/*
* 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.ignite.internal.processors.query.h2.twostep;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.ignite.cluster.ClusterNode;
import org.apache.ignite.internal.GridKernalContext;
import org.apache.ignite.internal.processors.query.h2.opt.GridH2Cursor;
import org.apache.ignite.internal.processors.query.h2.opt.GridH2RowFactory;
import org.h2.engine.Session;
import org.h2.index.Cursor;
import org.h2.index.IndexType;
import org.h2.result.Row;
import org.h2.result.SearchRow;
import org.h2.result.SortOrder;
import org.h2.table.Column;
import org.h2.table.IndexColumn;
import org.h2.table.TableFilter;
import org.h2.value.Value;
/**
* Unsorted merge index.
*/
public final class GridMergeIndexUnsorted extends GridMergeIndex {
/** */
private static final IndexType TYPE = IndexType.createScan(false);
/** */
private final PollableQueue<GridResultPage> queue = new PollableQueue<>();
/** */
private final AtomicInteger activeSources = new AtomicInteger(-1);
/** */
private Iterator<Value[]> iter = Collections.emptyIterator();
/**
* @param ctx Context.
* @param tbl Table.
* @param name Index name.
*/
public GridMergeIndexUnsorted(GridKernalContext ctx, GridMergeTable tbl, String name) {
super(ctx, tbl, name, TYPE, IndexColumn.wrap(tbl.getColumns()));
}
/**
* @param ctx Context.
* @return Dummy index instance.
*/
public static GridMergeIndexUnsorted createDummy(GridKernalContext ctx) {
return new GridMergeIndexUnsorted(ctx);
}
/**
* @param ctx Context.
*/
private GridMergeIndexUnsorted(GridKernalContext ctx) {
super(ctx);
}
/** {@inheritDoc} */
@Override public void setSources(Collection<ClusterNode> nodes, int segmentsCnt) {
super.setSources(nodes, segmentsCnt);
int x = nodes.size() * segmentsCnt;
assert x > 0: x;
activeSources.set(x);
}
/** {@inheritDoc} */
@Override public boolean fetchedAll() {
int x = activeSources.get();
assert x >= 0: x; // This method must not be called if the sources were not set.
return x == 0 && queue.isEmpty();
}
/** {@inheritDoc} */
@Override protected void addPage0(GridResultPage page) {
assert page.rowsInPage() > 0 || page.isLast() || page.isFail();
// Do not add empty page to avoid premature stream termination.
if (page.rowsInPage() != 0 || page.isFail())
queue.add(page);
if (page.isLast()) {
int x = activeSources.decrementAndGet();
assert x >= 0: x;
if (x == 0) // Always terminate with empty iterator.
queue.add(createDummyLastPage(page));
}
}
/** {@inheritDoc} */
@Override public double getCost(Session ses, int[] masks, TableFilter[] filters, int filter, SortOrder sortOrder, HashSet<Column> allColumnsSet) {
return getCostRangeIndex(masks, getRowCountApproximation(), filters, filter, sortOrder, true, allColumnsSet);
}
/** {@inheritDoc} */
@Override protected Cursor findAllFetched(List<Row> fetched, SearchRow first, SearchRow last) {
// This index is unsorted: have to ignore bounds.
return new GridH2Cursor(fetched.iterator());
}
/** {@inheritDoc} */
@Override protected Cursor findInStream(SearchRow first, SearchRow last) {
// This index is unsorted: have to ignore bounds.
return new FetchingCursor(null, null, new Iterator<Row>() {
@Override public boolean hasNext() {
iter = pollNextIterator(queue, iter);
return iter.hasNext();
}
@Override public Row next() {
return GridH2RowFactory.create(iter.next());
}
@Override public void remove() {
throw new UnsupportedOperationException();
}
});
}
/**
*/
private static class PollableQueue<X> extends LinkedBlockingQueue<X> implements Pollable<X> {
// No-op.
}
}