[MNG-8239] Add missing ModelCacheFactory (#1728)

api/maven-api-core/src/main/java/org/apache/maven/api/services/ModelBuilderRequest.java

@@ -146,9 +146,6 @@ public interface ModelBuilderRequest {
     @Nonnull
     ModelRepositoryHolder getModelRepositoryHolder();
 
-    @Nullable
-    ModelCache getModelCache();
-
     @Nullable
     Object getListener();
 
@@ -210,7 +207,6 @@ public interface ModelBuilderRequest {
         Map<String, String> userProperties;
         ModelResolver modelResolver;
         ModelRepositoryHolder modelRepositoryHolder;
-        ModelCache modelCache;
         Object listener;
         ModelBuilderResult interimResult;
         ModelTransformerContextBuilder transformerContextBuilder;
@@ -233,7 +229,6 @@ public interface ModelBuilderRequest {
             this.userProperties = request.getUserProperties();
             this.modelResolver = request.getModelResolver();
             this.modelRepositoryHolder = request.getModelRepositoryHolder();
-            this.modelCache = request.getModelCache();
             this.listener = request.getListener();
             this.interimResult = request.getInterimResult();
             this.transformerContextBuilder = request.getTransformerContextBuilder();
@@ -310,11 +305,6 @@ public interface ModelBuilderRequest {
             return this;
         }
 
-        public ModelBuilderRequestBuilder modelCache(ModelCache modelCache) {
-            this.modelCache = modelCache;
-            return this;
-        }
-
         public ModelBuilderRequestBuilder listener(Object listener) {
             this.listener = listener;
             return this;
@@ -352,7 +342,6 @@ public interface ModelBuilderRequest {
                     userProperties,
                     modelResolver,
                     modelRepositoryHolder,
-                    modelCache,
                     listener,
                     interimResult,
                     transformerContextBuilder,
@@ -373,7 +362,6 @@ public interface ModelBuilderRequest {
             private final Map<String, String> userProperties;
             private final ModelResolver modelResolver;
             private final ModelRepositoryHolder modelRepositoryHolder;
-            private final ModelCache modelCache;
             private final Object listener;
             private final ModelBuilderResult interimResult;
             private final ModelTransformerContextBuilder transformerContextBuilder;
@@ -395,7 +383,6 @@ public interface ModelBuilderRequest {
                     Map<String, String> userProperties,
                     ModelResolver modelResolver,
                     ModelRepositoryHolder modelRepositoryHolder,
-                    ModelCache modelCache,
                     Object listener,
                     ModelBuilderResult interimResult,
                     ModelTransformerContextBuilder transformerContextBuilder,
@@ -415,7 +402,6 @@ public interface ModelBuilderRequest {
                 this.userProperties = userProperties != null ? Map.copyOf(userProperties) : session.getUserProperties();
                 this.modelResolver = modelResolver;
                 this.modelRepositoryHolder = modelRepositoryHolder;
-                this.modelCache = modelCache;
                 this.listener = listener;
                 this.interimResult = interimResult;
                 this.transformerContextBuilder = transformerContextBuilder;
@@ -487,11 +473,6 @@ public interface ModelBuilderRequest {
                 return modelRepositoryHolder;
             }
 
-            @Override
-            public ModelCache getModelCache() {
-                return modelCache;
-            }
-
             public Object getListener() {
                 return listener;
             }

api/maven-api-core/src/main/java/org/apache/maven/api/services/PathSource.java

@@ -72,7 +72,7 @@ class PathSource implements ModelSource {
 
     @Override
     public boolean equals(Object o) {
-        return this == o || o instanceof PathSource ps && Objects.equals(path, ps.path);
+        return this == o || o.getClass() == getClass() && Objects.equals(path, ((PathSource) o).path);
     }
 
     @Override

maven-api-impl/src/main/java/org/apache/maven/api/services/model/ModelCache.java

@@ -16,21 +16,33 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.apache.maven.api.services;
+package org.apache.maven.api.services.model;
 
 import java.util.function.Supplier;
 
