"Non-resolvable parent POM: Could not transfer artifact" when trying to refer to a parent pom from a child pom with ${parent.groupid}

Question

I'm following a tutorial for maven. I have a very simple project with a couple of modules inside. On the module pom I want to reference the main proyect pom version and group through ${parent.groupid} and ${parent.version} so if I change any of those I won't have to hunt the down in the child poms and change them but I'm getting the Non-resolvable parent POM: Could not transfer artifact error

I've read several "Non-resolvable parent POM:" questions here at stackoverflow but nothing that I've read has helped.

My directory structure is as follows:

tutorial_maven(dir)
 --> pom.xml(file)
 --> tutorial_maven_jar(dir)
     --> pom.xml(file)

I'm getting the following Error:

Apache Maven 3.0.4 (r1232337; 2012-01-17 03:44:56-0500)
Maven home: C:\Program Files (x86)\apache-maven-3.0.4
Java version: 1.7.0_09, vendor: Oracle Corporation
Java home: C:\Program Files\Java\jdk1.7.0_09\jre
Default locale: es_EC, platform encoding: UTF-8
OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
[INFO] Error stacktraces are turned on.
[DEBUG] Reading global settings from C:\Program Files (x86)\apache-maven-3.0.4\conf\settings.xml
[DEBUG] Reading user settings from C:\Users\fureta.DESARROLLO03\.m2\settings.xml
[WARNING] Command line option -npr is deprecated and will be removed in future Maven versions.
[DEBUG] Using local repository at C:\Users\fureta.DESARROLLO03\.m2\repository
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for C:\Users\fureta.DESARROLLO03\.m2\repository
[INFO] Scanning for projects...
[DEBUG] Using connector WagonRepositoryConnector with priority 0 for http://repo.maven.apache.org/maven2
Downloading: http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tutorial_maven-${parent.version}.pom
[DEBUG] Writing resolution tracking file C:\Users\fureta.DESARROLLO03\.m2\repository\${parent\groupId}\tutorial_maven\${parent.version}\tutorial_maven-${parent.version}.pom.lastUpdated
[DEBUG] Extension realms for project org.felipe:tutorial_maven:pom:1.0-SNAPSHOT: (none)
[DEBUG] Looking up lifecyle mappings for packaging pom from ClassRealm[plexus.core, parent: null]
[DEBUG] Extension realms for project org.felipe:tutorial_maven_webapp:war:1.0-SNAPSHOT: (none)
[DEBUG] Looking up lifecyle mappings for packaging war from ClassRealm[plexus.core, parent: null]
[ERROR] The build could not read 1 project -> [Help 1]
org.apache.maven.project.ProjectBuildingException: Some problems were encountered while processing the POMs:
[WARNING] 'parent.relativePath' points at org.felipe:tutorial_maven instead of ${parent.groupId}:tutorial_maven, please verify your project structure @ line 3, column 13
[FATAL] Non-resolvable parent POM: Could not transfer artifact ${parent.groupId}:tutorial_maven:pom:${parent.version} from/to central (http://repo.maven.apache.org/maven2): Illegal character in path at index 37: http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tutorial_maven-${parent.version}.pom and 'parent.relativePath' points at wrong local POM @ line 3, column 13

at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:363)
at org.apache.maven.DefaultMaven.collectProjects(DefaultMaven.java:636)
at org.apache.maven.DefaultMaven.getProjectsForMavenReactor(DefaultMaven.java:585)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:234)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)
at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
[ERROR]   
[ERROR]   The project ${parent.groupId}:tutorial_maven_jar:${parent.version} (C:\Users\fureta.DESARROLLO03\IdeaProjects\tutorial_maven\tutorial_maven_jar\pom.xml) has 1 error
[ERROR]     Non-resolvable parent POM: Could not transfer artifact  ${parent.groupId}:tutorial_maven:pom:${parent.version} from/to central  (http://repo.maven.apache.org/maven2): Illegal character in path at index 37:  http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tuto rial_maven-${parent.version}.pom and 'parent.relativePath' points at wrong local POM @ line  3, column 13 -> [Help 2]
org.apache.maven.model.resolution.UnresolvableModelException: Could not transfer  artifact ${parent.groupId}:tutorial_maven:pom:${parent.version} from/to central  (http://repo.maven.apache.org/maven2): Illegal character in path at index 37:  http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tuto rial_maven-${parent.version}.pom
at  org.apache.maven.project.ProjectModelResolver.resolveModel(ProjectModelResolver.java:159)
at org.apache.maven.model.building.DefaultModelBuilder.readParentExternally(DefaultModelBuilder.java:813)
at org.apache.maven.model.building.DefaultModelBuilder.readParent(DefaultModelBuilder.java:664)
at org.apache.maven.model.building.DefaultModelBuilder.build(DefaultModelBuilder.java:310)
at org.apache.maven.model.building.DefaultModelBuilder.build(DefaultModelBuilder.java:232)
at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:410)
at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:379)
at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:495)
at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:379)
at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:343)
at org.apache.maven.DefaultMaven.collectProjects(DefaultMaven.java:636)
at org.apache.maven.DefaultMaven.getProjectsForMavenReactor(DefaultMaven.java:585)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:234)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)
at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
Caused by: org.sonatype.aether.resolution.ArtifactResolutionException: Could not  transfer artifact ${parent.groupId}:tutorial_maven:pom:${parent.version} from/to central  (http://repo.maven.apache.org/maven2): Illegal character in path at index 37:  http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tuto rial_maven-${parent.version}.pom
at  org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:538)
at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:216)
at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolveArtifact(DefaultArtifactResolver.java:193)
at org.sonatype.aether.impl.internal.DefaultRepositorySystem.resolveArtifact(DefaultRepositorySystem.java:286)
at org.apache.maven.project.ProjectModelResolver.resolveModel(ProjectModelResolver.java:155)
... 30 more
Caused by: org.sonatype.aether.transfer.ArtifactTransferException: Could not transfer artifact ${parent.groupId}:tutorial_maven:pom:${parent.version} from/to central (http://repo.maven.apache.org/maven2): Illegal character in path at index 37: http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tutorial_maven-${parent.version}.pom
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$4.wrap(WagonRepositoryConnector.java:951)
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$4.wrap(WagonRepositoryConnector.java:941)
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$GetTask.run(WagonRepositoryConnector.java:669)
at org.sonatype.aether.util.concurrency.RunnableErrorForwarder$1.run(RunnableErrorForwarder.java:60)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
Caused by: java.lang.IllegalArgumentException: Illegal character in path at index 37: http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tutorial_maven-${parent.version}.pom
at java.net.URI.create(URI.java:859)
at org.apache.maven.wagon.providers.http.httpclient.client.methods.HttpGet.<init>(HttpGet.java:69)
at org.apache.maven.wagon.shared.http4.AbstractHttpClientWagon.fillInputData(AbstractHttpClientWagon.java:778)
at org.apache.maven.wagon.StreamWagon.getInputStream(StreamWagon.java:116)
at org.apache.maven.wagon.StreamWagon.getIfNewer(StreamWagon.java:88)
at org.apache.maven.wagon.StreamWagon.get(StreamWagon.java:61)
at      org.sonatype.aether.connector.wagon.WagonRepositoryConnector$GetTask.run(WagonRepositoryConnector.java:601)
... 4 more
Caused by: java.net.URISyntaxException: Illegal character in path at index 37: http://repo.maven.apache.org/maven2/${parent/groupId}/tutorial_maven/${parent.version}/tutorial_maven-${parent.version}.pom
at java.net.URI$Parser.fail(URI.java:2829)
at java.net.URI$Parser.checkChars(URI.java:3002)
at java.net.URI$Parser.parseHierarchical(URI.java:3086)
at java.net.URI$Parser.parse(URI.java:3034)
at java.net.URI.<init>(URI.java:595)
at java.net.URI.create(URI.java:857)
... 10 more
[ERROR] 
[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/ProjectBuildingException
[ERROR] [Help 2]   http://cwiki.apache.org/confluence/display/MAVEN/UnresolvableModelException

