org.alfresco.bm.file.FileDataServiceImpl.java Source code

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/*
 * Copyright (C) 2005-2014 Alfresco Software Limited.
 *
 * This file is part of Alfresco
 *
 * Alfresco is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Alfresco is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
 */
package org.alfresco.bm.file;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.InitializingBean;

import com.mongodb.BasicDBObjectBuilder;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.WriteConcern;
import com.mongodb.WriteResult;

/**
 * Concrete service implementation of {@link FileDataService} based on MongoDB.
 *
 * @author Derek Hulley
 * @since 1.4
 */
public class FileDataServiceImpl implements FileDataService, InitializingBean {
    public static final String FIELD_FILESET = "fileset";
    public static final String FIELD_REMOTE_NAME = "remoteName";
    public static final String FIELD_LOCAL_NAME = "localName";
    public static final String FIELD_EXTENSION = "extension";
    public static final String FIELD_ENCODING = "encoding";
    public static final String FIELD_LOCALE = "locale";
    public static final String FIELD_SIZE = "size";
    public static final String FIELD_RANDOMIZER = "randomizer";

    private static final Log logger = LogFactory.getLog(FileDataServiceImpl.class);

    private DBCollection collection;

    public FileDataServiceImpl(DB db, String collection) {
        this.collection = db.getCollection(collection);
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        checkIndexes();
    }

    /**
     * Ensure that the MongoDB collection has the required indexes associated with
     * this user bean.
     */
    private void checkIndexes() {
        collection.setWriteConcern(WriteConcern.SAFE);

        DBObject idxRandomizer = BasicDBObjectBuilder.start(FIELD_FILESET, 1).add(FIELD_RANDOMIZER, 1).get();
        DBObject optRandomizer = BasicDBObjectBuilder.start("name", "idx_randomizer").add("unique", Boolean.FALSE)
                .get();
        collection.createIndex(idxRandomizer, optRandomizer);

        DBObject idxExtension = BasicDBObjectBuilder.start(FIELD_FILESET, 1).add(FIELD_EXTENSION, 1)
                .add(FIELD_RANDOMIZER, 1).get();
        DBObject optExtension = BasicDBObjectBuilder.start("name", "idx_extension").add("unique", Boolean.FALSE)
                .get();
        collection.createIndex(idxExtension, optExtension);

        DBObject uidxRemoteName = BasicDBObjectBuilder.start(FIELD_FILESET, 1).add(FIELD_REMOTE_NAME, 1).get();
        DBObject optRemoteName = BasicDBObjectBuilder.start("name", "uidx_remoteName").add("unique", Boolean.TRUE)
                .get();
        collection.createIndex(uidxRemoteName, optRemoteName);

        DBObject uidxLocalName = BasicDBObjectBuilder.start(FIELD_FILESET, 1).add(FIELD_LOCAL_NAME, 1).get();
        DBObject optLocalName = BasicDBObjectBuilder.start("name", "uidx_localName").add("unique", Boolean.TRUE)
                .get();
        collection.createIndex(uidxLocalName, optLocalName);
    }

    /**
     * Convert the Mongo DBObject into the API equivalent
     */
    private FileData fromDBObject(DBObject fileDataObj) {
        FileData ret = new FileData();
        ret.setFileset((String) fileDataObj.get(FIELD_FILESET));
        ret.setRemoteName((String) fileDataObj.get(FIELD_REMOTE_NAME));
        ret.setLocalName((String) fileDataObj.get(FIELD_LOCAL_NAME));
        ret.setExtension((String) fileDataObj.get(FIELD_EXTENSION));
        ret.setEncoding((String) fileDataObj.get(FIELD_ENCODING));
        ret.setLocale((String) fileDataObj.get(FIELD_LOCALE));
        ret.setSize((Long) fileDataObj.get(FIELD_SIZE));
        ret.setRandomizer((Integer) fileDataObj.get(FIELD_RANDOMIZER));
        return ret;
    }

    @Override
    public void createNewFileData(FileData fileData) {
        DBObject fileDataObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileData.getFileset())
                .add(FIELD_REMOTE_NAME, fileData.getRemoteName()).add(FIELD_LOCAL_NAME, fileData.getLocalName())
                .add(FIELD_EXTENSION, fileData.getExtension()).add(FIELD_ENCODING, fileData.getEncoding())
                .add(FIELD_LOCALE, fileData.getLocale()).add(FIELD_SIZE, fileData.getSize())
                .add(FIELD_RANDOMIZER, fileData.getRandomizer()).get();
        WriteResult result = collection.insert(fileDataObj);

        if (logger.isDebugEnabled()) {
            logger.debug("Wrote FileData to collection: \n" + "   " + fileData + "\n" + "   Result: " + result);
        }
    }

    @Override
    public long fileCount(String fileset) {
        DBObject queryObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileset).get();
        return collection.count(queryObj);
    }

    /**
     * Count the number of files of the given type in a fileset
     */
    private long fileCount(String fileset, String extension) {
        DBObject queryObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileset).add(FIELD_EXTENSION, extension)
                .get();
        return collection.count(queryObj);
    }

    @Override
    public FileData findFile(String fileset, String remoteName) {
        DBObject queryObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileset)
                .add(FIELD_REMOTE_NAME, remoteName).get();
        DBObject resultObj = collection.findOne(queryObj);
        if (resultObj == null) {
            if (logger.isDebugEnabled()) {
                logger.debug("Did not find file '" + remoteName + "' in " + fileset);
            }
            return null;
        } else {
            if (logger.isDebugEnabled()) {
                logger.debug("Found file '" + remoteName + "' in " + fileset + ": " + resultObj);
            }
            return fromDBObject(resultObj);
        }
    }

    @Override
    public void removeFile(String fileset, String remoteName) {
        DBObject queryObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileset)
                .add(FIELD_REMOTE_NAME, remoteName).get();
        WriteResult result = collection.remove(queryObj);

        if (logger.isDebugEnabled()) {
            logger.debug("Removed " + fileset + "." + remoteName + " and hit " + result.getN() + " rows");
        }
    }

    @Override
    public FileData getRandomFile(String fileset) {
        long count = fileCount(fileset);
        if (count == 0L) {
            // There is nothing to choose from
            return null;
        }
        // Use a random number from 0 (inclusive) to 'count' (exclusive)
        int skip = (int) (Math.random() * (double) count);

        DBObject queryObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileset).get();
        DBCursor results = collection.find(queryObj).skip(skip).limit(1);
        if (results.size() == 0) {
            // No results
            return null;
        } else {
            DBObject fileDataObj = results.next();
            return fromDBObject(fileDataObj);
        }
    }

    @Override
    public FileData getRandomFile(String fileset, String extension) {
        long count = fileCount(fileset, extension);
        if (count == 0L) {
            // There is nothing to choose from
            return null;
        }
        // Use a random number from 0 (inclusive) to 'count' (exclusive)
        int skip = (int) (Math.random() * (double) count);

        DBObject queryObj = BasicDBObjectBuilder.start().add(FIELD_FILESET, fileset).add(FIELD_EXTENSION, extension)
                .get();
        DBCursor results = collection.find(queryObj).skip(skip).limit(1);
        if (results.size() == 0) {
            // No results
            return null;
        } else {
            DBObject fileDataObj = results.next();
            return fromDBObject(fileDataObj);
        }
    }
}