+import org.apache.maven.api.annotations.Experimental;
+import org.apache.maven.api.annotations.ThreadSafe;
+import org.apache.maven.api.services.Source;
+
 /**
  * Caches auxiliary data used during model building like already processed raw/effective models. The data in the cache
  * is meant for exclusive consumption by the model builder and is opaque to the cache implementation. The cache key is
- * formed by a combination of group id, artifact id, version and tag. The first three components generally refer to the
+ * formed by a combination of group id, artifact id, version and tag, or by the pom path on the filesystem and tag.
- * identity of a model. The tag allows for further classification of the associated data on the sole discretion of the
+ * The tag allows for further classification of the associated data on the sole discretion of the model builder.
- * model builder.
+ * The cache is expected to be valid through the lifetime of the session, so the model builder is not allowed to
+ * store data which may change during the session, especially effective models which may be different if the
+ * user properties or activate profiles change between two invocations of the model builder.
+ * The cache implementation is expected to be thread-safe.
  *
+ * @since 4.0.0
  */
+@Experimental
+@ThreadSafe
 public interface ModelCache {
 
     <T> T computeIfAbsent(String groupId, String artifactId, String version, String tag, Supplier<T> data);
 
     <T> T computeIfAbsent(Source path, String tag, Supplier<T> data);
+
+    void clear();
 }

maven-api-impl/src/main/java/org/apache/maven/api/services/model/ModelCacheFactory.java

@@ -0,0 +1,41 @@
+/*
+ * 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 org.apache.maven.api.services.model;
+
+import org.apache.maven.api.annotations.Experimental;
+import org.apache.maven.api.annotations.Nonnull;
+
+/**
+ * Factory for creating model caches.
+ * <p>
+ * The model cache is meant for exclusive consumption by the model builder and is opaque to the cache implementation.
+ * The cache is created once per session and is valid through the lifetime of the session.
+ * <p>
+ * The cache implementation could be annotated with {@code SessionScoped} to be created once per session, but
+ * this would make tests more complicated to write as they would all need to enter the session scope.
+ * This is similar to the {@code CIFriendlyVersionModelTransformer}.
+ *
+ * @since 4.0.0
+ */
+@Experimental
+public interface ModelCacheFactory {
+
+    @Nonnull
+    ModelCache newInstance();
+}

maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelBuilder.java

@@ -42,6 +42,7 @@ import java.util.function.UnaryOperator;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import org.apache.maven.api.SessionData;
 import org.apache.maven.api.Type;
 import org.apache.maven.api.VersionRange;
 import org.apache.maven.api.annotations.Nullable;
@@ -67,7 +68,6 @@ import org.apache.maven.api.services.ModelBuilder;
 import org.apache.maven.api.services.ModelBuilderException;
 import org.apache.maven.api.services.ModelBuilderRequest;
 import org.apache.maven.api.services.ModelBuilderResult;
-import org.apache.maven.api.services.ModelCache;
 import org.apache.maven.api.services.ModelProblem;
 import org.apache.maven.api.services.ModelProblemCollector;
 import org.apache.maven.api.services.ModelResolver;
@@ -86,6 +86,8 @@ import org.apache.maven.api.services.model.InheritanceAssembler;
 import org.apache.maven.api.services.model.LifecycleBindingsInjector;
 import org.apache.maven.api.services.model.ModelBuildingEvent;
 import org.apache.maven.api.services.model.ModelBuildingListener;
+import org.apache.maven.api.services.model.ModelCache;
+import org.apache.maven.api.services.model.ModelCacheFactory;
 import org.apache.maven.api.services.model.ModelInterpolator;
 import org.apache.maven.api.services.model.ModelNormalizer;
 import org.apache.maven.api.services.model.ModelPathTranslator;
@@ -101,7 +103,6 @@ import org.apache.maven.api.services.model.ProfileSelector;
 import org.apache.maven.api.services.model.WorkspaceModelResolver;
 import org.apache.maven.api.services.xml.XmlReaderException;
 import org.apache.maven.api.services.xml.XmlReaderRequest;
-import org.apache.maven.internal.impl.resolver.DefaultModelCache;
 import org.apache.maven.internal.impl.resolver.DefaultModelRepositoryHolder;
 import org.apache.maven.internal.impl.resolver.DefaultModelResolver;
 import org.apache.maven.model.v4.MavenTransformer;
@@ -145,6 +146,7 @@ public class DefaultModelBuilder implements ModelBuilder {
     private final ModelTransformer transformer;
     private final ModelVersionParser versionParser;
     private final List<org.apache.maven.api.spi.ModelTransformer> transformers;
+    private final ModelCacheFactory modelCacheFactory;
 
