/*
* 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.flink.streaming.connectors.cassandra;
import com.datastax.driver.core.PreparedStatement;
import com.datastax.driver.core.ResultSet;
import com.google.common.util.concurrent.ListenableFuture;
import org.apache.flink.api.java.tuple.Tuple;
import org.apache.flink.configuration.Configuration;
/**
* Flink Sink to save data into a Cassandra cluster.
*
* @param <IN> Type of the elements emitted by this sink, it must extend {@link Tuple}
*/
public class CassandraTupleSink<IN extends Tuple> extends CassandraSinkBase<IN, ResultSet> {
private final String insertQuery;
private transient PreparedStatement ps;
public CassandraTupleSink(String insertQuery, ClusterBuilder builder) {
super(builder);
this.insertQuery = insertQuery;
}
@Override
public void open(Configuration configuration) {
super.open(configuration);
this.ps = session.prepare(insertQuery);
}
@Override
public ListenableFuture<ResultSet> send(IN value) {
Object[] fields = extract(value);
return session.executeAsync(ps.bind(fields));
}
private Object[] extract(IN record) {
Object[] al = new Object[record.getArity()];
for (int i = 0; i < record.getArity(); i++) {
al[i] = record.getField(i);
}
return al;
}
}