以编程方式解析插件之外的Maven依赖关系 – 获取RepositorySystemSession和RepositorySystem
也许这将是一个比我原先想象的更大的任务，但无论如何，我正在尝试从文件加载MavenProject然后解决它的依赖关系。 我有两个位的代码，但我缺少一些我需要的对象引用; 特别是我需要获取RepositorySystemSession和RepositorySystem实例。 有小费吗？
注意：我用maven-plugin标记了这个问题，但这不是Maven插件。 我很高兴要求Maven 3（不管怎么说我已经有了……）
这是我到目前为止的代码：
构建MavenProject ：
public static MavenProject loadProject(File pomFile) throws Exception { MavenProject ret = null; MavenXpp3Reader mavenReader = new MavenXpp3Reader(); if (pomFile != null && pomFile.exists()) { FileReader reader = null; try { reader = new FileReader(pomFile); Model model = mavenReader.read(reader); model.setPomFile(pomFile); ret = new MavenProject(model); } finally { // Close reader } } return ret; }
解决依赖关系：
public static List getArtifactsDependencies(MavenProject project, String dependencyType, String scope) throws Exception { DefaultArtifact pomArtifact = new DefaultArtifact(project.getId()); RepositorySystemSession repoSession = null; // TODO RepositorySystem repoSystem = null; // TODO List remoteRepos = project.getRemoteProjectRepositories(); List ret = new ArrayList(); Dependency dependency = new Dependency(pomArtifact, scope); CollectRequest collectRequest = new CollectRequest(); collectRequest.setRoot(dependency); collectRequest.setRepositories(remoteRepos); DependencyNode node = repoSystem.collectDependencies(repoSession, collectRequest).getRoot(); DependencyRequest projectDependencyRequest = new DependencyRequest(node, null); repoSystem.resolveDependencies(repoSession, projectDependencyRequest); PreorderNodeListGenerator nlg = new PreorderNodeListGenerator(); node.accept(nlg); ret.addAll(nlg.getDependencies(true)); return ret; }
我意识到这可能是一个不寻常的请求，也许我应该废弃我想要做的事情并将其作为插件包装……但我只是想完成我现在开始的事情！ 提前致谢。
试试jcabi-aether ，它是来自Sonatype的Apache Aether的包装：
final File repo = this.session.getLocalRepository().getBasedir(); final Collection deps = new Aether(this.getProject(), repo).resolve( new DefaultArtifact("junit", "junit-dep", "", "jar", "4.10"), JavaScopes.RUNTIME );
如果你不在Maven插件中：
final File repo = new File(System.getProperty("java.io.tmpdir"), "my-repo"); final MavenProject project = new MavenProject(); project.setRemoteArtifactRepositories( Arrays.asList( new RemoteRepository( "maven-central", "default", "http://repo1.maven.org/maven2/" ) ) ); final Collection deps = new Aether(project, repo).resolve( new DefaultArtifact("junit", "junit-dep", "", "jar", "4.10"), JavaScopes.RUNTIME );
我建议阅读有关Aether lib的信息，这正是出于这种目的。
注意：Aether之前是在Sonatype开发的，但后来转移到了Eclipse 。
我刚刚为你和我的问题提出了一个解决方案：
/******************************************************************************* * Copyright (c) 2013 TerraFrame, Inc. All rights reserved. * * This file is part of Runway SDK(tm). * * Runway SDK(tm) is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * Runway SDK(tm) is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Runway SDK(tm). If not, see dependencies = proj.getDependencies(); Iterator it = dependencies.iterator(); while (it.hasNext()) { org.apache.maven.model.Dependency depend = it.next(); final Collection deps = aether.resolve( new DefaultArtifact(depend.getGroupId(), depend.getArtifactId(), depend.getClassifier(), depend.getType(), depend.getVersion()), JavaScopes.RUNTIME ); Iterator artIt = deps.iterator(); while (artIt.hasNext()) { Artifact art = artIt.next(); classpath = classpath + " " + art.getFile().getAbsolutePath(); } } return classpath; } public static MavenProject loadProject(File pomFile) throws IOException, XmlPullParserException { MavenProject ret = null; MavenXpp3Reader mavenReader = new MavenXpp3Reader(); if (pomFile != null && pomFile.exists()) { FileReader reader = null; try { reader = new FileReader(pomFile); Model model = mavenReader.read(reader); model.setPomFile(pomFile); ret = new MavenProject(model); } finally { reader.close(); } } return ret; } }