     @SuppressWarnings("checkstyle:ParameterNumber")
     @Inject
@@ -167,7 +169,8 @@ public class DefaultModelBuilder implements ModelBuilder {
             ProfileActivationFilePathInterpolator profileActivationFilePathInterpolator,
             ModelTransformer transformer,
             ModelVersionParser versionParser,
-            List<org.apache.maven.api.spi.ModelTransformer> transformers) {
+            List<org.apache.maven.api.spi.ModelTransformer> transformers,
+            ModelCacheFactory modelCacheFactory) {
         this.modelProcessor = modelProcessor;
         this.modelValidator = modelValidator;
         this.modelNormalizer = modelNormalizer;
@@ -187,6 +190,7 @@ public class DefaultModelBuilder implements ModelBuilder {
         this.transformer = transformer;
         this.versionParser = versionParser;
         this.transformers = transformers;
+        this.modelCacheFactory = modelCacheFactory;
     }
 
     @Override
@@ -206,9 +210,6 @@ public class DefaultModelBuilder implements ModelBuilder {
 
     private static ModelBuilderRequest fillRequestDefaults(ModelBuilderRequest request) {
         ModelBuilderRequest.ModelBuilderRequestBuilder builder = ModelBuilderRequest.builder(request);
-        if (request.getModelCache() == null) {
-            builder.modelCache(new DefaultModelCache());
-        }
         if (request.getModelRepositoryHolder() == null) {
             builder.modelRepositoryHolder(new DefaultModelRepositoryHolder(
                     request.getSession(),
@@ -1465,7 +1466,6 @@ public class DefaultModelBuilder implements ModelBuilder {
                         .userProperties(request.getUserProperties())
                         .source(importSource)
                         .modelResolver(modelResolver)
-                        .modelCache(request.getModelCache())
                         .modelRepositoryHolder(
                                 request.getModelRepositoryHolder().copy())
                         .twoPhaseBuilding(false)
@@ -1486,21 +1486,11 @@ public class DefaultModelBuilder implements ModelBuilder {
 
     private static <T> T cache(
             ModelCache cache, String groupId, String artifactId, String version, String tag, Callable<T> supplier) {
-        Supplier<T> s = asSupplier(supplier);
+        return cache.computeIfAbsent(groupId, artifactId, version, tag, asSupplier(supplier));
-        if (cache == null) {
-            return s.get();
-        } else {
-            return cache.computeIfAbsent(groupId, artifactId, version, tag, s);
-        }
     }
 
     private static <T> T cache(ModelCache cache, Source source, String tag, Callable<T> supplier) {
-        Supplier<T> s = asSupplier(supplier);
+        return cache.computeIfAbsent(source, tag, asSupplier(supplier));
-        if (cache == null) {
-            return s.get();
-        } else {
-            return cache.computeIfAbsent(source, tag, s);
-        }
     }
 
     private static <T> Supplier<T> asSupplier(Callable<T> supplier) {
@@ -1557,8 +1547,10 @@ public class DefaultModelBuilder implements ModelBuilder {
         return modelProcessor;
     }
 
-    private static ModelCache getModelCache(ModelBuilderRequest request) {
+    private ModelCache getModelCache(ModelBuilderRequest request) {
-        return request.getModelCache();
+        return request.getSession()
+                .getData()
+                .computeIfAbsent(SessionData.key(ModelCache.class), modelCacheFactory::newInstance);
     }
 
     private static ModelBuildingListener getModelBuildingListener(ModelBuilderRequest request) {

maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelCache.java

@@ -16,17 +16,15 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.apache.maven.internal.impl.resolver;
+package org.apache.maven.internal.impl.model;
 
 import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.function.Supplier;
 
-import org.apache.maven.api.services.ModelCache;
 import org.apache.maven.api.services.Source;
-import org.eclipse.aether.RepositoryCache;
+import org.apache.maven.api.services.model.ModelCache;
-import org.eclipse.aether.RepositorySystemSession;
 
 import static java.util.Objects.requireNonNull;
 
