Reduce memory usage when applying dependency management and exclusions

Closes gh-322

src/main/java/io/spring/gradle/dependencymanagement/internal/DependencyManagement.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2020 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -64,8 +64,6 @@ public class DependencyManagement {
 
     private final List<PomReference> importedBoms = new ArrayList<PomReference>();
 
-    private List<Pom> resolvedBoms = new ArrayList<Pom>();
-
     DependencyManagement(Project project, PomResolver pomResolver) {
         this(project, null, pomResolver);
     }
@@ -80,16 +78,6 @@ void importBom(Coordinates coordinates, PropertySource properties) {
         this.importedBoms.add(new PomReference(coordinates, properties));
     }
 
-    /**
-     * Returns the {@link Pom Poms} that have been imported.
-     *
-     * @return the imported poms
-     */
-    List<Pom> getImportedBoms() {
-        resolveIfNecessary();
-        return new ArrayList<Pom>(this.resolvedBoms);
-    }
-
     List<PomReference> getImportedBomReferences() {
         return this.importedBoms;
     }
@@ -180,9 +168,9 @@ private void resolve() {
 
         logger.debug("Preserving existing versions: {}", existingVersions);
 
-        this.resolvedBoms = this.pomResolver.resolvePoms(this.importedBoms, new ProjectPropertySource(this.project));
+        List<Pom> resolvedBoms = this.pomResolver.resolvePoms(this.importedBoms, new ProjectPropertySource(this.project));
 
-        for (Pom resolvedBom: this.resolvedBoms) {
+        for (Pom resolvedBom: resolvedBoms) {
             for (Dependency dependency : resolvedBom.getManagedDependencies()) {
                 if (isEmpty(dependency.getClassifier())) {
                     Coordinates coordinates = dependency.getCoordinates();

src/main/java/io/spring/gradle/dependencymanagement/internal/DependencyManagementConfigurationContainer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2016 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,8 +16,10 @@
 
 package io.spring.gradle.dependencymanagement.internal;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import org.gradle.api.Action;
-import org.gradle.api.DomainObjectCollection;
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.artifacts.ConfigurationContainer;
@@ -31,7 +33,7 @@
  */
 public class DependencyManagementConfigurationContainer {
 
-    private final DomainObjectCollection<Configuration> configurations;
+    private final List<Action<Configuration>> actions = new ArrayList<Action<Configuration>>();
 
     private final ConfigurationContainer delegate;
 
@@ -43,7 +45,6 @@ public class DependencyManagementConfigurationContainer {
      */
     public DependencyManagementConfigurationContainer(Project project) {
         this.delegate = project.getConfigurations();
-        this.configurations = project.container(Configuration.class);
     }
 
     /**
@@ -70,7 +71,9 @@ Configuration newConfiguration(ConfigurationConfigurer configurer,
         if (configurer != null) {
             configurer.configure(configuration);
         }
-        this.configurations.add(configuration);
+        for (Action<Configuration> action: this.actions) {
+            action.execute(configuration);
+        }
         return configuration;
     }
 
@@ -80,7 +83,7 @@ Configuration newConfiguration(ConfigurationConfigurer configurer,
      * @param action the action to apply
      */
     public void apply(Action<Configuration> action) {
-        this.configurations.all(action);
+        this.actions.add(action);
     }
 
     /**

src/main/java/io/spring/gradle/dependencymanagement/internal/Exclusions.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2020 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,6 +32,9 @@ class Exclusions {
     private final Map<String, Set<Exclusion>> exclusionsByDependency = new HashMap<String, Set<Exclusion>>();
 
     void add(String dependency, Collection<Exclusion> exclusionsForDependency) {
+        if (exclusionsForDependency.isEmpty()) {
+            return;
+        }
         Set<Exclusion> exclusions = this.exclusionsByDependency.get(dependency);
         if (exclusions == null) {
             exclusions = new HashSet<Exclusion>();

src/main/java/io/spring/gradle/dependencymanagement/internal/StandardPomDependencyManagementConfigurer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2020 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -140,9 +140,9 @@ private void configureBomImports(Node dependencies) {
         for (Dependency override: overrides) {
             appendDependencyNode(dependencies, override.getCoordinates(), override.getScope(), override.getType());
         }
-        List<Pom> importedBoms = this.dependencyManagement.getImportedBoms();
+        List<PomReference> importedBoms = this.dependencyManagement.getImportedBomReferences();
         Collections.reverse(importedBoms);
-        for (Pom resolvedBom: importedBoms) {
+        for (PomReference resolvedBom: importedBoms) {
             addImport(dependencies, resolvedBom);
         }
     }
@@ -175,7 +175,7 @@ private boolean differentVersions(Dependency dependency1, Dependency dependency2
         return !version1.equals(version2);
     }
 
-    private void addImport(Node dependencies, Pom importedBom) {
+    private void addImport(Node dependencies, PomReference importedBom) {
         appendDependencyNode(dependencies, importedBom.getCoordinates(), "import", "pom");
     }
 

src/main/java/io/spring/gradle/dependencymanagement/internal/maven/EffectiveModelBuilder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2020 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -48,33 +48,40 @@ final class EffectiveModelBuilder {
 
     private static final Logger logger = LoggerFactory.getLogger(EffectiveModelBuilder.class);
 
-    private final ModelCache modelCache = new InMemoryModelCache();
-
     private final ModelResolver modelResolver;
 
