/**
* Copyright 2011 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
*
* 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.springframework.data.neo4j.support.query;
import org.neo4j.cypher.commands.Query;
import org.neo4j.cypher.javacompat.CypherParser;
import org.neo4j.cypher.javacompat.ExecutionEngine;
import org.neo4j.cypher.javacompat.ExecutionResult;
import org.neo4j.graphdb.GraphDatabaseService;
import org.springframework.dao.InvalidDataAccessResourceUsageException;
import org.springframework.data.neo4j.conversion.DefaultConverter;
import org.springframework.data.neo4j.conversion.QueryResult;
import org.springframework.data.neo4j.conversion.QueryResultBuilder;
import org.springframework.data.neo4j.conversion.ResultConverter;
import java.util.Map;
public class CypherQueryEngine implements QueryEngine<Map<String,Object>> {
final ExecutionEngine executionEngine;
private ResultConverter resultConverter;
public CypherQueryEngine(GraphDatabaseService graphDatabaseService) {
this(graphDatabaseService, new DefaultConverter());
}
public CypherQueryEngine(GraphDatabaseService graphDatabaseService, ResultConverter resultConverter) {
this.resultConverter = resultConverter != null ? resultConverter : new DefaultConverter();
this.executionEngine = new ExecutionEngine(graphDatabaseService);
}
@Override
public QueryResult<Map<String, Object>> query(String statement, Map<String, Object> params) {
try {
String parametrizedQuery = QueryResultBuilder.replaceParams(statement,params);
ExecutionResult result = parseAndExecuteQuery(parametrizedQuery);
return new QueryResultBuilder<Map<String,Object>>(result,resultConverter);
} catch (Exception e) {
throw new InvalidDataAccessResourceUsageException("Error executing statement " + statement, e);
}
}
private ExecutionResult parseAndExecuteQuery(String statement) {
try {
CypherParser parser = new CypherParser();
Query query = parser.parse(statement);
return executionEngine.execute(query);
} catch(Exception e) {
throw new InvalidDataAccessResourceUsageException("Error executing statement " + statement, e);
}
}
}