| /* |
| * Copyright 2009-2010 by The Regents of the University of California |
| * 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 from |
| * |
| * 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 edu.uci.ics.hyracks.control.nc.dataset; |
| |
| import java.nio.ByteBuffer; |
| import java.util.concurrent.Executor; |
| import java.util.logging.Level; |
| import java.util.logging.Logger; |
| |
| import edu.uci.ics.hyracks.api.comm.IFrameWriter; |
| import edu.uci.ics.hyracks.api.exceptions.HyracksDataException; |
| import edu.uci.ics.hyracks.comm.channels.NetworkOutputChannel; |
| |
| public class DatasetPartitionReader { |
| private static final Logger LOGGER = Logger.getLogger(DatasetPartitionReader.class.getName()); |
| |
| private final DatasetMemoryManager datasetMemoryManager; |
| |
| private final Executor executor; |
| |
| private final ResultState resultState; |
| |
| public DatasetPartitionReader(DatasetMemoryManager datasetMemoryManager, Executor executor, ResultState resultState) { |
| this.datasetMemoryManager = datasetMemoryManager; |
| this.executor = executor; |
| this.resultState = resultState; |
| } |
| |
| public void writeTo(final IFrameWriter writer) { |
| executor.execute(new Runnable() { |
| @Override |
| public void run() { |
| NetworkOutputChannel channel = (NetworkOutputChannel) writer; |
| channel.setFrameSize(resultState.getFrameSize()); |
| try { |
| resultState.readOpen(); |
| channel.open(); |
| try { |
| long offset = 0; |
| ByteBuffer buffer = ByteBuffer.allocate(resultState.getFrameSize()); |
| while (true) { |
| buffer.clear(); |
| long size = read(offset, buffer); |
| if (size <= 0) { |
| break; |
| } else if (size < buffer.limit()) { |
| throw new HyracksDataException("Premature end of file - readSize: " + size |
| + " buffer limit: " + buffer.limit()); |
| } |
| offset += size; |
| buffer.flip(); |
| channel.nextFrame(buffer); |
| } |
| } finally { |
| channel.close(); |
| resultState.readClose(); |
| } |
| } catch (HyracksDataException e) { |
| throw new RuntimeException(e); |
| } |
| if (LOGGER.isLoggable(Level.INFO)) { |
| LOGGER.info("result reading successful(" + resultState.getResultSetPartitionId() + ")"); |
| } |
| } |
| |
| private long read(long offset, ByteBuffer buffer) throws HyracksDataException { |
| if (datasetMemoryManager == null) { |
| return resultState.read(offset, buffer); |
| } else { |
| return resultState.read(datasetMemoryManager, offset, buffer); |
| } |
| } |
| }); |
| } |
| } |