org.apache.drill.exec.store.mongo.config.MongoPStore.java Source code

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Here is the source code for org.apache.drill.exec.store.mongo.config.MongoPStore.java

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/**
 * 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.drill.exec.store.mongo.config;

import static org.apache.drill.exec.store.mongo.config.MongoPStoreProvider.pKey;

import java.io.IOException;
import java.util.Iterator;
import java.util.Map.Entry;
import java.util.NoSuchElementException;

import org.apache.drill.common.exceptions.DrillRuntimeException;
import org.apache.drill.exec.store.mongo.DrillMongoConstants;
import org.apache.drill.exec.store.sys.PStore;
import org.apache.drill.exec.store.sys.PStoreConfig;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.mongodb.BasicDBObject;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.WriteResult;

public class MongoPStore<V> implements PStore<V>, DrillMongoConstants {

    static final Logger logger = LoggerFactory.getLogger(MongoPStore.class);

    private final PStoreConfig<V> config;

    private final DBCollection collection;

    public MongoPStore(PStoreConfig<V> config, DBCollection collection) throws IOException {
        //    this.config = config;
        //    this.collection = collection;
        throw new UnsupportedOperationException("Mongo DB PStore not currently supported");
    }

    @Override
    public V get(String key) {
        try {
            DBObject get = new BasicDBObject().append(ID, key);
            DBCursor cursor = collection.find(get);
            if (cursor != null && cursor.hasNext()) {
                return value((byte[]) cursor.next().get(pKey));
            } else {
                return null;
            }
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            throw new DrillRuntimeException(e.getMessage(), e);
        }
    }

    @Override
    public void put(String key, V value) {
        try {
            DBObject putObj = new BasicDBObject(2);
            putObj.put(ID, key);
            putObj.put(pKey, bytes(value));
            collection.insert(putObj);
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            throw new DrillRuntimeException(e.getMessage(), e);
        }
    }

    @Override
    public boolean putIfAbsent(String key, V value) {
        try {
            DBObject check = new BasicDBObject(1).append(ID, key);
            DBObject putObj = new BasicDBObject(2);
            putObj.put(pKey, bytes(value));
            WriteResult wr = collection.update(check, putObj, true, false);
            return wr.getN() == 1 ? true : false;
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            throw new DrillRuntimeException(e.getMessage(), e);
        }
    }

    @Override
    public void delete(String key) {
        try {
            DBObject delete = new BasicDBObject(1).append(ID, key);
            collection.remove(delete);
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            throw new DrillRuntimeException(e.getMessage(), e);
        }
    }

    private byte[] bytes(V value) {
        try {
            return config.getSerializer().serialize(value);
        } catch (IOException e) {
            throw new DrillRuntimeException(e.getMessage(), e);
        }
    }

    private V value(byte[] serialize) {
        try {
            return config.getSerializer().deserialize(serialize);
        } catch (IOException e) {
            throw new DrillRuntimeException(e.getMessage(), e);
        }
    }

    @Override
    public Iterator<Entry<String, V>> iterator() {
        return new MongoIterator();
    }

    private class MongoIterator implements Iterator<Entry<String, V>> {

        private DBCursor cursor;

        public MongoIterator() {
            cursor = collection.find();
        }

        @Override
        public boolean hasNext() {
            return cursor.hasNext();
        }

        @Override
        public Entry<String, V> next() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }
            return new DeferredEntry(cursor.next());
        }

        @Override
        public void remove() {
            cursor.remove();
        }
    }

    private class DeferredEntry implements Entry<String, V> {

        private DBObject result;

        public DeferredEntry(DBObject result) {
            this.result = result;
        }

        @Override
        public String getKey() {
            return result.get(ID).toString();
        }

        @Override
        public V getValue() {
            return get(result.get(ID).toString());
        }

        @Override
        public V setValue(V value) {
            throw new UnsupportedOperationException();
        }
    }

    @Override
    public void close() {
    }
}