hyracks/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorNodePushable.java

/*
 * 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.storage.am.common.dataflow;

import java.util.logging.Level;
import java.util.logging.Logger;

import edu.uci.ics.hyracks.api.comm.IFrameWriter;
import edu.uci.ics.hyracks.api.context.IHyracksTaskContext;
import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
import edu.uci.ics.hyracks.api.io.FileReference;
import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorNodePushable;
import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;

public class TreeIndexDropOperatorNodePushable extends AbstractOperatorNodePushable {
    private static final Logger LOGGER = Logger.getLogger(TreeIndexDropOperatorNodePushable.class.getName());

    private final IHyracksTaskContext ctx;
    private IIndexRegistryProvider<IIndex> treeIndexRegistryProvider;
    private IStorageManagerInterface storageManager;
    private IFileSplitProvider fileSplitProvider;
    private int partition;

    public TreeIndexDropOperatorNodePushable(IHyracksTaskContext ctx, IStorageManagerInterface storageManager,
            IIndexRegistryProvider<IIndex> treeIndexRegistryProvider, IFileSplitProvider fileSplitProvider,
            int partition) {
        this.ctx = ctx;
        this.storageManager = storageManager;
        this.treeIndexRegistryProvider = treeIndexRegistryProvider;
        this.fileSplitProvider = fileSplitProvider;
        this.partition = partition;
    }

    @Override
    public void deinitialize() throws HyracksDataException {
    }

    @Override
    public int getInputArity() {
        return 0;
    }

    @Override
    public IFrameWriter getInputFrameWriter(int index) {
        return null;
    }

    @Override
    public void initialize() throws HyracksDataException {
        try {
            IndexRegistry<IIndex> treeIndexRegistry = treeIndexRegistryProvider.getRegistry(ctx);
            IBufferCache bufferCache = storageManager.getBufferCache(ctx);
            IFileMapProvider fileMapProvider = storageManager.getFileMapProvider(ctx);

            FileReference f = fileSplitProvider.getFileSplits()[partition].getLocalFile();
            int indexFileId = -1;
            synchronized (fileMapProvider) {
                boolean fileIsMapped = fileMapProvider.isMapped(f);
                if (!fileIsMapped) {
                    throw new HyracksDataException("Cannot drop Tree with name " + f.toString()
                            + ". No file mapping exists.");
                }
                indexFileId = fileMapProvider.lookupFileId(f);
            }
            // Unregister tree instance.
            synchronized (treeIndexRegistry) {
                treeIndexRegistry.unregister(indexFileId);
            }

            // remove name to id mapping
            bufferCache.deleteFile(indexFileId, false);
        }
        // TODO: for the time being we don't throw,
        // with proper exception handling (no hanging job problem) we should
        // throw
        catch (Exception e) {
            if (LOGGER.isLoggable(Level.WARNING)) {
                LOGGER.warning("Tree Drop Operator Failed Due To Exception: " + e.getMessage());
            }
        }
    }

    @Override
    public void setOutputFrameWriter(int index, IFrameWriter writer, RecordDescriptor recordDesc) {
    }
}