[MDEP-645] Created new mojo GetClassesMojo which lists all class dependencies for a specified artifact.

src/main/java/org/apache/maven/plugins/dependency/ListClassesMojo.java

@@ -0,0 +1,326 @@
+package org.apache.maven.plugins.dependency;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.List;
+import java.util.Map;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.apache.maven.artifact.handler.ArtifactHandler;
+import org.apache.maven.artifact.handler.manager.ArtifactHandlerManager;
+import org.apache.maven.artifact.repository.ArtifactRepository;
+import org.apache.maven.artifact.repository.ArtifactRepositoryPolicy;
+import org.apache.maven.artifact.repository.MavenArtifactRepository;
+import org.apache.maven.artifact.repository.layout.ArtifactRepositoryLayout;
+import org.apache.maven.execution.MavenSession;
+import org.apache.maven.plugin.AbstractMojo;
+import org.apache.maven.plugin.MojoExecutionException;
+import org.apache.maven.plugin.MojoFailureException;
+import org.apache.maven.plugins.annotations.Component;
+import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.Parameter;
+import org.apache.maven.project.DefaultProjectBuildingRequest;
+import org.apache.maven.project.ProjectBuildingRequest;
+import org.apache.maven.repository.RepositorySystem;
+import org.apache.maven.settings.Settings;
+import org.apache.maven.shared.transfer.artifact.ArtifactCoordinate;
+import org.apache.maven.shared.transfer.artifact.DefaultArtifactCoordinate;
+import org.apache.maven.shared.transfer.artifact.resolve.ArtifactResolver;
+import org.apache.maven.shared.transfer.artifact.resolve.ArtifactResolverException;
+import org.apache.maven.shared.transfer.artifact.resolve.ArtifactResult;
+import org.apache.maven.shared.transfer.dependencies.DefaultDependableCoordinate;
+import org.apache.maven.shared.transfer.dependencies.DependableCoordinate;
+import org.apache.maven.shared.transfer.dependencies.resolve.DependencyResolver;
+import org.apache.maven.shared.transfer.dependencies.resolve.DependencyResolverException;
+
+
+/**
+ * Retrieves and lists all classes contained in the specified artifact from the specified remote repositories.
+ */
+@Mojo( name = "list-classes", requiresProject = false, threadSafe = true )
+public class ListClassesMojo
+    extends AbstractMojo
+{
+    private static final Pattern ALT_REPO_SYNTAX_PATTERN = Pattern.compile( "(.+)::(.*)::(.+)" );
+
+    @Parameter( defaultValue = "${session}", required = true, readonly = true )
+    private MavenSession session;
+
+    @Component
+    private ArtifactResolver artifactResolver;
+
+    @Component
+    private DependencyResolver dependencyResolver;
+
+    @Component
+    private ArtifactHandlerManager artifactHandlerManager;
+
+    /**
+     * Map that contains the layouts.
+     */
+    @Component( role = ArtifactRepositoryLayout.class )
+    private Map<String, ArtifactRepositoryLayout> repositoryLayouts;
+
+    /**
+     * The repository system.
+     */
+    @Component
+    private RepositorySystem repositorySystem;
+
+    private DefaultDependableCoordinate coordinate = new DefaultDependableCoordinate();
+
+    /**
+     * The group ID of the artifact to download. Ignored if {@link #artifact} is used.
+     */
+    @Parameter( property = "groupId" )
+    private String groupId;
+
+    /**
+     * The artifact ID of the artifact to download. Ignored if {@link #artifact} is used.
+     */
+    @Parameter( property = "artifactId" )
+    private String artifactId;
+
+    /**
+     * The version of the artifact to download. Ignored if {@link #artifact} is used.
+     */
+    @Parameter( property = "version" )
+    private String version;
+
+    /**
+     * The classifier of the artifact to download. Ignored if {@link #artifact} is used.
