Add shading analyzer

.gitignore

@@ -13,3 +13,4 @@ out/
 /bootstrap
 /dependencies.xml
 .java-version
+logs

checkstyle/checkstyle-suppressions.xml

@@ -31,8 +31,12 @@ under the License.
     <!-- Allow magic numbers in Maven plugin parameter defaults -->
     <suppress checks="MagicNumber" files=".*Mojo\.java"/>
 
-    <!-- Allow hidden fields for Maven plugin parameters -->
+    <!-- Allow hidden fields for Maven plugin parameters and constructor parameters -->
     <suppress checks="HiddenField" files=".*Mojo\.java"/>
+    <suppress checks="HiddenField" files=".*\.java"/>
+
+    <!-- Allow single-line if statements without braces -->
+    <suppress checks="NeedBraces" files=".*\.java"/>
 
     <!-- Allow protected/public fields for Maven plugin parameters -->
     <suppress checks="VisibilityModifier" files=".*Mojo\.java"/>

src/main/java/com/github/streamshub/AbstractAlignmentReporterMojo.java

@@ -146,6 +146,42 @@ public abstract class AbstractAlignmentReporterMojo extends AbstractMojo {
     @Parameter(property = "excludes")
     private String excludes;
 
+    /**
+     * A comma-separated list of module names to exclude from processing in multi-module projects, or <code>null</code> to
+     * include all modules. Each module name pattern supports full and partial <code>*</code> wildcards.
+     * <p>
+     * For example, <code>*-test</code> will exclude all modules whose name ends with "-test",
+     * and <code>flink-*</code> will exclude all modules whose name starts with "flink-".
+     * </p>
+     */
+    @Parameter(property = "excludeModules")
+    private String excludeModules;
+
+    /**
+     * Enable shade-aware analysis to detect and report on maven-shade-plugin configurations and their alignment.
+     * When enabled, the plugin will analyze shade configurations across all projects and provide additional
+     * reporting on shaded dependencies.
+     */
+    @Parameter(property = "analyzeShade", defaultValue = "false")
+    private boolean analyzeShade;
+
+    /**
+     * Print detailed shade configuration information in the report.
+     * Only has effect when analyzeShade=true. When enabled, shows all shade plugin configurations
+     * found in the project with their relocation mappings.
+     */
+    @Parameter(property = "printShadeConfigurations", defaultValue = "false")
+    private boolean printShadeConfigurations;
+
+    /**
+     * Include transitive dependencies in shade analysis.
+     * Only has effect when analyzeShade=true. When enabled, analyzes both direct and transitive
+     * dependencies for shade impact, providing comprehensive coverage of all artifacts that
+     * could be affected by shading configurations.
+     */
+    @Parameter(property = "includeTransitiveShaded", defaultValue = "false")
+    private boolean includeTransitiveShaded;
+
     private ArtifactFilter scopeFilter;
 
     private static void write(final String string, final File file) throws IOException {
@@ -224,6 +260,37 @@ public void execute() throws MojoExecutionException, MojoFailureException {
             String unalignedTransitivesStr = reportUnalignedTransitiveDependenciesSummary(unalignedTransitives);
             String unalignedTransitiveDetail = reportUnalignedTransitiveDependencyDetail(alignedDirectDeps, excludeDependencyFilter);
 
+            String shadeReport = "";
+            String shadeAlignmentSummary = "";
+
+            if (analyzeShade) {
+                ShadeAwareAlignmentReporter shadeReporter = new ShadeAwareAlignmentReporter(getLog());
+
+                // Collect artifacts for shade analysis
+                List<Artifact> artifactsForShadeAnalysis;
+                List<ArtifactWithPath> artifactsWithPathsForShadeAnalysis = null;
+
+                if (includeTransitiveShaded) {
+                    artifactsWithPathsForShadeAnalysis = getAllTransitiveDependencyArtifactsWithPaths(directDependencies);
+                    artifactsForShadeAnalysis = artifactsWithPathsForShadeAnalysis.stream()
+                        .map(ArtifactWithPath::getArtifact)
+                        .collect(Collectors.toList());
+                } else {
+                    artifactsForShadeAnalysis = new ArrayList<>(dependencyArtifacts);
+                }
+
+                ShadeAwareAlignmentReporter.ShadeAlignmentResult shadeResult =
+                    shadeReporter.analyzeShadeAlignment(getReactorProjectsForShadeAnalysis(),
+                        artifactsForShadeAnalysis,
+                        alignmentPattern,
+                        artifactsWithPathsForShadeAnalysis);
+
+                if (printShadeConfigurations) {
+                    shadeReport = shadeReporter.generateShadeReport(shadeResult, alignmentPattern);
+                }
+                shadeAlignmentSummary = shadeReporter.generateShadeAlignmentSummary(shadeResult, alignmentPattern);
+            }
+
             if (outputFile != null) {
                 String projectTitle = getProjectTitle();
 
