.
Oh, and thanks ... without you running into this issue, I might not have known about build errors when running on a a linux platform!

You can try multiple things:
1: Try deleting the corresponding failed to download artifact directory
in your local repo. Next time I run the maven command the artifact
download is triggered again. Therefore I'd say it's a client side
setting. Local repo path:
Unix/Mac OS X – ~/.m2
Windows – C:\Documents and Settings{your-username}.m2
2: As specified in the settings reference, I guess what you need is to
change the default value of updatePolicy in Maven Settings, which is
daily. I am not sure if this applies to a failed download though.
Also, always is ok for snapshots not for releases.
<profiles>
<profile>
...
<repositories>
<repository>
<id>myRepo</id>
<name>My Repository</name>
<releases>
<enabled>false</enabled>
<updatePolicy>always</updatePolicy>
<checksumPolicy>warn</checksumPolicy>
</releases>
</repository>
</repositories>
...
</profile>
</profiles>
...
</settings>
3: Use the -U in the build goal
4: Make sure you are using proper maven version Maven3/Maven2

Please help get started with creating a simple project using eclipse, spring, maven

I installed maven and configured based on their 5 minute tutorial
Created a eclipse project using Maven
Installed Maven Integration for eclipse by going to eclipse market place
Added dependencies (spring, log4j) to pom.xml by getting the xml snippet from mvnrepository.com
right click on pom.xml and run as Maven Install.
I was not able to use the new jar files immediately, had to do mvn install several times and finally all the jar files are showed up in the project.
what could be the problem? Is it not updating the class path correctly?
My questions are:
Are my steps above correct?
I see all the dependent jar files in the main folder. I want to place these jar files under lib folder. How do i do that?
How can i add external jar file to the repository, these are not in mvnrepository
How do i generate ear file to be deployed to weblogic?
Edit: Attached the screenshot of the repository
Edit2: i picked the wrong project type. Once i picked webapp archetype, it puts all dependencies in "Maven Dependencies". This is related to my second question.

For your question 3 : You can add any public maven repositories in to your pom file which contains your required jar files.
http://forum.springsource.org/showthread.php?63612-Maven-repository-location
or else if you have that jar file in your local machine you can manually install it into maven repository.
mvn install:install-file -Dfile=<path-to-file> -DgroupId=group-id
-DartifactId=artifact-id -Dversion=version -Dpackaging=packaging
As per the Guide to installing 3rd party JARs.
For your 2nd question you can use:
http://maven.apache.org/plugins/maven-dependency-plugin/

If you are using m2eclipse, be sure to right click on the project, select Maven and then "Update project configuration". That should be enough. I assume that you added the Maven project nature already.

After you create project use can use this command
mvn eclipse:eclipse -Dwtpversion=2.0
then install m2eclipse from eclipse marketplace. What I am doing generally is right click eclipse, import/import new maven project and choose my new maven project. Afer import if you dont see your jar folder under Libraries node of project tree, then right click build path/libraries/add class path and choose related folder.
If your library not available in current repository you can use another external repository with below tag: (jboss and java.net repos are very common)
<repositories>
<repository>
<id>java.net2</id>
<url>https://repository.jboss.org/nexus.</url>
<layout>default</layout>
<releases>
<enabled>true</enabled>
<updatePolicy>never</updatePolicy>
<checksumPolicy>warn</checksumPolicy>
</releases>
<snapshots>
<enabled>false</enabled>
<updatePolicy>always</updatePolicy>
<checksumPolicy>warn</checksumPolicy>
</snapshots>
</repository>
</repositories>

How do I configure Maven for offline development?

Does maven require a connection to the internet at some point to be able to use it? Meaning specifically getting the internal maven plugins for compiling, cleaning, packaging, etc?

You can run Maven in "offline" mode using the -o or -offline option (e.g. mvn -o install). Of course any artifacts not available in your local repository will fail. Maven is not predicated on distributed repositories, but they certainly make things more seamless. It's for this reason that many shops use internal mirrors that are incrementally synced with the central repos.
In addition, the mvn dependency:go-offline can be used to ensure you have all of your dependencies installed locally before you begin to work offline.

If you have a PC with internet access in your LAN, you should install a local Maven repository.
I recommend Artifactory Open Source. This is what we use in our organization, it is really easy to setup.
Artifactory acts as a proxy between your build tool (Maven, Ant, Ivy, Gradle etc.) and the outside world.
It caches remote artifacts so that you don’t have to download them over and over again.
It blocks unwanted (and sometimes security-sensitive) external requests for internal artifacts and controls how and where artifacts are deployed, and by whom.
After setting up Artifactory you just need to change Maven's settings.xml in the development machines:
<?xml version="1.0" encoding="UTF-8"?>
<settings xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd" xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<mirrors>
<mirror>
<mirrorOf>*</mirrorOf>
<name>repo</name>
<url>http://maven.yourorganization.com:8081/artifactory/repo</url>
<id>repo</id>
</mirror>
</mirrors>
<profiles>
<profile>
<repositories>
<repository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>central</id>
<name>libs-release</name>
<url>http://maven.yourorganization.com:8081/artifactory/libs-release</url>
</repository>
<repository>
<snapshots />
<id>snapshots</id>
<name>libs-snapshot</name>
<url>http://maven.yourorganization.com:8081/artifactory/libs-snapshot</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>central</id>
<name>plugins-release</name>
<url>http://maven.yourorganization.com:8081/artifactory/plugins-release</url>
</pluginRepository>
<pluginRepository>
<snapshots />
<id>snapshots</id>
<name>plugins-snapshot</name>
<url>http://maven.yourorganization.com:8081/artifactory/plugins-snapshot</url>
</pluginRepository>
</pluginRepositories>
<id>artifactory</id>
</profile>
</profiles>
<activeProfiles>
<activeProfile>artifactory</activeProfile>
</activeProfiles>
</settings>
We used this solution because we had problems with internet access in our development machines and some artifacts downloaded corrupted files or didn't download at all. We haven't had problems since.

