Create a Cloud Storage reference on Android

Your files are stored in aCloud Storage bucket. Thefiles in this bucket are presented in a hierarchical structure, just like thefile system on your local hard disk, or the data in theFirebase Realtime Database.By creating a reference to a file, your app gains access to it. These referencescan then be used to upload or download data, get or update metadata or deletethe file. A reference can either point to a specific file or to a higher levelnode in the hierarchy.

If you've used theFirebase Realtime Database, these paths shouldseem very familiar to you. However, your file data is stored inCloud Storage,not in theRealtime Database.

Create a Reference

Create a reference to upload, download, or delete a file,or to get or update its metadata. A referencecan be thought of as a pointer to a file in the cloud. References arelightweight, so you can create as many as you need. They are also reusable formultiple operations.

Create a reference using theFirebaseStorage singleton instance andcalling itsgetReference() method.

Kotlin

// Create a storage reference from our appvarstorageRef=storage.reference

Java

// Create a storage reference from our appStorageReferencestorageRef=storage.getReference();

Next, you can create a reference to a location lower in the tree,say"images/space.jpg" by using thechild() method on an existing reference.

Kotlin

// Create a child reference// imagesRef now points to "images"varimagesRef:StorageReference?=storageRef.child("images")// Child references can also take paths// spaceRef now points to "images/space.jpg// imagesRef still points to "images"varspaceRef=storageRef.child("images/space.jpg")

Java

// Create a child reference// imagesRef now points to "images"StorageReferenceimagesRef=storageRef.child("images");// Child references can also take paths// spaceRef now points to "images/space.jpg// imagesRef still points to "images"StorageReferencespaceRef=storageRef.child("images/space.jpg");

Navigate with References

You can also use thegetParent() andgetRoot() methods to navigate up in ourfile hierarchy.getParent() navigates up one level,whilegetRoot() navigates all the way to the top.

Kotlin

// parent allows us to move our reference to a parent node// imagesRef now points to 'images'imagesRef=spaceRef.parent// root allows us to move all the way back to the top of our bucket// rootRef now points to the rootvalrootRef=spaceRef.root

Java

// getParent allows us to move our reference to a parent node// imagesRef now points to 'images'imagesRef=spaceRef.getParent();// getRoot allows us to move all the way back to the top of our bucket// rootRef now points to the rootStorageReferencerootRef=spaceRef.getRoot();

child(),getParent(), andgetRoot() can be chained together multipletimes, as each returns a reference. But callinggetRoot().getParent() returnsnull.

Kotlin

// References can be chained together multiple times// earthRef points to 'images/earth.jpg'valearthRef=spaceRef.parent?.child("earth.jpg")// nullRef is null, since the parent of root is nullvalnullRef=spaceRef.root.parent

Java

// References can be chained together multiple times// earthRef points to 'images/earth.jpg'StorageReferenceearthRef=spaceRef.getParent().child("earth.jpg");// nullRef is null, since the parent of root is nullStorageReferencenullRef=spaceRef.getRoot().getParent();

Reference Properties

You can inspect references to better understand the files they point tousing thegetPath(),getName(), andgetBucket() methods. These methodsget the file's full path, name and bucket.

Kotlin

// Reference's path is: "images/space.jpg"// This is analogous to a file path on diskspaceRef.path// Reference's name is the last segment of the full path: "space.jpg"// This is analogous to the file namespaceRef.name// Reference's bucket is the name of the storage bucket that the files are stored inspaceRef.bucket

Java

// Reference's path is: "images/space.jpg"// This is analogous to a file path on diskspaceRef.getPath();// Reference's name is the last segment of the full path: "space.jpg"// This is analogous to the file namespaceRef.getName();// Reference's bucket is the name of the storage bucket that the files are stored inspaceRef.getBucket();

Limitations on References

Reference paths and names can contain any sequence of valid Unicode characters,but certain restrictions are imposed including:

  1. Total length of reference.fullPath must be between 1 and 1024 bytes when UTF-8 encoded.
  2. No Carriage Return or Line Feed characters.
  3. Avoid using#,[,],*, or?, as these do not work well withother tools such as theFirebase Realtime Databaseorgsutil.

Full Example

Kotlin

// Points to the root referencestorageRef=storage.reference// Points to "images"imagesRef=storageRef.child("images")// Points to "images/space.jpg"// Note that you can use variables to create child valuesvalfileName="space.jpg"spaceRef=imagesRef.child(fileName)// File path is "images/space.jpg"valpath=spaceRef.path// File name is "space.jpg"valname=spaceRef.name// Points to "images"imagesRef=spaceRef.parent

Java

// Points to the root referencestorageRef=storage.getReference();// Points to "images"imagesRef=storageRef.child("images");// Points to "images/space.jpg"// Note that you can use variables to create child valuesStringfileName="space.jpg";spaceRef=imagesRef.child(fileName);// File path is "images/space.jpg"Stringpath=spaceRef.getPath();// File name is "space.jpg"Stringname=spaceRef.getName();// Points to "images"imagesRef=spaceRef.getParent();

Next, let's learn how toupload files toCloud Storage.

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Last updated 2026-02-18 UTC.