@@ -233,13 +300,27 @@ public void execute() throws MojoExecutionException, MojoFailureException {
                 write(unalignedTransitivesStr, outputFile);
                 write(unalignedTransitiveDetail, outputFile);
 
+                if (analyzeShade && !shadeReport.isEmpty()) {
+                    write(shadeReport, outputFile);
+                }
+                if (analyzeShade && !shadeAlignmentSummary.isEmpty()) {
+                    write(shadeAlignmentSummary, outputFile);
+                }
+
                 getLog().info(String.format("Wrote alignment report tree to: %s",
                     outputFile));
             } else {
                 log(alignedDirectStr, getLog());
                 log(unalignedDirectStr, getLog());
                 log(unalignedTransitivesStr, getLog());
                 log(unalignedTransitiveDetail, getLog());
+
+                if (analyzeShade && !shadeReport.isEmpty()) {
+                    log(shadeReport, getLog());
+                }
+                if (analyzeShade && !shadeAlignmentSummary.isEmpty()) {
+                    log(shadeAlignmentSummary, getLog());
+                }
             }
         } catch (IOException exception) {
             throw new MojoExecutionException(
@@ -558,4 +639,121 @@ private ArtifactFilter createExcludeFilter() {
         }
         return filter;
     }
+
+    /**
+     * Filters reactor projects based on the excludeModules parameter.
+     *
+     * @param projects the list of projects to filter
+     * @return the filtered list of projects
+     */
+    protected List<MavenProject> filterModules(final List<MavenProject> projects) {
+        if (excludeModules == null || excludeModules.trim()
+            .isEmpty()) {
+            return projects;
+        }
+
+        List<String> patterns = Arrays.asList(excludeModules.split(","));
+        getLog().debug(String.format("+ Filtering modules by exclude patterns: %s", patterns));
+
+        return projects.stream()
+            .filter(project -> {
+                String artifactId = project.getArtifactId();
+                for (String pattern : patterns) {
+                    String trimmedPattern = pattern.trim();
+                    if (matchesPattern(artifactId, trimmedPattern)) {
+                        getLog().debug(String.format("+ Excluding module: %s (matched pattern: %s)", artifactId, trimmedPattern));
+                        return false;
+                    }
+                }
+                return true;
+            })
+            .collect(Collectors.toList());
+    }
+
+    /**
+     * Checks if a string matches a pattern with wildcard support.
+     *
+     * @param text    the text to match
+     * @param pattern the pattern (supports * wildcards)
+     * @return true if the text matches the pattern
+     */
+    private boolean matchesPattern(final String text, final String pattern) {
+        if (pattern.equals("*")) {
+            return true;
+        }
+
+        String regex = pattern.replace("*", ".*");
+        return text.matches(regex);
+    }
+
+    /**
+     * Gets the reactor projects to use for shade analysis.
+     * In single-module mode, returns only the current project.
+     * In aggregate mode, returns filtered reactor projects.
+     *
+     * @return the list of projects for shade analysis
+     */
+    protected List<MavenProject> getReactorProjectsForShadeAnalysis() {
+        return filterModules(reactorProjects);
+    }
+
+    /**
+     * Collects all transitive dependency artifacts from the given direct dependency nodes.
+     * This method traverses the entire dependency tree and collects all artifacts at all levels.
+     *
+     * @param directDependencies the set of direct dependency nodes to traverse
+     * @return a list of all artifacts (direct + transitive)
+     */
+    private List<Artifact> getAllTransitiveDependencyArtifacts(final Set<DependencyNode> directDependencies) {
+        List<ArtifactWithPath> allArtifactsWithPaths = getAllTransitiveDependencyArtifactsWithPaths(directDependencies);
+
+        List<Artifact> artifacts = allArtifactsWithPaths.stream()
+            .map(ArtifactWithPath::getArtifact)
+            .collect(Collectors.toList());
+
+        getLog().debug(String.format("Collected %d total artifacts (direct + transitive) for shade analysis", artifacts.size()));
+
+        return artifacts;
+    }
+
+    /**
+     * Collects all transitive dependency artifacts with their dependency paths.
+     *
+     * @param directDependencies the set of direct dependency nodes to traverse
+     * @return a list of all artifacts with their paths (direct + transitive)
+     */
+    private List<ArtifactWithPath> getAllTransitiveDependencyArtifactsWithPaths(final Set<DependencyNode> directDependencies) {
+        Set<ArtifactWithPath> allArtifacts = new HashSet<>();
+
+        for (DependencyNode directDependency : directDependencies) {
+            collectAllArtifactsWithPathsFromNode(directDependency, new ArrayList<>(), allArtifacts);
+        }
+
+        getLog().debug(String.format("Collected %d total artifacts with paths for shade analysis", allArtifacts.size()));
+
+        return new ArrayList<>(allArtifacts);
+    }
+
+    /**
+     * Recursively collects all artifacts with their paths from a dependency node and its children.
+     *
+     * @param node        the dependency node to traverse
+     * @param currentPath the current dependency path (not including this node)
+     * @param collector   the set to collect artifacts with paths into
+     */
+    private void collectAllArtifactsWithPathsFromNode(final DependencyNode node,
+                                                      final List<Artifact> currentPath,
+                                                      final Set<ArtifactWithPath> collector) {
+        // Create the path including this node
+        List<Artifact> pathWithThisNode = new ArrayList<>(currentPath);
+        pathWithThisNode.add(node.getArtifact());
+
+        // Add the current node's artifact with its path
+        collector.add(new ArtifactWithPath(node.getArtifact(), pathWithThisNode));
+
+        // Recursively process all children
+        for (DependencyNode child : node.getChildren()) {
+            collectAllArtifactsWithPathsFromNode(child, pathWithThisNode, collector);
+        }
+    }
 }

