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/*
* Copyright 2021-2022 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.
* 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.cassandra.core.mapping;
import java.util.function.Predicate;
import org.springframework.data.util.Predicates;
import org.springframework.lang.Nullable;
/**
* Utility to translate a {@link CassandraPersistentProperty} into a corresponding property from a different
* {@link CassandraPersistentEntity} by looking it up by name.
*
* Mainly used within the framework.
*
* @author Mark Paluch
* @since 3.4
*/
public class PersistentPropertyTranslator {
/**
* Translate a {@link CassandraPersistentProperty} into a corresponding property from a different
* {@link CassandraPersistentEntity}.
*
* @param property must not be {@literal null}.
* @return the translated property. Can be the original {@code property}.
*/
public CassandraPersistentProperty translate(CassandraPersistentProperty property) {
return property;
}
/**
* Create a new {@link PersistentPropertyTranslator}.
*
* @param targetEntity must not be {@literal null}.
* @return the property translator to use.
*/
public static PersistentPropertyTranslator create(@Nullable CassandraPersistentEntity targetEntity) {
return create(targetEntity, Predicates.isTrue());
}
/**
* Create a new {@link PersistentPropertyTranslator} accepting a {@link Predicate filter predicate} whether the
* translation should happen at all.
*
* @param targetEntity must not be {@literal null}.
* @param translationFilter must not be {@literal null}.
* @return the property translator to use.
*/
public static PersistentPropertyTranslator create(@Nullable CassandraPersistentEntity targetEntity,
Predicate translationFilter) {
return targetEntity != null ? new EntityPropertyTranslator(targetEntity, translationFilter)
: new PersistentPropertyTranslator();
}
private static class EntityPropertyTranslator extends PersistentPropertyTranslator {
private final CassandraPersistentEntity targetEntity;
private final Predicate translationFilter;
EntityPropertyTranslator(CassandraPersistentEntity targetEntity,
Predicate translationFilter) {
this.targetEntity = targetEntity;
this.translationFilter = translationFilter;
}
@Override
public CassandraPersistentProperty translate(CassandraPersistentProperty property) {
if (!translationFilter.test(property)) {
return property;
}
CassandraPersistentProperty targetProperty = targetEntity.getPersistentProperty(property.getName());
return targetProperty != null ? targetProperty : property;
}
}
}