@@ -35,25 +33,6 @@ import static java.util.Objects.requireNonNull;
  *
  */
 public class DefaultModelCache implements ModelCache {
-    private static final String KEY = DefaultModelCache.class.getName();
-
-    @SuppressWarnings("unchecked")
-    public static ModelCache newInstance(RepositorySystemSession session, boolean anew) {
-        ConcurrentHashMap<Object, Supplier<?>> cache;
-        RepositoryCache repositoryCache = session != null ? session.getCache() : null;
-        if (repositoryCache == null) {
-            return new DefaultModelCache(new ConcurrentHashMap<>());
-        } else {
-            if (anew) {
-                cache = new ConcurrentHashMap<>();
-                repositoryCache.put(session, KEY, cache);
-            } else {
-                cache = (ConcurrentHashMap<Object, Supplier<?>>)
-                        repositoryCache.computeIfAbsent(session, KEY, ConcurrentHashMap::new);
-            }
-            return new DefaultModelCache(cache);
-        }
-    }
 
     private final ConcurrentMap<Object, Supplier<?>> cache;
 
@@ -77,6 +56,11 @@ public class DefaultModelCache implements ModelCache {
         return (T) computeIfAbsent(new SourceCacheKey(path, tag), data);
     }
 
+    @Override
+    public void clear() {
+        cache.clear();
+    }
+
     protected Object computeIfAbsent(Object key, Supplier<?> data) {
         return cache.computeIfAbsent(key, k -> new CachingSupplier<>(data)).get();
     }

maven-api-impl/src/main/java/org/apache/maven/internal/impl/model/DefaultModelCacheFactory.java

@@ -0,0 +1,33 @@
+/*
+ * 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 org.apache.maven.internal.impl.model;
+
+import org.apache.maven.api.di.Named;
+import org.apache.maven.api.di.Singleton;
+import org.apache.maven.api.services.model.ModelCache;
+import org.apache.maven.api.services.model.ModelCacheFactory;
+
+@Named
+@Singleton
+public class DefaultModelCacheFactory implements ModelCacheFactory {
+    @Override
+    public ModelCache newInstance() {
+        return new DefaultModelCache();
+    }
+}

maven-api-impl/src/main/java/org/apache/maven/internal/impl/resolver/DefaultArtifactDescriptorReader.java

@@ -218,7 +218,6 @@ public class DefaultArtifactDescriptorReader implements ArtifactDescriptorReader
                         .userProperties(Map.of())
                         .modelResolver(modelResolver)
                         .modelRepositoryHolder(modelRepositoryHolder)
-                        .modelCache(DefaultModelCache.newInstance(session, false))
                         .repositories(repositories)
                         .build();
 

maven-api-impl/src/main/java/org/apache/maven/internal/impl/resolver/DefaultModelResolver.java

@@ -23,6 +23,7 @@ import java.io.InputStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.List;
+import java.util.Objects;
 import java.util.function.Consumer;
 import java.util.stream.Collectors;
 
@@ -86,32 +87,7 @@ public class DefaultModelResolver implements ModelResolver {
                     session.createArtifactCoordinates(groupId, artifactId, newVersion, "pom"), repositories);
             Path path = resolved.getPath();
             String location = groupId + ":" + artifactId + ":" + newVersion;
-            return new ModelSource() {
+            return new ResolverModelSource(path, location);
-                @Override
-                public ModelSource resolve(ModelLocator modelLocator, String relative) {
-                    return null;
-                }
-
-                @Override
-                public Path getPath() {
-                    return null;
-                }
-
-                @Override
-                public InputStream openStream() throws IOException {
-                    return Files.newInputStream(path);
-                }
-
-                @Override
-                public String getLocation() {
-                    return location;
-                }
-
-                @Override
-                public Source resolve(String relative) {
-                    return null;
-                }
-            };
         } catch (VersionRangeResolverException | ArtifactResolverException e) {
             throw new ModelResolverException(
                     e.getMessage() + " (remote repositories: "
@@ -124,4 +100,56 @@ public class DefaultModelResolver implements ModelResolver {
                     e);
         }
     }
+
+    private static class ResolverModelSource implements ModelSource {
+        private final Path path;
+        private final String location;
+
+        ResolverModelSource(Path path, String location) {
+            this.path = path;
+            this.location = location;
+        }
+
+        @Override
+        public ModelSource resolve(ModelLocator modelLocator, String relative) {
+            return null;
+        }
+
+        @Override
+        public Path getPath() {
+            return null;
+        }
+
+        @Override
+        public InputStream openStream() throws IOException {
+            return Files.newInputStream(path);
+        }
+
+        @Override
+        public String getLocation() {
+            return location;
+        }
+
+        @Override
+        public Source resolve(String relative) {
+            return null;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+            ResolverModelSource that = (ResolverModelSource) o;
+            return Objects.equals(path, that.path) && Objects.equals(location, that.location);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(path, location);
+        }
+    }
 }

