/**
* 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.hive.service.cli;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.hive.service.cli.thrift.TColumnValue;
import org.apache.hive.service.cli.thrift.TRow;
import org.apache.hive.service.cli.thrift.TRowSet;
/**
* RowBasedSet
*/
public class RowBasedSet implements RowSet {
private long startOffset;
private final Type[] types; // non-null only for writing (server-side)
private final RemovableList<TRow> rows;
public RowBasedSet(TableSchema schema) {
types = schema.toTypes();
rows = new RemovableList<TRow>();
}
public RowBasedSet(TRowSet tRowSet) {
types = null;
rows = new RemovableList<TRow>(tRowSet.getRows());
startOffset = tRowSet.getStartRowOffset();
}
private RowBasedSet(Type[] types, List<TRow> rows, long startOffset) {
this.types = types;
this.rows = new RemovableList<TRow>(rows);
this.startOffset = startOffset;
}
@Override
public RowBasedSet addRow(Object[] fields) {
TRow tRow = new TRow();
for (int i = 0; i < fields.length; i++) {
tRow.addToColVals(ColumnValue.toTColumnValue(types[i], fields[i]));
}
rows.add(tRow);
return this;
}
@Override
public int numColumns() {
return rows.isEmpty() ? 0 : rows.get(0).getColVals().size();
}
@Override
public int numRows() {
return rows.size();
}
public RowBasedSet extractSubset(int maxRows) {
int numRows = Math.min(numRows(), maxRows);
RowBasedSet result = new RowBasedSet(types, rows.subList(0, numRows), startOffset);
rows.removeRange(0, numRows);
startOffset += numRows;
return result;
}
public long getStartOffset() {
return startOffset;
}
public void setStartOffset(long startOffset) {
this.startOffset = startOffset;
}
public int getSize() {
return rows.size();
}
public TRowSet toTRowSet() {
TRowSet tRowSet = new TRowSet();
tRowSet.setStartRowOffset(startOffset);
tRowSet.setRows(new ArrayList<TRow>(rows));
return tRowSet;
}
@Override
public Iterator<Object[]> iterator() {
return new Iterator<Object[]>() {
final Iterator<TRow> iterator = rows.iterator();
final Object[] convey = new Object[numColumns()];
@Override
public boolean hasNext() {
return iterator.hasNext();
}
@Override
public Object[] next() {
TRow row = iterator.next();
List<TColumnValue> values = row.getColVals();
for (int i = 0; i < values.size(); i++) {
convey[i] = ColumnValue.toColumnValue(values.get(i));
}
return convey;
}
@Override
public void remove() {
throw new UnsupportedOperationException("remove");
}
};
}
private static class RemovableList<E> extends ArrayList<E> {
public RemovableList() { super(); }
public RemovableList(List<E> rows) { super(rows); }
@Override
public void removeRange(int fromIndex, int toIndex) {
super.removeRange(fromIndex, toIndex);
}
}
}