/*
* 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.solr.hadoop.dedup;
import java.util.Collections;
import java.util.Iterator;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer.Context;
import org.apache.solr.common.SolrInputDocument;
/**
* UpdateConflictResolver implementation that rejects multiple documents with
* the same key with an exception.
*/
public final class RejectingUpdateConflictResolver implements UpdateConflictResolver {
@Override
public Iterator<SolrInputDocument> orderUpdates(Text key, Iterator<SolrInputDocument> updates, Context ctx) {
SolrInputDocument firstUpdate = null;
while (updates.hasNext()) {
if (firstUpdate == null) {
firstUpdate = updates.next();
assert firstUpdate != null;
} else {
throw new IllegalArgumentException("Update conflict! Documents with the same unique key are forbidden: "
+ key);
}
}
assert firstUpdate != null;
return Collections.singletonList(firstUpdate).iterator();
}
}