I've read through the links at Help 1 and Help 2 but found nothing that helps. From what I can understand from the logs is that maven is looking for my main pom in the maven repositories...

What am I missing?

My main pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0  http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>org.felipe</groupId>
  <artifactId>tutorial_maven</artifactId>
  <version>1.0-SNAPSHOT</version>
    <modules>
        <module>tutorial_maven_jar</module>
        <module>tutorial_maven_webapp</module>
    </modules>
    <packaging>pom</packaging>

  <name>tutorial_maven</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <!--<log4j.version>1.2.17</log4j.version>-->
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

my module pom.xml:

<project xmlns="http://maven.apache.org/POM/4.0.0"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0   http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>tutorial_maven</artifactId>
        <groupId>${parent.groupId}</groupId>
        <version>${parent.version}</version>
        <relativePath>../pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>tutorial_maven_jar</artifactId>
    <packaging>jar</packaging>

    <name>tutorial_maven_jar</name>
    <url>http://maven.apache.org</url>

    <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
            <!--<optional>true</optional>-->
        </dependency>

        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
    </dependencies>
</project>

Best regards, Felipe

Forging

Answer 1

Looks like you're trying to both inherit the groupId from the parent, and simultaneously specify the parent using an inherited groupId!

In the child pom, use something like this:

<modelVersion>4.0.0</modelVersion>

<parent>
  <groupId>org.felipe</groupId>
  <artifactId>tutorial_maven</artifactId>
  <version>1.0-SNAPSHOT</version>
  <relativePath>../pom.xml</relativePath>
</parent>

<artifactId>tutorial_maven_jar</artifactId>

Using properties like ${project.groupId} won't work there. If you specify the parent in this way, then you can inherit the groupId and version in the child pom. Hence, you only need to specify the artifactId in the child pom.

Prohibitory

Hello Martin, that is how I originally had it and I was following along the tutorial, maybe I am missunderstanding the tutorial. From what I see, if I change the version in the Parent pom then I have to change de version on the child poms manually? – Forging

Yes, but you can use the versions plugin to automate that, so you don't have to edit each one by hand. If you run mvn versions:set -DnewVersion=x.y.z from the top-level pom, then it will set this version on the top-level pom on all sub-modules. For more information see: mojo.codehaus.org/versions-maven-plugin/set-mojo.html – Prohibitory

Answer 2

I assume the question is already answered. If above solution doesn't help in solving the issue then can use below to solve the issue.

The issue occurs if sometimes your maven user settings is not reflecting correct settings.xml file.

To update the settings file go to Windows > Preferences > Maven > User Settings and update the settings.xml to it correct location.

Once this is doen re-build the project, these should solve the issue. Thanks.

Taam

Good suggestion. I checked and unfortunately the location of my settings.xml file is correct. – Szymanowski

Answer 3

I had the same issue. Fixed by adding a pom.xml in parent folder with <modules> listed.

Palaeontology

Answer 4

As Nayan said the Path has to updated properly in my case the apache-maven was installed in C:\apache-maven and settings.xml was found inside C:\apache-maven\conf\settings.xml

if this doesn't work go to your local repos
in my case C:\Users\<<"name">>.m2\
and search for .lastUpdated and delete them
then build the maven

Agler