Maven 不解析本地父 POM

Question

这是一个有趣的问题，我不知道是我做错了什么还是 Maven 的限制。

该场景的最简单版本是有一个父 POM、单个子 POM 和一个聚合 POM。聚合 POM 只是将模块链接在一起。

当我安装聚合 POM 时，它没有找出子 POM 对父 POM 的依赖关系。我不希望有相对路径，根据我对 Maven 工件的理解应该是可能的。

任何见解将不胜感激。谢谢。

这是超级父级（别介意里面什么都没有）

<project>
    <modelVersion>4.0.0</modelVersion>
    <groupId>my.group</groupId>
    <artifactId>parent-uber</artifactId>
    <version>0.0.2-SNAPSHOT</version>
    <packaging>pom</packaging>

</project>

这是孩子：

<?xml version="1.0" encoding="UTF-8"?>
<project>
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>my.group</groupId>
        <artifactId>parent-uber</artifactId>
        <version>0.0.2-SNAPSHOT</version>
    </parent>

    <groupId>my.group</groupId>
    <artifactId>parent-java</artifactId>
    <packaging>pom</packaging>

    <properties>
    </properties>

    <build>
        <!-- To define the plugin version in your parent POM -->
        <pluginManagement>
            <plugins>
                <!-- All projects that extend this should have valid JavaDoc built-->
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-javadoc-plugin</artifactId>
                    <executions>
                        <execution>
                            <id>attach-javadocs</id>
                            <goals>
                                <goal>jar</goal>
                            </goals>
                        </execution>
                    </executions>
                </plugin>
            </plugins>
        </pluginManagement>
    </build>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.11</version>
                <scope>test</scope>
            </dependency>    
            <dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>1.2.17</version>
            </dependency>    
            <dependency>
                <groupId>commons-lang</groupId>
                <artifactId>commons-lang</artifactId>
                <version>2.1</version>
            </dependency>    
            <dependency>
                <groupId>commons-io</groupId>
                <artifactId>commons-io</artifactId>
                <version>2.4</version>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

为了完整性，聚合器：

<project>
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>my.group</groupId>
        <artifactId>_maven-integration-aggregator</artifactId>
        <version>0.1-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath> <!-- parent aggregator -->
    </parent>

    <groupId>my.group.maven</groupId>
    <artifactId>_poms-aggregator</artifactId>
    <version>0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <modules>
        <module>parent-uber</module>
        <module>parent-java</module>
    </modules>

</project>

错误：

org.apache.maven.model.resolution.UnresolvableModelException: Could not find artifact my.group:parent-uber:pom:0.0.2-SNAPSHOT
    at org.apache.maven.project.ProjectModelResolver.resolveModel(ProjectModelResolver.java:159)
    at org.apache.maven.model.building.DefaultModelBuilder.readParentExternally(DefaultModelBuilder.java:817)
    at org.apache.maven.model.building.DefaultModelBuilder.readParent(DefaultModelBuilder.java:669)
    at org.apache.maven.model.building.DefaultModelBuilder.build(DefaultModelBuilder.java:307)
    at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:411)
    at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:380)
    at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:496)
    at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:380)
    at org.apache.maven.project.DefaultProjectBuilder.build(DefaultProjectBuilder.java:344)
    at org.apache.maven.DefaultMaven.collectProjects(DefaultMaven.java:637)
    at org.apache.maven.DefaultMaven.getProjectsForMavenReactor(DefaultMaven.java:586)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:229)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:152)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:555)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:214)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:158)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.eclipse.aether.resolution.ArtifactResolutionException: Could not find artifact my.group:parent-uber:pom:0.0.2-SNAPSHOT
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:459)
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:262)
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifact(DefaultArtifactResolver.java:239)
    at org.eclipse.aether.internal.impl.DefaultRepositorySystem.resolveArtifact(DefaultRepositorySystem.java:295)
    at org.apache.maven.project.ProjectModelResolver.resolveModel(ProjectModelResolver.java:155)
    ... 23 more
Caused by: org.eclipse.aether.transfer.ArtifactNotFoundException: Could not find artifact my.parent:parent-uber:pom:0.0.2-SNAPSHOT
    at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:449)
    ... 27 more

Answer 1

我不知道这是否能解决您的问题，但是：

当指定父 pom 时，maven默认情况下假定它位于父文件夹中。这不是你的情况，所以你必须重新定义parent-java的父部分中的相对路径以指向../parent-uber，并且pom将在本地解析，或者作为<relativePath />，它将在远程解析。