+     *
+     * @since 2.3
+     */
+    @Parameter( property = "classifier" )
+    private String classifier;
+
+    /**
+     * The packaging of the artifact to download. Ignored if {@link #artifact} is used.
+     */
+    @Parameter( property = "packaging", defaultValue = "jar" )
+    private String packaging = "jar";
+
+    /**
+     * Repositories in the format id::[layout]::url or just URLs, separated by comma. That is,
+     * central::default::https://repo.maven.apache.org/maven2,myrepo::::https://repo.acme.com,https://repo.acme2.com
+     */
+    @Parameter( property = "remoteRepositories" )
+    private String remoteRepositories;
+
+    /**
+     * A string of the form groupId:artifactId:version[:packaging[:classifier]].
+     */
+    @Parameter( property = "artifact" )
+    private String artifact;
+
+    @Parameter( defaultValue = "${project.remoteArtifactRepositories}", readonly = true, required = true )
+    private List<ArtifactRepository> pomRemoteRepositories;
+
+    /**
+     * Download transitively, retrieving the specified artifact and all of its dependencies.
+     */
+    @Parameter( property = "transitive", defaultValue = "false" )
+    private boolean transitive = false;
+
+    /**
+     * Skip plugin execution completely.
+     */
+    @Parameter( property = "mdep.skip", defaultValue = "false" )
+    private boolean skip;
+
+    @Override
+    public void execute() throws MojoExecutionException, MojoFailureException
+    {
+        ProjectBuildingRequest buildingRequest = makeBuildingRequest();
+
+        try
+        {
+            if ( transitive )
+            {
+                Iterable<ArtifactResult> artifacts = dependencyResolver
+                        .resolveDependencies( buildingRequest, coordinate, null );
+
+                for ( ArtifactResult result : artifacts )
+                {
+                    printClassesFromArtifactResult( result );
+                }
+            }
+            else
+            {
+                ArtifactResult result = artifactResolver
+                        .resolveArtifact( buildingRequest, toArtifactCoordinate( coordinate ) );
+
+                printClassesFromArtifactResult( result );
+            }
+        }
+        catch ( ArtifactResolverException | DependencyResolverException | IOException e )
+        {
+            throw new MojoExecutionException( "Couldn't download artifact: " + e.getMessage(), e );
+        }
+    }
+
+    private void printClassesFromArtifactResult( ArtifactResult result )
+            throws IOException
+    {
+        // open jar file in try-with-resources statement to guarantee the file closes after use regardless of errors
+        try ( JarFile jarFile = new JarFile( result.getArtifact().getFile() ) )
+        {
+            Enumeration entries = jarFile.entries();
+
+            while ( entries.hasMoreElements() )
+            {
+                JarEntry entry = (JarEntry) entries.nextElement();
+                String entryName = entry.getName();
+
+                // filter out files that do not end in .class
+                if ( !entryName.endsWith( ".class" ) )
+                {
+                    continue;
+                }
+
+                // remove .class from the end and change format to use periods instead of forward slashes
+                String className = entryName.substring( 0, entryName.length() - 6 ).replace( '/', '.' );
+                getLog().info( className );
+            }
+        }
+    }
+
+    private ProjectBuildingRequest makeBuildingRequest()
+            throws MojoExecutionException, MojoFailureException
+    {
+        if ( artifact == null )
+        {
+            throw new MojoFailureException( "You must specify an artifact, "
+                    + "e.g. -Dartifact=org.apache.maven.plugins:maven-downloader-plugin:1.0" );
+        }
+        if ( artifact != null )
+        {
+            String[] tokens = artifact.split( ":" );
+            if ( tokens.length < 3 || tokens.length > 5 )
+            {
+                throw new MojoFailureException( "Invalid artifact, you must specify "
