org.mca.qmass.persistence.MongoDBTupleStore.java Source code

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Here is the source code for org.mca.qmass.persistence.MongoDBTupleStore.java

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/*
 * Copyright 2011 MCA
 *
 * 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 org.mca.qmass.persistence;

import com.mongodb.*;
import org.mca.qmass.core.serialization.JavaSerializationStrategy;
import org.mca.qmass.core.serialization.SerializationStrategy;
import org.mca.qmass.mongodb.MongoDBUtils;
import org.mca.yala.YALog;
import org.mca.yala.YALogFactory;

import java.util.List;

/**
 * User: malpay
 * Date: 17.10.2011
 * Time: 11:03
 */
public class MongoDBTupleStore implements TupleStore {

    private final static YALog log = YALogFactory.getLog(MongoDBTupleStore.class);

    private DB db;

    private SerializationStrategy ss = new JavaSerializationStrategy();

    public MongoDBTupleStore() {
        db = MongoDBUtils.instance().getDB("qmass");
    }

    @Override
    public Tuple get(Tuple tuple) {
        log.warn("get " + tuple);
        DBObject dbObj = new BasicDBObject();
        dbObj.put("key", tuple.getKey());
        DBObject found = db.getCollection(tuple.getType()).findOne(dbObj);
        log.trace("found " + found);
        if (found != null) {
            Object value = ss.deSerialize((byte[]) found.get("value"));
            log.trace("returning get " + value);
            return (Tuple) value;
        }
        return null;
    }

    @Override
    public void persist(Tuple tuple) {
        DBObject dbObj = new BasicDBObject();
        dbObj.put("key", tuple.getKey());
        dbObj.put("value", ss.serialize(tuple));
        remove(tuple);

        DBCollection dbColl = db.getCollection(tuple.getType());
        dbColl.save(dbObj);
        getKeysCollection(tuple.getType()).save(new BasicDBObject("key", tuple.getKey()));
        log.trace("persistet " + tuple);
    }

    @Override
    public void remove(Tuple tuple) {
        DBObject dbObj = new BasicDBObject();
        dbObj.put("key", tuple.getKey());
        db.getCollection(tuple.getType()).remove(dbObj);
        getKeysCollection(tuple.getType()).remove(new BasicDBObject("key", tuple.getKey()));
        log.trace("removed " + tuple);
    }

    @Override
    public List find(String type, FilterPredicate predicate) {
        final DBCollection collection = getKeysCollection(type);
        return new CursorList(new MongoDBColCursor(collection.find(), this, predicate, type));
    }

    private DBCollection getKeysCollection(String type) {
        return db.getCollection(getKeys(type));
    }

    private String getKeys(String type) {
        return "keys." + type;
    }
}