[MNG-8239] Missing ModelCacheFactory and introduce ModelBuilderSession

Author: gnodet

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

@@ -134,9 +134,6 @@ enum RepositoryMerging {
     @Nonnull
     RepositoryMerging getRepositoryMerging();
 
-    @Nullable
-    ModelCache getModelCache();
-
     @Nullable
     Object getListener();
 
@@ -194,7 +191,6 @@ class ModelBuilderRequestBuilder {
         ModelResolver modelResolver;
         Object modelRepositoryHolder;
         RepositoryMerging repositoryMerging;
-        ModelCache modelCache;
         Object listener;
         ModelBuilderResult interimResult;
         List<RemoteRepository> repositories;
@@ -215,7 +211,6 @@ class ModelBuilderRequestBuilder {
             this.modelResolver = request.getModelResolver();
             this.modelRepositoryHolder = request.getModelRepositoryHolder();
             this.repositoryMerging = request.getRepositoryMerging();
-            this.modelCache = request.getModelCache();
             this.listener = request.getListener();
             this.interimResult = request.getInterimResult();
             this.repositories = request.getRepositories();
@@ -286,11 +281,6 @@ public ModelBuilderRequestBuilder repositoryMerging(RepositoryMerging repository
             return this;
         }
 
-        public ModelBuilderRequestBuilder modelCache(ModelCache modelCache) {
-            this.modelCache = modelCache;
-            return this;
-        }
-
         public ModelBuilderRequestBuilder listener(Object listener) {
             this.listener = listener;
             return this;
@@ -321,7 +311,6 @@ public ModelBuilderRequest build() {
                     modelResolver,
                     modelRepositoryHolder,
                     repositoryMerging,
-                    modelCache,
                     listener,
                     interimResult,
                     repositories);
@@ -340,7 +329,6 @@ private static class DefaultModelBuilderRequest extends BaseRequest implements M
             private final ModelResolver modelResolver;
             private final Object modelRepositoryHolder;
             private final RepositoryMerging repositoryMerging;
-            private final ModelCache modelCache;
             private final Object listener;
             private final ModelBuilderResult interimResult;
             private final List<RemoteRepository> repositories;
@@ -360,7 +348,6 @@ private static class DefaultModelBuilderRequest extends BaseRequest implements M
                     ModelResolver modelResolver,
                     Object modelRepositoryHolder,
                     RepositoryMerging repositoryMerging,
-                    ModelCache modelCache,
                     Object listener,
                     ModelBuilderResult interimResult,
                     List<RemoteRepository> repositories) {
@@ -378,7 +365,6 @@ private static class DefaultModelBuilderRequest extends BaseRequest implements M
                 this.modelResolver = modelResolver;
                 this.modelRepositoryHolder = modelRepositoryHolder;
                 this.repositoryMerging = repositoryMerging;
-                this.modelCache = modelCache;
                 this.listener = listener;
                 this.interimResult = interimResult;
                 this.repositories = repositories != null ? List.copyOf(repositories) : null;
@@ -445,11 +431,6 @@ public RepositoryMerging getRepositoryMerging() {
                 return repositoryMerging;
             }
 
-            @Override
-            public ModelCache getModelCache() {
-                return modelCache;
-            }
-
             public Object getListener() {
                 return listener;
             }

…pache/maven/api/services/ModelCache.java …maven/api/services/model/ModelCache.javaapi/maven-api-core/src/main/java/org/apache/maven/api/services/ModelCache.java renamed to maven-api-impl/src/main/java/org/apache/maven/api/services/model/ModelCache.java api/maven-api-core/src/main/java/org/apache/maven/api/services/ModelCache.java renamed to 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
- * identity of a model. The tag allows for further classification of the associated data on the sole discretion of the
- * model builder.
+ * formed by a combination of group id, artifact id, version and tag, or by the pom path on the filesystem and tag.
+ * The tag allows for further classification of the associated data on the sole discretion of the 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();
+}