Java MongoDB : Save image example

In this tutorial, we show you how to save an image file into MongoDB, via GridFS API. The GridFS APIs are able to serve other binary files as well, like video and music files.java

1. Save image

Code snippets to save an image file into MongoDB, under 「photo」 namespace, and assign a new 「filename」 for the saved image.mongodb

String newFileName = "mkyong-java-image";
    File imageFile = new File("c:\\JavaWebHosting.png");
    GridFS gfsPhoto = new GridFS(db, "photo");
    GridFSInputFile gfsFile = gfsPhoto.createFile(imageFile);
    gfsFile.setFilename(newFileName);
    gfsFile.save();

2. Get image

Code snippets to get the saved image by its 「filename」.ide

String newFileName = "mkyong-java-image";
    GridFS gfsPhoto = new GridFS(db, "photo");
     GridFSDBFile imageForOutput = gfsPhoto.findOne(newFileName);
    System.out.println(imageForOutput);

Output, the image is saved as following JSON format.this

{ 
    "_id" : 
    { 
        "$oid" : "4dc9511a14a7d017fee35746"
    } , 
    "chunkSize" : 262144 , 
    "length" : 22672 , 
    "md5" : "1462a6cfa27669af1d8d21c2d7dd1f8b" , 
    "filename" : "mkyong-java-image" , 
    "contentType" :  null  , 
    "uploadDate" : 
    { 
        "$date" : "2011-05-10T14:52:10Z"
    } , 
    "aliases" :  null 
}

Code snippets to get all the saved files from MongoDB and iterate it with DBCursor.spa

GridFS gfsPhoto = new GridFS(db, "photo");
    DBCursor cursor = gfsPhoto.getFileList();
    while (cursor.hasNext()) {
        System.out.println(cursor.next());
    }

4. Save into another image

Code snippets to get an image file from MongoDB and output it to another image file..net

String newFileName = "mkyong-java-image";
    GridFS gfsPhoto = new GridFS(db, "photo");
    GridFSDBFile imageForOutput = gfsPhoto.findOne(newFileName);
    imageForOutput.writeTo("c:\\JavaWebHostingNew.png"); //output to new file

5. Delete image

Code snippets to delete an image file.code

String newFileName = "mkyong-java-image";
    GridFS gfsPhoto = new GridFS(db, "photo");
    gfsPhoto.remove(gfsPhoto.findOne(newFileName));

Full Example

Full example to work with image, via Java MongoDB GridFS API. See comments for explanation.orm

package com.mkyong.core;

import java.io.File;
import java.io.IOException;
import java.net.UnknownHostException;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.Mongo;
import com.mongodb.MongoException;
import com.mongodb.gridfs.GridFS;
import com.mongodb.gridfs.GridFSDBFile;
import com.mongodb.gridfs.GridFSInputFile;

/**
 * Java MongoDB : Save image example
 * 
 */

public class SaveImageApp {
    public static void main(String[] args) {

        try {

            Mongo mongo = new Mongo("localhost", 27017);
            DB db = mongo.getDB("imagedb");
            DBCollection collection = db.getCollection("dummyColl");

            String newFileName = "mkyong-java-image";

            File imageFile = new File("c:\\JavaWebHosting.png");

            // create a "photo" namespace
            GridFS gfsPhoto = new GridFS(db, "photo");

            // get image file from local drive
            GridFSInputFile gfsFile = gfsPhoto.createFile(imageFile);

            // set a new filename for identify purpose
            gfsFile.setFilename(newFileName);

            // save the image file into mongoDB
            gfsFile.save();

            // print the result
            DBCursor cursor = gfsPhoto.getFileList();
            while (cursor.hasNext()) {
                System.out.println(cursor.next());
            }

            // get image file by it's filename
            GridFSDBFile imageForOutput = gfsPhoto.findOne(newFileName);

            // save it into a new image file
            imageForOutput.writeTo("c:\\JavaWebHostingNew.png");

            // remove the image file from mongoDB
            gfsPhoto.remove(gfsPhoto.findOne(newFileName));

            System.out.println("Done");

        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (MongoException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

At the end of the program, a new image file is created in 「c:\\JavaWebHostingNew.png「.ip

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