org.springframework.data.neo4j.mapping.Neo4jPersistentEntity.java Source code

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Here is the source code for org.springframework.data.neo4j.mapping.Neo4jPersistentEntity.java

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/*
 * Copyright 2011-2019 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.
 * You may obtain a copy of the License at
 *
 *      https://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.springframework.data.neo4j.mapping;

import org.springframework.data.mapping.MappingException;
import org.springframework.data.mapping.PersistentProperty;
import org.springframework.data.mapping.model.BasicPersistentEntity;
import org.springframework.data.neo4j.mapping.Neo4jPersistentProperty.PropertyType;
import org.springframework.data.support.IsNewStrategy;
import org.springframework.data.util.TypeInformation;

/**
 * This class implements Spring Data's PersistentEntity interface, scavenging the required data from the OGM's mapping
 * classes in order to for SDN to play nicely with Spring Data REST. The main thing to note is that this class is
 * effectively a shim for ClassInfo. We don't reload all the mapping information again.
 * <p>
 * These attributes do not appear to be used/needed for SDN 4 to inter-operate correctly with SD-REST:
 * </p>
 * <ul>
 * <li>typeAlias</li>
 * <li>typeInformation</li>
 * <li>preferredConstructor (we always use the default constructor)</li>
 * <li>versionProperty</li>
 * </ul>
 * Consequently their associated getter methods always return default values of null or [true|false] However, because
 * these method calls are not expected, we also log a warning message if they get invoked
 *
 * @author Vince Bickers
 * @author Adam George
 * @author Mark Paluch
 * @author Oliver Gierke
 * @author Michael J. Simons
 * @since 4.0.0
 */
public class Neo4jPersistentEntity<T> extends BasicPersistentEntity<T, Neo4jPersistentProperty> {

    /**
     * Constructs a new {@link Neo4jPersistentEntity} based on the given type information.
     *
     * @param information The {@link TypeInformation} upon which to base this persistent entity.
     */
    Neo4jPersistentEntity(TypeInformation<T> information) {
        super(information);
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.data.mapping.model.BasicPersistentEntity#getFallbackIsNewStrategy()
     */
    @Override
    protected IsNewStrategy getFallbackIsNewStrategy() {
        return new Neo4jIsNewStrategy(this);
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.data.mapping.model.BasicPersistentEntity#returnPropertyIfBetterIdPropertyCandidateOrNull(PersistentProperty)
     */
    @Override
    protected Neo4jPersistentProperty returnPropertyIfBetterIdPropertyCandidateOrNull(
            Neo4jPersistentProperty property) {

        if (!property.isIdProperty()) {
            return null;
        }

        Neo4jPersistentProperty existingIdProperty = this.getIdProperty();
        Neo4jPersistentProperty preferredIdProperty = existingIdProperty;

        if (existingIdProperty == null) {
            preferredIdProperty = property;
        } else if (existingIdProperty.getPropertyType() == property.getPropertyType()) {
            throw new MappingException(String.format(
                    "Attempt to add id property %s but already have property %s registered "
                            + "as id. Check your mapping configuration!",
                    property.getField(), existingIdProperty.getField()));
        } else if (existingIdProperty.getPropertyType() == PropertyType.INTERNAL_ID_PROPERTY
                && property.getPropertyType() == PropertyType.ID_PROPERTY) {
            preferredIdProperty = property;
        }
        return preferredIdProperty;
    }

    /**
     * Custom {@link IsNewStrategy} to also consider entities with identifiers of negative Long values new.
     * See also DATAGRAPH-1031.
     *
     * @author Frantisek Hartman
     * @author Oliver Gierke
     */
    private static class Neo4jIsNewStrategy implements IsNewStrategy {

        private final Neo4jPersistentEntity<?> entity;

        private Neo4jIsNewStrategy(Neo4jPersistentEntity<?> entity) {
            this.entity = entity;
        }

        /*
         * (non-Javadoc)
         * @see org.springframework.data.support.IsNewStrategy#isNew(java.lang.Object)
         */
        @Override
        public boolean isNew(Object bean) {

            PersistentProperty<? extends PersistentProperty<?>> property = entity.getRequiredIdProperty();
            Object value = entity.getPropertyAccessor(bean).getProperty(property);

            return value == null || (value instanceof Long && ((Long) value) < 0);
        }
    }
}