org.apache.flink.streaming.connectors.cassandra.AbstractCassandraTupleSink Maven / Gradle / Ivy
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* 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,
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* See the License for the specific language governing permissions and
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package org.apache.flink.streaming.connectors.cassandra;
import org.apache.flink.configuration.Configuration;
import com.datastax.driver.core.BoundStatement;
import com.datastax.driver.core.PreparedStatement;
import com.datastax.driver.core.ResultSet;
import com.google.common.util.concurrent.ListenableFuture;
/**
* Abstract sink to write tuple-like values into a Cassandra cluster.
*
* @param Type of the elements emitted by this sink
*/
public abstract class AbstractCassandraTupleSink extends CassandraSinkBase {
private final String insertQuery;
private transient PreparedStatement ps;
private final boolean ignoreNullFields;
public AbstractCassandraTupleSink(
String insertQuery,
ClusterBuilder builder,
CassandraSinkBaseConfig config,
CassandraFailureHandler failureHandler) {
super(builder, config, failureHandler);
this.insertQuery = insertQuery;
this.ignoreNullFields = config.getIgnoreNullFields();
}
@Override
public void open(Configuration configuration) {
super.open(configuration);
this.ps = session.prepare(insertQuery);
}
@Override
public ListenableFuture send(IN value) {
Object[] fields = extract(value);
return session.executeAsync(bind(fields));
}
private BoundStatement bind(Object[] fields) {
BoundStatement bs = ps.bind(fields);
if (ignoreNullFields) {
for (int i = 0; i < fields.length; i++) {
if (fields[i] == null) {
bs.unset(i);
}
}
}
return bs;
}
protected abstract Object[] extract(IN record);
}