content: /*
   *  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.causeway.core.metamodel.facets.collections.javautilcollection;
  
  import java.util.Collection;
  import java.util.function.Supplier;
  import java.util.stream.Stream;
  
  import org.jspecify.annotations.Nullable;
  
  import org.apache.causeway.commons.internal.base._Casts;
  import org.apache.causeway.commons.internal.base._NullSafe;
  import org.apache.causeway.core.metamodel.facetapi.FacetHolder;
  import org.apache.causeway.core.metamodel.facets.collections.CollectionFacetAbstract;
  import org.apache.causeway.core.metamodel.object.ManagedObject;
  import org.apache.causeway.core.metamodel.spec.ObjectSpecification;
  
  public class JavaCollectionFacet extends CollectionFacetAbstract {
  
      public JavaCollectionFacet(final FacetHolder holder) {
          super(holder);
      }
  
      @Override
      public Object populatePojo(
              final Supplier<Object> emptyCollectionPojoFactory,
              final ObjectSpecification collectionSpec,
              final Stream<ManagedObject> initData,
              final int elementCount) {
  
          final Collection<? super Object> pojoCollection = _Casts.uncheckedCast(emptyCollectionPojoFactory.get());
          pojoCollection.clear(); // just in case
          initData.forEach(pojoCollection::add);
          return pojoCollection;
      }
  
      /**
       * @param collectionAdapter - {@link ManagedObject} wrapping a collection.
       */
      @Override
      public Stream<ManagedObject> stream(final @Nullable ManagedObject collectionAdapter) {
          return _NullSafe.stream(pojoCollection(collectionAdapter))
                  .map(super.getObjectManager()::adapt);
      }
  
      /**
       * @param collectionAdapter - {@link ManagedObject} wrapping a collection.
       */
      @Override
      public int size(final @Nullable ManagedObject collectionAdapter) {
          return _NullSafe.size(pojoCollection(collectionAdapter));
      }
  
      /**
       * The underlying collection of objects (not {@link ManagedObject}s).
       */
      @Nullable
      private Collection<?> pojoCollection(final @Nullable ManagedObject collectionAdapter) {
          return collectionAdapter == null
                  ? (Collection<?>) null
                  : (Collection<?>) collectionAdapter.getPojo();
      }
  
  }
  