org.apache.spark.sql.vectorized.ColumnarBatch Maven / Gradle / Ivy
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* 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.spark.sql.vectorized;
import java.util.*;
import org.apache.spark.annotation.InterfaceStability;
import org.apache.spark.sql.catalyst.InternalRow;
import org.apache.spark.sql.execution.vectorized.MutableColumnarRow;
/**
* This class wraps multiple ColumnVectors as a row-wise table. It provides a row view of this
* batch so that Spark can access the data row by row. Instance of it is meant to be reused during
* the entire data loading process.
*/
@InterfaceStability.Evolving
public final class ColumnarBatch {
private int numRows;
private final ColumnVector[] columns;
// Staging row returned from `getRow`.
private final MutableColumnarRow row;
/**
* Called to close all the columns in this batch. It is not valid to access the data after
* calling this. This must be called at the end to clean up memory allocations.
*/
public void close() {
for (ColumnVector c: columns) {
c.close();
}
}
/**
* Returns an iterator over the rows in this batch.
*/
public Iterator rowIterator() {
final int maxRows = numRows;
final MutableColumnarRow row = new MutableColumnarRow(columns);
return new Iterator() {
int rowId = 0;
@Override
public boolean hasNext() {
return rowId < maxRows;
}
@Override
public InternalRow next() {
if (rowId >= maxRows) {
throw new NoSuchElementException();
}
row.rowId = rowId++;
return row;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
};
}
/**
* Sets the number of rows in this batch.
*/
public void setNumRows(int numRows) {
this.numRows = numRows;
}
/**
* Returns the number of columns that make up this batch.
*/
public int numCols() { return columns.length; }
/**
* Returns the number of rows for read, including filtered rows.
*/
public int numRows() { return numRows; }
/**
* Returns the column at `ordinal`.
*/
public ColumnVector column(int ordinal) { return columns[ordinal]; }
/**
* Returns the row in this batch at `rowId`. Returned row is reused across calls.
*/
public InternalRow getRow(int rowId) {
assert(rowId >= 0 && rowId < numRows);
row.rowId = rowId;
return row;
}
public ColumnarBatch(ColumnVector[] columns) {
this.columns = columns;
this.row = new MutableColumnarRow(columns);
}
}