org.basket3.filesystem.dao.GAEBucketDao.java Source code

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Here is the source code for org.basket3.filesystem.dao.GAEBucketDao.java

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/**
 *    
 * Copyright 2013 Pagecrumb
 *
 * 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.basket3.filesystem.dao;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.basket3.bo.Bucket;
import org.basket3.common.S3Exception;
import org.basket3.dao.BucketDao;
import org.basket3.filesystem.bo.GsonSerializer;
import org.bson.types.ObjectId;
import org.json.simple.JSONObject;

import com.google.inject.Singleton;
import com.pagecrumb.mungo.Mungo;
import com.pagecrumb.mungo.collection.DBCollection;
import com.pagecrumb.mungo.collection.DBObject;
import com.pagecrumb.mungo.entity.BasicDBObject;
import com.pagecrumb.mungo.serializer.ObjectSerializer;

/**
 * An implementation of <code>BucketDao</code> that uses the the GAE Datastore to
 * index and manage the bucket's meta data.
 * 
 * @author Kerby Martino <kerbymart@gmail.com>
 */
@Singleton
public class GAEBucketDao extends GAEFileBase implements BucketDao {

    private Log logger;
    private ObjectSerializer serializer;
    private DBCollection _buckets;

    public GAEBucketDao() {
        super();
        logger = LogFactory.getLog(this.getClass());
        logger.debug("FileBucketDao created");
        serializer = new GsonSerializer();
        _buckets = new Mungo().getDB("S3").getCollection("Bucket");
    }

    /**
     * This method will load the bucket from a Java serialized file.
     * 
     * @param bucket
     *            The name of the bucket to load.
     * @throws DataAccessResourceFailureException
     *             General failure serializing the bucket.
     */
    public Bucket loadBucket(String bucket) throws S3Exception {
        logger.info("Loading bucket name=" + bucket);
        Bucket theBucket = null;
        try {
            BasicDBObject query = new BasicDBObject("name", bucket);
            DBObject obj = _buckets.findOne(query);
            if (obj != null) {
                return obj.as(Bucket.class);
            }
        } catch (Exception e) {
            throw new S3Exception("Could not find Bucket: " + bucket);
        }
        return theBucket;
    }

    /**
     * This method will remove a Java serialized file representing the bucket.
     * 
     * @param bucket
     *            The name of the bucket to remove.
     * @throws DataAccessResourceFailureException
     *             General failure removing the bucket.
     */
    public void removeBucket(Bucket bucket) throws S3Exception {
        try {
            BasicDBObject query = new BasicDBObject("name", bucket.getName());
            boolean isOk = (Boolean) _buckets.remove(query).getLastError().get("ok");
            if (!isOk) {
                throw new S3Exception("Cannot remove Bucket: " + bucket.getName());
            }
            ;
        } catch (Exception e) {
            e.printStackTrace();
            throw new S3Exception("Could not find Bucket: " + bucket);
        }
    }

    /**
     * This method will store the bucket as a Java serialized file.
     * 
     * @param bucket
     *            The bucket to store.
     * @throws DataAccessResourceFailureException
     *             General failure serializing the bucket.
     */
    public void storeBucket(Bucket bucket) throws S3Exception {
        try {
            ObjectId id = new ObjectId();
            _buckets.insert(new BasicDBObject(serializer.serialize(bucket)).append("_id", id));
        } catch (Exception e) {
            // TODO: handle exception
        }
    }

    private void toJSONStringPrint(DBObject obj) {
        JSONObject json = new JSONObject();
        json.putAll(obj.toMap());
        logger.info(json.toJSONString());
    }
}