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.

1. Save image

Code snippets to save an image file into MongoDB, under “

photo

” namespace, and assign a new “

filename

” for the saved image.

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

”.

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.

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

3. Print all saved images

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

DBCursor

.

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.

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.

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.

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

“.