/*
* Licensed 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 com.facebook.presto.operator;
import com.facebook.presto.memory.LocalMemoryContext;
import com.facebook.presto.metadata.Split;
import com.facebook.presto.spi.ColumnHandle;
import com.facebook.presto.spi.ConnectorPageSource;
import com.facebook.presto.spi.Page;
import com.facebook.presto.spi.UpdatablePageSource;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.split.EmptySplit;
import com.facebook.presto.split.EmptySplitPageSource;
import com.facebook.presto.split.PageSourceProvider;
import com.facebook.presto.sql.planner.plan.PlanNodeId;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.SettableFuture;
import java.io.Closeable;
import java.io.IOException;
import java.util.List;
import java.util.Optional;
import java.util.concurrent.CompletableFuture;
import java.util.function.Supplier;
import static com.google.common.base.Preconditions.checkState;
import static io.airlift.concurrent.MoreFutures.toListenableFuture;
import static java.util.Objects.requireNonNull;
public class TableScanOperator
implements SourceOperator, Closeable
{
public static class TableScanOperatorFactory
implements SourceOperatorFactory
{
private final int operatorId;
private final PlanNodeId sourceId;
private final PageSourceProvider pageSourceProvider;
private final List<Type> types;
private final List<ColumnHandle> columns;
private boolean closed;
public TableScanOperatorFactory(
int operatorId,
PlanNodeId sourceId,
PageSourceProvider pageSourceProvider,
List<Type> types,
Iterable<ColumnHandle> columns)
{
this.operatorId = operatorId;
this.sourceId = requireNonNull(sourceId, "sourceId is null");
this.types = requireNonNull(types, "types is null");
this.pageSourceProvider = requireNonNull(pageSourceProvider, "pageSourceProvider is null");
this.columns = ImmutableList.copyOf(requireNonNull(columns, "columns is null"));
}
@Override
public PlanNodeId getSourceId()
{
return sourceId;
}
@Override
public List<Type> getTypes()
{
return types;
}
@Override
public SourceOperator createOperator(DriverContext driverContext)
{
checkState(!closed, "Factory is already closed");
OperatorContext operatorContext = driverContext.addOperatorContext(operatorId, sourceId, TableScanOperator.class.getSimpleName());
return new TableScanOperator(
operatorContext,
sourceId,
pageSourceProvider,
types,
columns);
}
@Override
public void close()
{
closed = true;
}
}
private final OperatorContext operatorContext;
private final PlanNodeId planNodeId;
private final PageSourceProvider pageSourceProvider;
private final List<Type> types;
private final List<ColumnHandle> columns;
private final LocalMemoryContext systemMemoryContext;
private final SettableFuture<?> blocked = SettableFuture.create();
private Split split;
private ConnectorPageSource source;
private boolean finished;
private long completedBytes;
private long readTimeNanos;
public TableScanOperator(
OperatorContext operatorContext,
PlanNodeId planNodeId,
PageSourceProvider pageSourceProvider,
List<Type> types,
Iterable<ColumnHandle> columns)
{
this.operatorContext = requireNonNull(operatorContext, "operatorContext is null");
this.planNodeId = requireNonNull(planNodeId, "planNodeId is null");
this.types = requireNonNull(types, "types is null");
this.pageSourceProvider = requireNonNull(pageSourceProvider, "pageSourceProvider is null");
this.columns = ImmutableList.copyOf(requireNonNull(columns, "columns is null"));
this.systemMemoryContext = operatorContext.getSystemMemoryContext().newLocalMemoryContext();
}
@Override
public OperatorContext getOperatorContext()
{
return operatorContext;
}
@Override
public PlanNodeId getSourceId()
{
return planNodeId;
}
@Override
public Supplier<Optional<UpdatablePageSource>> addSplit(Split split)
{
requireNonNull(split, "split is null");
checkState(this.split == null, "Table scan split already set");
if (finished) {
return Optional::empty;
}
this.split = split;
Object splitInfo = split.getInfo();
if (splitInfo != null) {
operatorContext.setInfoSupplier(() -> new SplitOperatorInfo(splitInfo));
}
blocked.set(null);
if (split.getConnectorSplit() instanceof EmptySplit) {
source = new EmptySplitPageSource();
}
return () -> {
if (source instanceof UpdatablePageSource) {
return Optional.of((UpdatablePageSource) source);
}
return Optional.empty();
};
}
@Override
public void noMoreSplits()
{
if (split == null) {
finished = true;
}
blocked.set(null);
}
@Override
public List<Type> getTypes()
{
return types;
}
@Override
public void close()
{
finish();
}
@Override
public void finish()
{
finished = true;
blocked.set(null);
if (source != null) {
try {
source.close();
}
catch (IOException e) {
throw Throwables.propagate(e);
}
systemMemoryContext.setBytes(source.getSystemMemoryUsage());
}
}
@Override
public boolean isFinished()
{
if (!finished) {
finished = (source != null) && source.isFinished();
if (source != null) {
systemMemoryContext.setBytes(source.getSystemMemoryUsage());
}
}
return finished;
}
@Override
public ListenableFuture<?> isBlocked()
{
if (!blocked.isDone()) {
return blocked;
}
if (source != null) {
CompletableFuture<?> pageSourceBlocked = source.isBlocked();
return pageSourceBlocked.isDone() ? NOT_BLOCKED : toListenableFuture(pageSourceBlocked);
}
return NOT_BLOCKED;
}
@Override
public boolean needsInput()
{
return false;
}
@Override
public void addInput(Page page)
{
throw new UnsupportedOperationException(getClass().getName() + " can not take input");
}
@Override
public Page getOutput()
{
if (split == null) {
return null;
}
if (source == null) {
source = pageSourceProvider.createPageSource(operatorContext.getSession(), split, columns);
}
Page page = source.getNextPage();
if (page != null) {
// assure the page is in memory before handing to another operator
page.assureLoaded();
// update operator stats
long endCompletedBytes = source.getCompletedBytes();
long endReadTimeNanos = source.getReadTimeNanos();
operatorContext.recordGeneratedInput(endCompletedBytes - completedBytes, page.getPositionCount(), endReadTimeNanos - readTimeNanos);
completedBytes = endCompletedBytes;
readTimeNanos = endReadTimeNanos;
}
// updating system memory usage should happen after page is loaded.
systemMemoryContext.setBytes(source.getSystemMemoryUsage());
return page;
}
}