pom.xml中：
4.0.0 com.test MavenSandbox 0.0.1-SNAPSHOT com.jcabi jcabi-aether 0.7.19 org.apache.maven maven-core 3.0.3
代码首先加载Maven项目（使用原始问题中提供的函数），然后使用jcabi-aether在本地存储库中查找工件。 您需要更改main函数中的两个参数：项目的pom.xml的位置以及本地存储库的位置。
请享用！ 🙂
试试这个（从ather-demo可以看出）：
... LocalRepository localRepository = new LocalRepository("/path/to/local-repo"); RepositorySystem system = getRepositorySystemInstance(); RepositorySystemSession session = getRepositorySystemSessionInstance(system, localRepository); .... public static RepositorySystem getRepositorySystemInstance() { /** * Aether's components implement org.sonatype.aether.spi.locator.Service to ease manual wiring and using the * prepopulated DefaultServiceLocator, we only need to register the repository connector factories. */ MavenServiceLocator locator = new MavenServiceLocator(); locator.addService(RepositoryConnectorFactory.class, FileRepositoryConnectorFactory.class); locator.addService(RepositoryConnectorFactory.class, WagonRepositoryConnectorFactory.class); locator.setServices(WagonProvider.class, new ManualWagonProvider()); return locator.getService(RepositorySystem.class); } private static RepositorySystemSession getRepositorySystemSessionInstance(RepositorySystem system, LocalRepository localRepo) { MavenRepositorySystemSession session = new MavenRepositorySystemSession(); session.setLocalRepositoryManager(system.newLocalRepositoryManager(localRepo)); session.setTransferListener(new ConsoleTransferListener()); session.setRepositoryListener(new ConsoleRepositoryListener()); // Set this in order to generate dirty trees session.setDependencyGraphTransformer(null); return session; }
Eclipses Aether API有一套很好的独立示例，它们在最新的Maven（3.1.1）中使用，可以在这里找到。
注意：Maven 3.1.X仍然使用Aether 0.9.0.M2 （我们在示例中使用的最新版本是0.9.0.M3 ）。 因此，要在Maven插件中运行这些示例，需要版本M2，并且独立应用程序可以使用最新的M3版本。
这在RepositorySystem的“Aether / Setting Aether Up”和eclipse wiki中的“Aether / Creating a Repository System Session”中有所介绍。
没有大量文档，但您可以按如下方式创建RepositorySystem：
// verbatim copy from the Setting Aether Up link private static RepositorySystem newRepositorySystem() { DefaultServiceLocator locator = MavenRepositorySystemUtils.newServiceLocator(); locator.addService( RepositoryConnectorFactory.class, BasicRepositoryConnectorFactory.class ); locator.addService( TransporterFactory.class, FileTransporterFactory.class ); locator.addService( TransporterFactory.class, HttpTransporterFactory.class ); return locator.getService( RepositorySystem.class ); }
请注意，这需要“获取以太”中详述的依赖关系，最明显的是maven-aether-provider 。
当您拥有存储库系统时，本教程将继续使用以下工厂方法创建RepositorySystemSession：
// copied verbatim from "Creating a Repository System Session" private static RepositorySystemSession newSession( RepositorySystem system ) { DefaultRepositorySystemSession session = MavenRepositorySystemUtils.newSession(); LocalRepository localRepo = new LocalRepository( "target/local-repo" ); session.setLocalRepositoryManager( system.newLocalRepositoryManager( session, localRepo ) ); return session; }