maven-api-impl/src/test/java/org/apache/maven/internal/impl/standalone/RepositorySystemSupplier.java

@@ -37,6 +37,7 @@ import org.apache.maven.internal.impl.model.DefaultDependencyManagementImporter;
 import org.apache.maven.internal.impl.model.DefaultDependencyManagementInjector;
 import org.apache.maven.internal.impl.model.DefaultInheritanceAssembler;
 import org.apache.maven.internal.impl.model.DefaultModelBuilder;
+import org.apache.maven.internal.impl.model.DefaultModelCacheFactory;
 import org.apache.maven.internal.impl.model.DefaultModelInterpolator;
 import org.apache.maven.internal.impl.model.DefaultModelNormalizer;
 import org.apache.maven.internal.impl.model.DefaultModelPathTranslator;
@@ -1060,7 +1061,8 @@ public class RepositorySystemSupplier implements Supplier<RepositorySystem> {
                 new ProfileActivationFilePathInterpolator(new DefaultPathTranslator(), new DefaultRootLocator()),
                 new BuildModelTransformer(),
                 new DefaultModelVersionParser(getVersionScheme()),
-                List.of());
+                List.of(),
+                new DefaultModelCacheFactory());
     }
 
     private RepositorySystem repositorySystem;

maven-core/src/main/java/org/apache/maven/internal/transformation/impl/DefaultConsumerPomBuilder.java

@@ -26,7 +26,6 @@ import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
-import java.util.Map;
 import java.util.stream.Collectors;
 
 import org.apache.maven.api.SessionData;
@@ -49,6 +48,7 @@ import org.apache.maven.api.services.model.DependencyManagementImporter;
 import org.apache.maven.api.services.model.DependencyManagementInjector;
 import org.apache.maven.api.services.model.InheritanceAssembler;
 import org.apache.maven.api.services.model.LifecycleBindingsInjector;
+import org.apache.maven.api.services.model.ModelCacheFactory;
 import org.apache.maven.api.services.model.ModelInterpolator;
 import org.apache.maven.api.services.model.ModelNormalizer;
 import org.apache.maven.api.services.model.ModelPathTranslator;
@@ -65,7 +65,6 @@ import org.apache.maven.internal.impl.InternalSession;
 import org.apache.maven.internal.impl.model.DefaultModelBuilder;
 import org.apache.maven.internal.impl.model.DefaultProfileSelector;
 import org.apache.maven.internal.impl.model.ProfileActivationFilePathInterpolator;
-import org.apache.maven.internal.impl.resolver.DefaultModelCache;
 import org.apache.maven.model.v4.MavenModelVersion;
 import org.apache.maven.project.MavenProject;
 import org.eclipse.aether.RepositorySystem;
@@ -141,6 +140,9 @@ class DefaultConsumerPomBuilder implements ConsumerPomBuilder {
     @Inject
     private List<org.apache.maven.api.spi.ModelTransformer> transformers;
 
+    @Inject
+    private ModelCacheFactory modelCacheFactory;
+
     Logger logger = LoggerFactory.getLogger(getClass());
 