You have two options for this:
1.) make changes in the settings.xml add this in first tag
<localRepository>C:/Users/admin/.m2/repository</localRepository>
2.) use the -o tag for offline command.
mvn -o clean install -DskipTests=true
mvn -o jetty:run

Maven needs the dependencies in your local repository. The easiest way to get them is with internet access (or harder using other solutions provided here).
So assumed that you can get temporarily internet access you can prepare to go offline using the maven-dependency-plugin with its dependency:go-offline goal. This will download all your project dependencies to your local repository (of course changes in the dependencies / plugins will require new internet / central repository access).

Sadly dependency:go-offline hasn't worked for me as it didn't cached
everything, ie. POMs files and other implicitly mention dependencies.
The workaround has been to specify a local repository location, either within settings.xml file with <localRepository>...</localRepository> or by running mvn with -Dmaven.repo.local=... parameter.
After initial project build, all necessary artifacts should be cached, and then you can reference repository location the same ways, while running Maven build in offline mode (mvn -o ...).

Before going offline you have to make sure that everything is in your local repo, which is required while working offline. Running "mvn dependency:go-offline" for the project(s)/pom(s), you intend to work on, will reduce the efforts to achieve this.
But it´s usually not the whole story, because dependency:go-offline will only download the "bare build" plugins (go-offline / resolve-plugins does not resolve all plugin dependencies). So you have to find a way to download deploy / test / site plugins (and maybe others) and their dependencies into your repo.
Furthermore dependency:go-offline does not download the pom´s artifact itself, so you have to dependency:copy it if required.
Sometimes - as MaDa wrote - you do not know, what you will need, while being offline, which makes it pretty impossible to have a "sufficient" repo.
Anyway having a properly filled repo you only have to add "<offline>true</offline>" to Maven´s settings.xml to go offline.
Do not change the Maven profile (id) you used to fill your repo, while being offline. Maven recognizes the downloaded artifacts in its metadata with an "identity", which is bound to the profile id.

If you're using IntelliJ, you can simply go to Preferences -> Build, Execution, Deployment -> Build Tools -> Maven and check/uncheck Work offline.

Does this work for you?
http://jojovedder.blogspot.com/2009/04/running-maven-offline-using-local.html
Don't forget to add it to your plugin repository and point the url to wherever your repository is.
<repositories>
<repository>
<id>local</id>
<url>file://D:\mavenrepo</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>local</id>
<url>file://D:\mavenrepo</url>
</pluginRepository>
</pluginRepositories>
If not, you may need to run a local server, e.g. apache, on your machines.

(source: jfrog.com)
or
Just use Maven repository servers like Sonatype Nexus http://www.sonatype.org/nexus/ or JFrog Artifactory https://www.jfrog.com/artifactory/.
After one developer builds a project, build by next developers or Jenkins CI will not require Internet access.
Maven repository server also can have proxies configured to access Maven Central (or more needed public repositories), and they can have cynch'ed list of artifacts in remote repositories.

My experience shows that the -o option doesn't work properly and that the go-offline goal is far from sufficient to allow a full offline build:
The solution I could validate includes the use of the --legacy-local-repository maven option rather than the -o (offline) one and
the use of the local repository in place of the distribution repository
In addition, I had to copy every maven-metadata-maven2_central.xml files of the local-repo into the maven-metadata.xml form expected by maven.
See the solution I found here.

A new plugin has appeared to fix shortcomings of mvn dependency:go-offline:
https://github.com/qaware/go-offline-maven-plugin
Add it in your pom, then run mvn -T1C de.qaware.maven:go-offline-maven-plugin:resolve-dependencies. Once you've setup all dynamic dependencies, maven won't try to download anything again (until you update versions).

Answering your question directly: it does not require an internet connection, but access to a repository, on LAN or local disk (use hints from other people who posted here).
If your project is not in a mature phase, that means when POMs are changed quite often, offline mode will be very impractical, as you'll have to update your repository quite often, too. Unless you can get a copy of a repository that has everything you need, but how would you know? Usually you start a repository from scratch and it gets cloned gradually during development (on a computer connected to another repository). A copy of the repo1.maven.org public repository weighs hundreds of gigabytes, so I wouldn't recommend brute force, either.

Here's a clear, straightforward way to cache Maven dependencies for offline development (based on #luka5z and others' comments):
While you have internet access, cache dependencies locally:
mvn -Dmaven.repo.local=dependencies install
Disconnect from the internet, verify that offline mode compilation succeeds:
mvn clean
mvn -o -Dmaven.repo.local=dependencies package
Continue developing offline as long as needed.

In preparation before working offline just run
mvn dependency:go-offline

<offline> false </offline>
<localRepository>${user.home}/.m2/repository</localRepository>
to
<offline> true <offline>
<localRepository>${user.home}/.m2/repository</localRepository>
Change the offline tag from false to true .
will download from repo online