nexus：无法从/向 nexus 传输工件（http://localhost:8081/repository/maven-proxy-test/）

Question

I installed nexus repository manager 3 in my system. I configured maven2 proxy repository, when i tried to clean pom.xml file using 'mvn clean' command, I am getting below error.

[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------< com.sample.app:nexus-proxy-test >-------------------
[INFO] Building nexus-proxy-test 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
Downloading from nexus: http://localhost:8081/repository/maven-proxy-test/org/apache/maven/plugins/maven-clean-plugin/2.5/maven-clean-plugin-2.5.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  0.377 s
[INFO] Finished at: 2019-10-03T19:04:32+05:30
[INFO] ------------------------------------------------------------------------
[ERROR] Plugin org.apache.maven.plugins:maven-clean-plugin:2.5 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-clean-plugin:jar:2.5: Could not transfer artifact org.apache.maven.plugins:maven-clean-plugin:pom:2.5 from/to nexus (http://localhost:8081/repository/maven-proxy-test/): Not authorized -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginResolutionException

Error stack trace looks like below.

Caused by: org.apache.maven.wagon.authorization.AuthorizationException: Not authorized
    at org.apache.maven.wagon.providers.http.wagon.shared.AbstractHttpClientWagon.resourceExists (AbstractHttpClientWagon.java:838)
    at org.apache.maven.wagon.providers.http.wagon.shared.AbstractHttpClientWagon.resourceExists (AbstractHttpClientWagon.java:809)
    at org.eclipse.aether.transport.wagon.WagonTransporter$PeekTaskRunner.run (WagonTransporter.java:512)
    at org.eclipse.aether.transport.wagon.WagonTransporter.execute (WagonTransporter.java:435)
    at org.eclipse.aether.transport.wagon.WagonTransporter.peek (WagonTransporter.java:406)
    at org.eclipse.aether.connector.basic.BasicRepositoryConnector$PeekTaskRunner.runTask (BasicRepositoryConnector.java:390)
    at org.eclipse.aether.connector.basic.BasicRepositoryConnector$TaskRunner.run (BasicRepositoryConnector.java:364)
    at org.eclipse.aether.util.concurrency.RunnableErrorForwarder$1.run (RunnableErrorForwarder.java:75)
    at org.eclipse.aether.connector.basic.BasicRepositoryConnector$DirectExecutor.execute (BasicRepositoryConnector.java:644)
    at org.eclipse.aether.connector.basic.BasicRepositoryConnector.get (BasicRepositoryConnector.java:262)
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.performDownloads (DefaultArtifactResolver.java:499)
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve (DefaultArtifactResolver.java:401)
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifacts (DefaultArtifactResolver.java:229)
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifact (DefaultArtifactResolver.java:207)
    at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom (DefaultArtifactDescriptorReader.java:240)
    at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.readArtifactDescriptor (DefaultArtifactDescriptorReader.java:171)
    at org.eclipse.aether.internal.impl.DefaultRepositorySystem.readArtifactDescriptor (DefaultRepositorySystem.java:255)
    at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve (DefaultPluginDependenciesResolver.java:106)
    at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getPluginDescriptor (DefaultMavenPluginManager.java:182)
    at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getMojoDescriptor (DefaultMavenPluginManager.java:286)
    at org.apache.maven.plugin.DefaultBuildPluginManager.getMojoDescriptor (DefaultBuildPluginManager.java:244)
    at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.setupMojoExecution (DefaultLifecycleExecutionPlanCalculator.java:169)
    at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.setupMojoExecutions (DefaultLifecycleExecutionPlanCalculator.java:154)
    at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.calculateExecutionPlan (DefaultLifecycleExecutionPlanCalculator.java:130)
    at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.calculateExecutionPlan (DefaultLifecycleExecutionPlanCalculator.java:144)
    at org.apache.maven.lifecycle.internal.builder.BuilderCommon.resolveBuildPlan (BuilderCommon.java:97)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:111)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:81)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:56)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:128)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:305)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:192)
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:105)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:956)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:288)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:192)
    at sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke (Method.java:498)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:282)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:225)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:406)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:347)

Reference https://help.sonatype.com/learning/repository-manager-3/first-time-installation-and-setup/lesson-2%3A-proxy-and-hosted-maven-repositories

Answer 1

This is authorization issue. Open settings.xml file from folder where maven is installed and correct the user ID and password. It should solve your problem.

Jar is not getting downloaded because of incorrect passwords.

Answer 2

If you have made sure your settings.xml file has the correct user and password and it still doesn't work, make sure you are pointing to the right version of Maven. I had this error and it turned out my IDE was defaulting to a different version of Maven, one without a corrected settings.xml file.