/**
* 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.tajo.engine.planner.physical;
import org.apache.tajo.worker.TaskAttemptContext;
import org.apache.tajo.engine.planner.logical.SortNode;
import org.apache.tajo.storage.Tuple;
import org.apache.tajo.storage.VTuple;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
public class MemSortExec extends SortExec {
private final SortNode plan;
private List<Tuple> tupleSlots;
private boolean sorted = false;
private Iterator<Tuple> iterator;
public MemSortExec(final TaskAttemptContext context,
SortNode plan, PhysicalExec child) {
super(context, plan.getInSchema(), plan.getOutSchema(), child, plan.getSortKeys());
this.plan = plan;
}
public void init() throws IOException {
super.init();
this.tupleSlots = new ArrayList<Tuple>(1000);
}
@Override
public Tuple next() throws IOException {
if (!sorted) {
Tuple tuple;
while ((tuple = child.next()) != null) {
tupleSlots.add(new VTuple(tuple));
}
Collections.sort(tupleSlots, getComparator());
this.iterator = tupleSlots.iterator();
sorted = true;
}
if (iterator.hasNext()) {
return this.iterator.next();
} else {
return null;
}
}
@Override
public void rescan() throws IOException {
super.rescan();
this.iterator = tupleSlots.iterator();
sorted = true;
}
public SortNode getPlan() {
return this.plan;
}
}