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package com.salesforce.phoenix.iterate;
import java.io.IOException;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.regionserver.MultiVersionConsistencyControl;
import org.apache.hadoop.hbase.regionserver.RegionScanner;
import com.salesforce.phoenix.schema.tuple.MultiKeyValueTuple;
import com.salesforce.phoenix.schema.tuple.Tuple;
import com.salesforce.phoenix.util.ServerUtil;
public class RegionScannerResultIterator extends BaseResultIterator {
private final RegionScanner scanner;
public RegionScannerResultIterator(RegionScanner scanner) {
this.scanner = scanner;
MultiVersionConsistencyControl.setThreadReadPoint(scanner.getMvccReadPoint());
}
@Override
public Tuple next() throws SQLException {
try {
// TODO: size
List<KeyValue> results = new ArrayList<KeyValue>();
// Results are potentially returned even when the return value of s.next is false
// since this is an indication of whether or not there are more values after the
// ones returned
boolean hasMore = scanner.nextRaw(results, null);
if (!hasMore && results.isEmpty()) {
return null;
}
// We instantiate a new tuple because in all cases currently we hang on to it (i.e.
// to compute and hold onto the TopN).
MultiKeyValueTuple tuple = new MultiKeyValueTuple();
tuple.setKeyValues(results);
return tuple;
} catch (IOException e) {
throw ServerUtil.parseServerException(e);
}
}
}