/**
* 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.TColumn;
import org.apache.hive.service.cli.thrift.TRow;
import org.apache.hive.service.cli.thrift.TRowSet;
/**
* ColumnBasedSet.
*/
public class ColumnBasedSet implements RowSet {
private long startOffset;
private final Type[] types; // non-null only for writing (server-side)
private final List<Column> columns;
public ColumnBasedSet(TableSchema schema) {
types = schema.toTypes();
columns = new ArrayList<Column>();
for (ColumnDescriptor colDesc : schema.getColumnDescriptors()) {
columns.add(new Column(colDesc.getType()));
}
}
public ColumnBasedSet(TRowSet tRowSet) {
types = null;
columns = new ArrayList<Column>();
for (TColumn tvalue : tRowSet.getColumns()) {
columns.add(new Column(tvalue));
}
startOffset = tRowSet.getStartRowOffset();
}
private ColumnBasedSet(Type[] types, List<Column> columns, long startOffset) {
this.types = types;
this.columns = columns;
this.startOffset = startOffset;
}
@Override
public ColumnBasedSet addRow(Object[] fields) {
for (int i = 0; i < fields.length; i++) {
columns.get(i).addValue(types[i], fields[i]);
}
return this;
}
public List<Column> getColumns() {
return columns;
}
@Override
public int numColumns() {
return columns.size();
}
@Override
public int numRows() {
return columns.isEmpty() ? 0 : columns.get(0).size();
}
@Override
public ColumnBasedSet extractSubset(int maxRows) {
int numRows = Math.min(numRows(), maxRows);
List<Column> subset = new ArrayList<Column>();
for (int i = 0; i < columns.size(); i++) {
subset.add(columns.get(i).extractSubset(0, numRows));
}
ColumnBasedSet result = new ColumnBasedSet(types, subset, startOffset);
startOffset += numRows;
return result;
}
@Override
public long getStartOffset() {
return startOffset;
}
@Override
public void setStartOffset(long startOffset) {
this.startOffset = startOffset;
}
public TRowSet toTRowSet() {
TRowSet tRowSet = new TRowSet(startOffset, new ArrayList<TRow>());
for (int i = 0; i < columns.size(); i++) {
tRowSet.addToColumns(columns.get(i).toTColumn());
}
return tRowSet;
}
@Override
public Iterator<Object[]> iterator() {
return new Iterator<Object[]>() {
private int index;
private final Object[] convey = new Object[numColumns()];
@Override
public boolean hasNext() {
return index < numRows();
}
@Override
public Object[] next() {
for (int i = 0; i < columns.size(); i++) {
convey[i] = columns.get(i).get(index);
}
index++;
return convey;
}
@Override
public void remove() {
throw new UnsupportedOperationException("remove");
}
};
}
public Object[] fill(int index, Object[] convey) {
for (int i = 0; i < columns.size(); i++) {
convey[i] = columns.get(i).get(index);
}
return convey;
}
}