     @Override
@@ -197,7 +199,8 @@ class DefaultConsumerPomBuilder implements ConsumerPomBuilder {
                 profileActivationFilePathInterpolator,
                 modelTransformer,
                 versionParser,
-                transformers);
+                transformers,
+                modelCacheFactory);
         InternalSession iSession = InternalSession.from(session);
         ModelBuilderRequest.ModelBuilderRequestBuilder request = ModelBuilderRequest.builder();
         request.projectBuild(true);
@@ -209,19 +212,6 @@ class DefaultConsumerPomBuilder implements ConsumerPomBuilder {
         request.transformerContextBuilder(modelBuilder.newTransformerContextBuilder());
         request.systemProperties(session.getSystemProperties());
         request.userProperties(session.getUserProperties());
-        request.modelCache(DefaultModelCache.newInstance(session, false));
-        if (session.getCache() != null) {
-            Map<?, ?> map = (Map) session.getCache().get(session, DefaultModelCache.class.getName());
-            List<String> paths = map.keySet().stream()
-                    .map(Object::toString)
-                    .filter(s -> s.startsWith("SourceCacheKey"))
-                    .map(s -> s.substring("SourceCacheKey[location=".length(), s.indexOf(", tag")))
-                    .sorted()
-                    .distinct()
-                    .toList();
-            logger.debug("ModelCache contains " + paths.size());
-            paths.forEach(s -> logger.debug("    " + s));
-        }
         return modelBuilder.build(request.build());
     }
 

maven-core/src/main/java/org/apache/maven/project/DefaultProjectBuilder.java

@@ -37,6 +37,7 @@ import java.util.HashSet;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Properties;
 import java.util.Set;
 import java.util.concurrent.Callable;
@@ -75,7 +76,6 @@ import org.apache.maven.api.services.ModelBuilder;
 import org.apache.maven.api.services.ModelBuilderException;
 import org.apache.maven.api.services.ModelBuilderRequest;
 import org.apache.maven.api.services.ModelBuilderResult;
-import org.apache.maven.api.services.ModelCache;
 import org.apache.maven.api.services.ModelProblem;
 import org.apache.maven.api.services.ModelResolver;
 import org.apache.maven.api.services.ModelResolverException;
@@ -91,7 +91,6 @@ import org.apache.maven.artifact.InvalidRepositoryException;
 import org.apache.maven.artifact.repository.ArtifactRepository;
 import org.apache.maven.bridge.MavenRepositorySystem;
 import org.apache.maven.internal.impl.InternalSession;
-import org.apache.maven.internal.impl.resolver.DefaultModelCache;
 import org.apache.maven.internal.impl.resolver.DefaultModelRepositoryHolder;
 import org.apache.maven.model.building.DefaultModelProblem;
 import org.apache.maven.model.building.FileModelSource;
@@ -181,56 +180,7 @@ public class DefaultProjectBuilder implements ProjectBuilder {
         if (modelSource instanceof FileModelSource fms) {
             return ModelSource.fromPath(fms.getPath());
         } else {
-            return new ModelSource() {
+            return new WrapModelSource(modelSource);
-                @Override
-                public ModelSource resolve(ModelLocator modelLocator, String relative) {
-                    if (modelSource instanceof ModelSource3 ms) {
-                        return toSource(ms.getRelatedSource(
-                                new org.apache.maven.model.locator.ModelLocator() {
-                                    @Override
-                                    public File locatePom(File projectDirectory) {
-                                        return null;
-                                    }
-
-                                    @Override
-                                    public Path locatePom(Path projectDirectory) {
-                                        return null;
-                                    }
-
-                                    @Override
-                                    public Path locateExistingPom(Path project) {
-                                        return modelLocator.locateExistingPom(project);
-                                    }
-                                },
-                                relative));
-                    }
-                    return null;
-                }
-
-                @Override
-                public Path getPath() {
-                    return null;
-                }
-
-                @Override
-                public InputStream openStream() throws IOException {
-                    return modelSource.getInputStream();
-                }
-
-                @Override
-                public String getLocation() {
-                    return modelSource.getLocation();
-                }
-
-                @Override
-                public Source resolve(String relative) {
-                    if (modelSource instanceof ModelSource2 ms) {
-                        return toSource(ms.getRelatedSource(relative));
-                    } else {
-                        return null;
-                    }
-                }
-            };
         }
     }
 
@@ -301,6 +251,132 @@ public class DefaultProjectBuilder implements ProjectBuilder {
         }
     }
 