src/main/java/com/github/streamshub/AggregateAlignmentReporterMojo.java

@@ -20,6 +20,7 @@
 package com.github.streamshub;
 
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 
 import org.apache.maven.artifact.resolver.filter.ArtifactFilter;
@@ -35,7 +36,9 @@ public class AggregateAlignmentReporterMojo extends AbstractAlignmentReporterMoj
     protected Set<DependencyNode> getDirectDependencies(final ArtifactFilter artifactFilter) throws MojoExecutionException {
         Set<DependencyNode> dependencies = new HashSet<>();
 
-        for (MavenProject reactorProject : reactorProjects) {
+        List<MavenProject> filteredProjects = filterModules(reactorProjects);
+
+        for (MavenProject reactorProject : filteredProjects) {
             dependencies.addAll(getDirectDependencies(reactorProject, artifactFilter));
         }
 

src/main/java/com/github/streamshub/ArtifactWithPath.java

@@ -0,0 +1,128 @@
+/*
+ * 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.
+ */
+
+package com.github.streamshub;
+
+import java.util.List;
+import java.util.Objects;
+
+import org.apache.maven.artifact.Artifact;
+
+/**
+ * Represents an artifact along with its dependency path.
+ * Used for tracking how transitive dependencies are reached in the dependency tree.
+ */
+public final class ArtifactWithPath {
+    private final Artifact artifact;
+    private final List<Artifact> dependencyPath;
+    private final boolean isDirect;
+
+    /**
+     * Creates an ArtifactWithPath for a direct dependency.
+     *
+     * @param artifact the artifact
+     */
+    public ArtifactWithPath(final Artifact artifactParam) {
+        this.artifact = artifactParam;
+        this.dependencyPath = List.of(artifactParam);
+        this.isDirect = true;
+    }
+
+    /**
+     * Creates an ArtifactWithPath for a transitive dependency.
+     *
+     * @param artifact       the artifact
+     * @param dependencyPath the full path from root to this artifact (including this artifact)
+     */
+    public ArtifactWithPath(final Artifact artifactParam, final List<Artifact> pathParam) {
+        this.artifact = artifactParam;
+        this.dependencyPath = List.copyOf(pathParam);
+        this.isDirect = pathParam.size() == 1;
+    }
+
+    public Artifact getArtifact() {
+        return artifact;
+    }
+
+    public List<Artifact> getDependencyPath() {
+        return dependencyPath;
+    }
+
+    public boolean isDirect() {
+        return isDirect;
+    }
+
+    public boolean isTransitive() {
+        return !isDirect;
+    }
+
+    /**
+     * Returns the root dependency (the direct dependency that brought this artifact in).
+     * For direct dependencies, returns the artifact itself.
+     */
+    public Artifact getRootDependency() {
+        return dependencyPath.get(0);
+    }
+
+    /**
+     * Formats the dependency path as a string in the format:
+     * "artifact <- parent <- ... <- root"
+     */
+    public String formatDependencyPath() {
+        if (isDirect) {
+            return artifact.toString() + " (direct)";
+        }
+
+        StringBuilder sb = new StringBuilder();
+
+        // Add the current artifact first
+        sb.append(artifact.toString());
+
+        // Add the path in reverse order (excluding the current artifact)
+        for (int i = dependencyPath.size() - 2; i >= 0; i--) {
+            sb.append(" <- ");
+            sb.append(dependencyPath.get(i)
+                .toString());
+        }
+
+        return sb.toString();
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        ArtifactWithPath that = (ArtifactWithPath) o;
+        return Objects.equals(artifact, that.artifact);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(artifact);
+    }
+
+    @Override
+    public String toString() {
+        return formatDependencyPath();
+    }
+}