org.springframework.cloud.gcp.data.datastore.repository.query.AbstractDatastoreQuery Maven / Gradle / Ivy

/*
 * Copyright 2017-2019 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.cloud.gcp.data.datastore.repository.query;

import java.lang.reflect.Array;
import java.util.List;
import java.util.stream.Collectors;

import org.springframework.cloud.gcp.data.datastore.core.DatastoreOperations;
import org.springframework.cloud.gcp.data.datastore.core.mapping.DatastoreMappingContext;
import org.springframework.data.repository.query.QueryMethod;
import org.springframework.data.repository.query.RepositoryQuery;

/**
 * Abstract class for implementing Cloud Datastore query methods.
 *
 * @param  the domain type of the repository class containing this query method.
 *
 * @author Chengyuan Zhao
 *
 * @since 1.1
 */
public abstract class AbstractDatastoreQuery implements RepositoryQuery {

	final DatastoreMappingContext datastoreMappingContext;

	final DatastoreQueryMethod queryMethod;

	final DatastoreOperations datastoreOperations;

	final Class entityType;

	public AbstractDatastoreQuery(DatastoreQueryMethod queryMethod,
							DatastoreOperations datastoreOperations,
			DatastoreMappingContext datastoreMappingContext, Class entityType) {
		this.queryMethod = queryMethod;
		this.datastoreOperations = datastoreOperations;
		this.datastoreMappingContext = datastoreMappingContext;
		this.entityType = entityType;
	}

	@Override
	public QueryMethod getQueryMethod() {
		return this.queryMethod;
	}

	/**
	 * Convert collection-like param from the query method into an array of compatible types
	 * for Datastore.
	 * @param param the raw param
	 * @return an array of a compatible type.
	 */
	protected Object[] convertCollectionParamToCompatibleArray(List param) {
		List converted = param.stream()
				.map((x) -> this.datastoreOperations.getDatastoreEntityConverter().getConversions().convertOnWriteSingle(x)
						.get())
				.collect(Collectors.toList());
		return converted.toArray(
				(Object[]) Array.newInstance(converted.isEmpty()
						? String.class // if there are no items in the param
						: converted.get(0).getClass(), converted.size()));
	}

	Object processRawObjectForProjection(Object object) {
		return this.queryMethod.getResultProcessor().processResult(object);
	}

	public DatastoreOperations getDatastoreOperations() {
		return this.datastoreOperations;
	}

	boolean isPageQuery() {
		return getQueryMethod().isPageQuery();
	}

	boolean isSliceQuery() {
		return getQueryMethod().isSliceQuery();
	}

}