     EffectiveModelBuilder(Project project,
             DependencyManagementConfigurationContainer configurationContainer, PlatformCategoryAttributeConfigurer attributeConfigurer) {
         this.modelResolver = new ConfigurationModelResolver(project, configurationContainer, attributeConfigurer);
     }
 
-    Model buildModel(File pom, PropertySource properties) {
+    List<Model> buildModels(List<ModelInput> inputs) {
+        List<Model> models = new ArrayList<Model>();
+        InMemoryModelCache cache = new InMemoryModelCache();
+        for (ModelInput input: inputs) {
+            models.add(buildModel(input, cache));
+        }
+        return models;
+    }
+
+    private Model buildModel(ModelInput input, InMemoryModelCache cache) {
         DefaultModelBuildingRequest request = new DefaultModelBuildingRequest();
         request.setSystemProperties(System.getProperties());
-        request.setModelSource(new FileModelSource(pom));
+        request.setModelSource(new FileModelSource(input.pom));
         request.setModelResolver(this.modelResolver);
-        request.setModelCache(this.modelCache);
+        request.setModelCache(cache);
 
         try {
-            ModelBuildingResult result = createModelBuilder(properties).build(request);
+            ModelBuildingResult result = createModelBuilder(input.properties).build(request);
             List<ModelProblem> errors = extractErrors(result.getProblems());
             if (!errors.isEmpty()) {
-                reportErrors(errors, pom);
+                reportErrors(errors, input.pom);
             }
             return result.getEffectiveModel();
         }
         catch (ModelBuildingException ex) {
             logger.debug("Model building failed", ex);
-            reportErrors(extractErrors(ex.getProblems()), pom);
+            reportErrors(extractErrors(ex.getProblems()), input.pom);
             return ex.getResult().getEffectiveModel();
         }
     }
@@ -105,6 +112,22 @@ private DefaultModelBuilder createModelBuilder(PropertySource properties) {
         return modelBuilder;
     }
 
+    /**
+     * Input to a model building request.
+     */
+    static class ModelInput {
+
+        private final File pom;
+
+        private final PropertySource properties;
+
+        ModelInput(File pom, PropertySource properties) {
+            this.pom = pom;
+            this.properties = properties;
+        }
+
+    }
+
     private static final class InMemoryModelCache implements ModelCache {
 
         private final Map<Key, Object> cache = new ConcurrentHashMap<Key, Object>();

src/main/java/io/spring/gradle/dependencymanagement/internal/maven/MavenPomResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2020 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,6 @@
 
 package io.spring.gradle.dependencymanagement.internal.maven;
 
-import java.io.File;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -36,6 +35,7 @@
 
 import io.spring.gradle.dependencymanagement.internal.DependencyManagementConfigurationContainer;
 import io.spring.gradle.dependencymanagement.internal.Exclusion;
+import io.spring.gradle.dependencymanagement.internal.maven.EffectiveModelBuilder.ModelInput;
 import io.spring.gradle.dependencymanagement.internal.pom.Coordinates;
 import io.spring.gradle.dependencymanagement.internal.pom.Dependency;
 import io.spring.gradle.dependencymanagement.internal.pom.Pom;
@@ -120,22 +120,26 @@ private List<Pom> createPoms(Set<ResolvedArtifact> resolvedArtifacts, List<PomRe
             referencesById.put(createKey(pomReference.getCoordinates().getGroupId(),
                     pomReference.getCoordinates().getArtifactId()), pomReference);
         }
-        List<Pom> resolvedPoms = new ArrayList<Pom>();
+        List<ModelInput> modelInputs = new ArrayList<ModelInput>();
         for (ResolvedArtifact resolvedArtifact: resolvedArtifacts) {
             ModuleVersionIdentifier id = resolvedArtifact.getModuleVersion().getId();
             PomReference reference = referencesById.get(createKey(id.getGroup(), id.getName()));
             CompositePropertySource allProperties = new CompositePropertySource(reference.getProperties(), properties);
-            resolvedPoms.add(createPom(resolvedArtifact.getFile(), allProperties));
+            modelInputs.add(new ModelInput(resolvedArtifact.getFile(), allProperties));
         }
-        return resolvedPoms;
+        return createPoms(modelInputs);
     }
 
-    private Pom createPom(File file, PropertySource properties) {
-        Model effectiveModel = this.effectiveModelBuilder.buildModel(file, properties);
-        Coordinates coordinates = new Coordinates(effectiveModel.getGroupId(), effectiveModel.getArtifactId(),
-                effectiveModel.getVersion());
-        return new Pom(coordinates, getManagedDependencies(effectiveModel), getDependencies(effectiveModel),
-                asMap(effectiveModel.getProperties()));
+    private List<Pom> createPoms(List<ModelInput> inputs) {
+        List<Model> effectiveModels = this.effectiveModelBuilder.buildModels(inputs);
+        List<Pom> poms = new ArrayList<Pom>(effectiveModels.size());
+        for (Model effectiveModel: effectiveModels) {
+            Coordinates coordinates = new Coordinates(effectiveModel.getGroupId(), effectiveModel.getArtifactId(),
+                    effectiveModel.getVersion());
+            poms.add(new Pom(coordinates, getManagedDependencies(effectiveModel), getDependencies(effectiveModel),
+                    asMap(effectiveModel.getProperties())));
+        }
+        return poms;
     }
 
     private List<Dependency> getManagedDependencies(Model model) {