Package com.example.breeze_seas

Class ImageDB

java.lang.Object

com.example.breeze_seas.ImageDB

public class ImageDB
extends Object

Provides Firestore database operations for image documents.

This class is responsible for managing image records stored in the images collection. It supports generating new image document IDs, saving image data, loading image data, deleting images, and listening for real-time updates from Firestore.

All methods are static because this class acts as a utility-style database access layer for image-related operations.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ImageDB.ImageMutationCallback	Callback interface for image write and delete operations.
static interface	ImageDB.ImagesChangedCallback	Callback interface for real-time image collection updates.
static interface	ImageDB.LoadImageCallback	Callback interface for loading a single image.

Method Summary

Modifier and Type	Method	Description
static void	deleteImage(String imageDocId, ImageDB.ImageMutationCallback callback)	Deletes images/{imageDocId} from the Firestore images collection.
static String	genNewId()	Generates a new document ID from the Firestore images collection.
static void	loadImage(String imageDocId, ImageDB.LoadImageCallback callback)	Loads a Base64 image string from images/{imageDocId} and constructs an Image object from the retrieved data.
static void	saveImage(Image image, ImageDB.ImageMutationCallback callback)	Saves an image into images/{imageDocId}.
static void	startImagesListen(ImageDB.ImagesChangedCallback callback)	Attaches a real-time listener to the images collection.
static void	stopImagesListen()	Detaches the real-time images listener if one is currently active.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

genNewId

public static String genNewId()

Generates a new document ID from the Firestore images collection.

Returns:

the newly generated document ID

saveImage

public static void saveImage(Image image,
 ImageDB.ImageMutationCallback callback)

Saves an image into images/{imageDocId}.

The image data is stored under the data field, and the current timestamp is stored under updatedTimestamp. Existing fields are preserved because the write uses merge semantics.

Parameters:

image - the image object to save

callback - the callback to invoke after the Firestore write succeeds or fails

loadImage

public static void loadImage(String imageDocId,
 ImageDB.LoadImageCallback callback)

Loads a Base64 image string from images/{imageDocId} and constructs an Image object from the retrieved data.

Parameters:

imageDocId - the document ID in the images collection

callback - the callback that receives the loaded image or an error

startImagesListen

public static void startImagesListen(ImageDB.ImagesChangedCallback callback)

Attaches a real-time listener to the images collection.

For each document change received from Firestore, the corresponding callback method is invoked based on whether the image was added, modified, or removed.

Parameters:

callback - receives individual change events or listener errors

stopImagesListen

public static void stopImagesListen()

Detaches the real-time images listener if one is currently active.

This should be called when the associated screen or component is being torn down in order to avoid memory leaks and unnecessary Firestore updates.

deleteImage

public static void deleteImage(String imageDocId,
 ImageDB.ImageMutationCallback callback)

Deletes images/{imageDocId} from the Firestore images collection.

Parameters:

imageDocId - the document ID in the images collection

callback - the callback to invoke after the delete succeeds or fails