cc.acs.mongofs.gridfs.GridFS.java Source code

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Here is the source code for cc.acs.mongofs.gridfs.GridFS.java

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// GridFS.java

/**
 *      Copyright (C) 2008 10gen Inc.
 *
 *   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 cc.acs.mongofs.gridfs;

import java.io.*;
import java.util.*;

import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.BasicDBObjectBuilder;
import com.mongodb.BasicDBObject;
import com.mongodb.DBCursor;

import org.bson.types.*;

/**
 *  Implementation of GridFS v1.0
 *
 *  <a href="http://www.mongodb.org/display/DOCS/GridFS+Specification">GridFS 1.0 spec</a>
 * 
 * @dochub gridfs
 */
public class GridFS {

    public static final int DEFAULT_CHUNKSIZE = 256 * 1024;

    // --------------------------
    // ------ constructors -------
    // --------------------------

    /**
     * Creates a GridFS instance for the specified bucket
     * in the given database.
     *
     * @param db database to work with
     * @param bucket bucket to use in the given database
     */
    public GridFS(DB db, String bucket) {
        _db = db;
        _bucketName = bucket;

        _filesCollection = _db.getCollection(_bucketName + ".files");
        _chunkCollection = _db.getCollection(_bucketName + ".chunks");

        _chunkCollection.ensureIndex(BasicDBObjectBuilder.start().add("files_id", 1).add("n", 1).get());

        _filesCollection.setObjectClass(GridFSDBFile.class);
    }

    // --------------------------
    // ------ utils       -------
    // --------------------------

    /**
     *   Returns a cursor for this filestore
     *
     * @return cursor of file objects
     */
    public DBCursor getFileList() {
        return _filesCollection.find().sort(new BasicDBObject("filename", 1));
    }

    /**
     *   Returns a cursor for this filestore
     *
     * @param query filter to apply
     * @return cursor of file objects
     */
    public DBCursor getFileList(DBObject query) {
        return _filesCollection.find(query).sort(new BasicDBObject("filename", 1));
    }

    // --------------------------
    // ------ reading     -------
    // --------------------------

    public GridFSDBFile find(ObjectId id) {
        return findOne(id);
    }

    public GridFSDBFile findOne(ObjectId id) {
        return findOne(new BasicDBObject("_id", id));
    }

    public GridFSDBFile findOne(String filename) {
        return findOne(new BasicDBObject("filename", filename));
    }

    public GridFSDBFile findOne(DBObject query) {
        return _fix(_filesCollection.findOne(query));
    }

    public List<GridFSDBFile> find(String filename) {
        return find(new BasicDBObject("filename", filename));
    }

    public List<GridFSDBFile> find(DBObject query) {
        List<GridFSDBFile> files = new ArrayList<GridFSDBFile>();

        DBCursor c = _filesCollection.find(query);
        while (c.hasNext()) {
            files.add(_fix(c.next()));
        }
        return files;
    }

    private GridFSDBFile _fix(Object o) {
        if (o == null)
            return null;

        if (!(o instanceof GridFSDBFile))
            throw new RuntimeException("somehow didn't get a GridFSDBFile");

        GridFSDBFile f = (GridFSDBFile) o;
        f._fs = this;
        return f;
    }

    // --------------------------
    // ------ remove      -------
    // --------------------------

    public void remove(ObjectId id) {
        _filesCollection.remove(new BasicDBObject("_id", id));
        _chunkCollection.remove(new BasicDBObject("files_id", id));
    }

    public void remove(String filename) {
        remove(new BasicDBObject("filename", filename));
    }

    public void remove(DBObject query) {
        for (GridFSDBFile f : find(query)) {
            f.remove();
        }
    }

    // --------------------------
    // ------ writing     -------
    // --------------------------

    /**
     * after calling this method, you have to call save() on the GridFSInputFile file
     */
    public GridFSInputFile createFile(byte[] data) {
        return createFile(new ByteArrayInputStream(data));
    }

    /**
     * after calling this method, you have to call save() on the GridFSInputFile file
     */
    public GridFSInputFile createFile(File f) throws IOException {
        return createFile(new FileInputStream(f), f.getName());
    }

    /**
     * after calling this method, you have to call save() on the GridFSInputFile file
     */
    public GridFSInputFile createFile(InputStream in) {
        return createFile(in, null);
    }

    /**
     * after calling this method, you have to call save() on the GridFSInputFile file
     * on that, you can call setFilename, setContentType and control meta data by modifying the 
     *   result of getMetaData
     */
    public GridFSInputFile createFile(InputStream in, String filename) {
        return new GridFSInputFile(this, in, filename);
    }

    // --------------------------
    // ------ members     -------
    // --------------------------

    public String getBucketName() {
        return _bucketName;
    }

    public DB getDB() {
        return _db;
    }

    protected final DB _db;
    protected final String _bucketName;
    protected final DBCollection _filesCollection;
    protected final DBCollection _chunkCollection;

}