/*
* 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.spi.ConnectorPageSource;
import com.facebook.presto.spi.Page;
import com.facebook.presto.spi.type.Type;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.ListenableFuture;
import java.io.Closeable;
import java.io.IOException;
import java.util.List;
import static com.google.common.base.Preconditions.checkNotNull;
public class PageSourceOperator
implements Operator, Closeable
{
private final ConnectorPageSource pageSource;
private final List<Type> types;
private final OperatorContext operatorContext;
private long completedBytes;
private long readTimeNanos;
public PageSourceOperator(ConnectorPageSource pageSource, List<Type> types, OperatorContext operatorContext)
{
this.pageSource = checkNotNull(pageSource, "pageSource is null");
this.types = ImmutableList.copyOf(checkNotNull(types, "types is null"));
this.operatorContext = checkNotNull(operatorContext, "operatorContext is null");
}
@Override
public OperatorContext getOperatorContext()
{
return operatorContext;
}
@Override
public List<Type> getTypes()
{
return types;
}
@Override
public void finish()
{
try {
pageSource.close();
}
catch (IOException e) {
throw Throwables.propagate(e);
}
}
@Override
public boolean isFinished()
{
return pageSource.isFinished();
}
@Override
public ListenableFuture<?> isBlocked()
{
return NOT_BLOCKED;
}
@Override
public boolean needsInput()
{
return false;
}
@Override
public void addInput(Page page)
{
throw new UnsupportedOperationException();
}
@Override
public Page getOutput()
{
Page page = pageSource.getNextPage();
if (page == null) {
return null;
}
// update operator stats
long endCompletedBytes = pageSource.getCompletedBytes();
long endReadTimeNanos = pageSource.getReadTimeNanos();
operatorContext.recordGeneratedInput(endCompletedBytes - completedBytes, page.getPositionCount(), endReadTimeNanos - readTimeNanos);
completedBytes = endCompletedBytes;
readTimeNanos = endReadTimeNanos;
return page;
}
@Override
public void close()
throws IOException
{
pageSource.close();
}
}