+    private static class StubModelSource implements ModelSource {
+        private final String xml;
+        private final Artifact artifact;
+
+        StubModelSource(String xml, Artifact artifact) {
+            this.xml = xml;
+            this.artifact = artifact;
+        }
+
+        @Override
+        public ModelSource resolve(ModelLocator modelLocator, String relative) {
+            return null;
+        }
+
+        @Override
+        public Path getPath() {
+            return null;
+        }
+
+        @Override
+        public InputStream openStream() throws IOException {
+            return new ByteArrayInputStream(xml.getBytes(StandardCharsets.UTF_8));
+        }
+
+        @Override
+        public String getLocation() {
+            return artifact.getId();
+        }
+
+        @Override
+        public Source resolve(String relative) {
+            return null;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+            StubModelSource that = (StubModelSource) o;
+            return Objects.equals(xml, that.xml) && Objects.equals(artifact, that.artifact);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(xml, artifact);
+        }
+    }
+
+    private static class WrapModelSource implements ModelSource {
+        private final org.apache.maven.model.building.ModelSource modelSource;
+
+        WrapModelSource(org.apache.maven.model.building.ModelSource modelSource) {
+            this.modelSource = modelSource;
+        }
+
+        @Override
+        public ModelSource resolve(ModelLocator modelLocator, String relative) {
+            if (modelSource instanceof ModelSource3 ms) {
+                return toSource(ms.getRelatedSource(
+                        new org.apache.maven.model.locator.ModelLocator() {
+                            @Override
+                            public File locatePom(File projectDirectory) {
+                                return null;
+                            }
+
+                            @Override
+                            public Path locatePom(Path projectDirectory) {
+                                return null;
+                            }
+
+                            @Override
+                            public Path locateExistingPom(Path project) {
+                                return modelLocator.locateExistingPom(project);
+                            }
+                        },
+                        relative));
+            }
+            return null;
+        }
+
+        @Override
+        public Path getPath() {
+            return null;
+        }
+
+        @Override
+        public InputStream openStream() throws IOException {
+            return modelSource.getInputStream();
+        }
+
+        @Override
+        public String getLocation() {
+            return modelSource.getLocation();
+        }
+
+        @Override
+        public Source resolve(String relative) {
+            if (modelSource instanceof ModelSource2 ms) {
+                return toSource(ms.getRelatedSource(relative));
+            } else {
+                return null;
+            }
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+            WrapModelSource that = (WrapModelSource) o;
+            return Objects.equals(modelSource, that.modelSource);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hashCode(modelSource);
+        }
+    }
+
     class BuildSession implements AutoCloseable {
         private final ProjectBuildingRequest request;
         private final RepositorySystemSession session;
@@ -309,7 +385,6 @@ public class DefaultProjectBuilder implements ProjectBuilder {
         private final ConcurrentMap<String, Object> parentCache;
         private final ModelTransformerContextBuilder transformerContextBuilder;
         private final ExecutorService executor;
-        private final ModelCache modelCache;
         private final ModelResolver modelResolver;
         private final Map<String, String> ciFriendlyVersions = new ConcurrentHashMap<>();
 
@@ -328,7 +403,6 @@ public class DefaultProjectBuilder implements ProjectBuilder {
                 this.transformerContextBuilder = null;
             }
             this.parentCache = new ConcurrentHashMap<>();
-            this.modelCache = DefaultModelCache.newInstance(session, true);
             this.modelResolver = new ModelResolverWrapper() {
                 @Override
                 protected org.apache.maven.model.resolution.ModelResolver getResolver(
@@ -1131,7 +1205,6 @@ public class DefaultProjectBuilder implements ProjectBuilder {
                             .map(internalSession::getRemoteRepository)
                             .toList());
             modelBuildingRequest.modelRepositoryHolder(holder);
-            modelBuildingRequest.modelCache(modelCache);
             modelBuildingRequest.transformerContextBuilder(transformerContextBuilder);
             modelBuildingRequest.repositories(request.getRemoteRepositories().stream()
                     .map(r -> internalSession.getRemoteRepository(RepositoryUtils.toRepo(r)))
@@ -1204,32 +1277,9 @@ public class DefaultProjectBuilder implements ProjectBuilder {
         buffer.append("<packaging>").append(artifact.getType()).append("</packaging>");
         buffer.append("</project>");
 