+                        + "groupId:artifactId:version[:packaging[:classifier]] " + artifact );
+            }
+            coordinate.setGroupId( tokens[0] );
+            coordinate.setArtifactId( tokens[1] );
+            coordinate.setVersion( tokens[2] );
+            if ( tokens.length >= 4 )
+            {
+                coordinate.setType( tokens[3] );
+            }
+            if ( tokens.length == 5 )
+            {
+                coordinate.setClassifier( tokens[4] );
+            }
+        }
+
+        ArtifactRepositoryPolicy always =
+                new ArtifactRepositoryPolicy( true, ArtifactRepositoryPolicy.UPDATE_POLICY_ALWAYS,
+                        ArtifactRepositoryPolicy.CHECKSUM_POLICY_WARN );
+
+        List<ArtifactRepository> repoList = new ArrayList<>();
+
+        if ( pomRemoteRepositories != null )
+        {
+            repoList.addAll( pomRemoteRepositories );
+        }
+
+        if ( remoteRepositories != null )
+        {
+            // Use the same format as in the deploy plugin id::layout::url
+            String[] repos = remoteRepositories.split( "," );
+            for ( String repo : repos )
+            {
+                repoList.add( parseRepository( repo, always ) );
+            }
+        }
+
+        ProjectBuildingRequest buildingRequest =
+                new DefaultProjectBuildingRequest( session.getProjectBuildingRequest() );
+
+        Settings settings = session.getSettings();
+        repositorySystem.injectMirror( repoList, settings.getMirrors() );
+        repositorySystem.injectProxy( repoList, settings.getProxies() );
+        repositorySystem.injectAuthentication( repoList, settings.getServers() );
+
+        buildingRequest.setRemoteRepositories( repoList );
+
+        return buildingRequest;
+    }
+
+    protected ArtifactCoordinate toArtifactCoordinate( DependableCoordinate dependableCoordinate )
+    {
+        ArtifactHandler artifactHandler = artifactHandlerManager.getArtifactHandler( dependableCoordinate.getType() );
+        DefaultArtifactCoordinate artifactCoordinate = new DefaultArtifactCoordinate();
+        artifactCoordinate.setGroupId( dependableCoordinate.getGroupId() );
+        artifactCoordinate.setArtifactId( dependableCoordinate.getArtifactId() );
+        artifactCoordinate.setVersion( dependableCoordinate.getVersion() );
+        artifactCoordinate.setClassifier( dependableCoordinate.getClassifier() );
+        artifactCoordinate.setExtension( artifactHandler.getExtension() );
+        return artifactCoordinate;
+    }
+
+    protected ArtifactRepository parseRepository( String repo, ArtifactRepositoryPolicy policy )
+            throws MojoFailureException
+    {
+        // if it's a simple url
+        String id = "temp";
+        ArtifactRepositoryLayout layout = getLayout( "default" );
+
+        // if it's an extended repo URL of the form id::layout::url
+        if ( repo.contains( "::" ) )
+        {
+            Matcher matcher = ALT_REPO_SYNTAX_PATTERN.matcher( repo );
+            if ( !matcher.matches() )
+            {
+                throw new MojoFailureException( repo, "Invalid syntax for repository: " + repo,
+                        "Invalid syntax for repository. Use \"id::layout::url\" or \"URL\"." );
+            }
+
+            id = matcher.group( 1 ).trim();
+            if ( !( matcher.group( 2 ) == null || matcher.group( 2 ).trim().isEmpty() ) )
+            {
+                layout = getLayout( matcher.group( 2 ).trim() );
+            }
+            repo = matcher.group( 3 ).trim();
+        }
+        return new MavenArtifactRepository( id, repo, layout, policy, policy );
+    }
+
+    private ArtifactRepositoryLayout getLayout( String id )
+            throws MojoFailureException
+    {
+        ArtifactRepositoryLayout layout = repositoryLayouts.get( id );
+
+        if ( layout == null )
+        {
+            throw new MojoFailureException( id, "Invalid repository layout", "Invalid repository layout: " + id );
+        }
+
+        return layout;
+    }
+}