-        return new ModelSource() {
+        String xml = buffer.toString();
-            @Override
-            public ModelSource resolve(ModelLocator modelLocator, String relative) {
-                return null;
-            }
 
-            @Override
+        return new StubModelSource(xml, artifact);
-            public Path getPath() {
-                return null;
-            }
-
-            @Override
-            public InputStream openStream() throws IOException {
-                return new ByteArrayInputStream(buffer.toString().getBytes(StandardCharsets.UTF_8));
-            }
-
-            @Override
-            public String getLocation() {
-                return artifact.getId();
-            }
-
-            @Override
-            public Source resolve(String relative) {
-                return null;
-            }
-        };
     }
 
     private static String inheritedGroupId(final ModelBuilderResult result, final int modelIndex) {

maven-core/src/test/java/org/apache/maven/project/DefaultMavenProjectBuilderTest.java

@@ -25,8 +25,11 @@ import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
 import java.util.List;
 
+import org.apache.maven.api.SessionData;
+import org.apache.maven.api.services.model.ModelCache;
 import org.apache.maven.artifact.Artifact;
 import org.apache.maven.artifact.repository.ArtifactRepository;
+import org.apache.maven.internal.impl.InternalSession;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
@@ -329,6 +332,12 @@ class DefaultMavenProjectBuilderTest extends AbstractMavenProjectTestCase {
                 projectBuilder.build(pom.toFile(), buildingRequest).getProject();
         assertThat(project.getName(), is("aid")); // inherited from artifactId
 
+        // clear the cache
+        InternalSession.from(buildingRequest.getRepositorySession())
+                .getData()
+                .get(SessionData.key(ModelCache.class))
+                .clear();
+
         try (InputStream pomResource =
                 DefaultMavenProjectBuilderTest.class.getResourceAsStream("/projects/reread/pom2.xml")) {
             Files.copy(pomResource, pom, StandardCopyOption.REPLACE_EXISTING);

maven-core/src/test/java/org/apache/maven/project/ProjectBuilderTest.java

@@ -29,6 +29,8 @@ import java.util.Properties;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import org.apache.maven.AbstractCoreMavenComponentTestCase;
+import org.apache.maven.api.SessionData;
+import org.apache.maven.api.services.model.ModelCache;
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.model.Dependency;
 import org.apache.maven.model.InputLocation;
@@ -179,6 +181,12 @@ class ProjectBuilderTest extends AbstractCoreMavenComponentTestCase {
         File child = new File(tempDir.toFile(), "child/pom.xml");
         // build project once
         projectBuilder.build(child, configuration);
+        // clear the cache
+        mavenSession
+                .getSession()
+                .getData()
+                .get(SessionData.key(ModelCache.class))
+                .clear();
         // modify parent
         File parent = new File(tempDir.toFile(), "pom.xml");
         String parentContent = new String(Files.readAllBytes(parent.toPath()), StandardCharsets.UTF_8);

maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/MavenRepositorySystemSupplier.java

@@ -37,6 +37,7 @@ import org.apache.maven.internal.impl.model.DefaultDependencyManagementImporter;
 import org.apache.maven.internal.impl.model.DefaultDependencyManagementInjector;
 import org.apache.maven.internal.impl.model.DefaultInheritanceAssembler;
 import org.apache.maven.internal.impl.model.DefaultModelBuilder;
+import org.apache.maven.internal.impl.model.DefaultModelCacheFactory;
 import org.apache.maven.internal.impl.model.DefaultModelInterpolator;
 import org.apache.maven.internal.impl.model.DefaultModelNormalizer;
 import org.apache.maven.internal.impl.model.DefaultModelPathTranslator;
@@ -1062,7 +1063,8 @@ public class MavenRepositorySystemSupplier implements Supplier<RepositorySystem>
                 new ProfileActivationFilePathInterpolator(new DefaultPathTranslator(), new DefaultRootLocator()),
                 new BuildModelTransformer(),
                 new DefaultModelVersionParser(getVersionScheme()),
-                List.of());
+                List.of(),
+                new DefaultModelCacheFactory());
     }
 
     private RepositorySystem repositorySystem;