Transaction

public class Transaction extends Object

A Transaction is passed to a Function to provide the methods to read and write data within the transaction context.

Subclassing Note: Firestore classes are not meant to be subclassed except for use in test mocks. Subclassing is not supported in production code and new SDK releases may break code that does so.

See Also

• runTransaction(Function)

Nested Class Summary

interface

Transaction.Function<TResult>

An interface for providing code to be executed within a transaction context.

Public Method Summary

Transaction	delete(DocumentReference documentRef) Deletes the document referred to by the provided DocumentReference.
DocumentSnapshot	get(DocumentReference documentRef) Reads the document referenced by this DocumentReference
Transaction	set(DocumentReference documentRef, Object data) Overwrites the document referred to by the provided DocumentReference.
Transaction	set(DocumentReference documentRef, Object data, SetOptions options) Writes to the document referred to by the provided DocumentReference.
Transaction	update(DocumentReference documentRef, Map<String, Object> data) Updates fields in the document referred to by the provided DocumentReference.
Transaction	update(DocumentReference documentRef, String field, Object value, Object... moreFieldsAndValues) Updates fields in the document referred to by the provided DocumentReference.
Transaction	update(DocumentReference documentRef, FieldPath fieldPath, Object value, Object... moreFieldsAndValues) Updates fields in the document referred to by the provided DocumentReference.

Inherited Method Summary

From class java.lang.Object

Object	clone()
boolean	equals(Object arg0)
void	finalize()
final Class<?>	getClass()
int	hashCode()
final void	notify()
final void	notifyAll()
String	toString()
final void	wait(long arg0, int arg1)
final void	wait(long arg0)
final void	wait()

Public Methods

public Transaction delete (DocumentReference documentRef)

Deletes the document referred to by the provided DocumentReference.

Parameters

documentRef	The DocumentReference to delete.

Returns

• This Transaction instance. Used for chaining method calls.

public DocumentSnapshot get (DocumentReference documentRef)

Reads the document referenced by this DocumentReference

Parameters

documentRef	The DocumentReference to read.

Returns

• The contents of the Document at this DocumentReference.

Throws

FirebaseFirestoreException

public Transaction set (DocumentReference documentRef, Object data)

Overwrites the document referred to by the provided DocumentReference. If the document does not yet exist, it will be created. If a document already exists, it will be overwritten.

Parameters

documentRef	The DocumentReference to overwrite.
data	The data to write to the document (e.g. a Map or a POJO containing the desired document contents).

Returns

• This Transaction instance. Used for chaining method calls.

public Transaction set (DocumentReference documentRef, Object data, SetOptions options)

Writes to the document referred to by the provided DocumentReference. If the document does not yet exist, it will be created. If you pass SetOptions, the provided data can be merged into an existing document.

Parameters

documentRef	The DocumentReference to overwrite.
data	The data to write to the document (e.g. a Map or a POJO containing the desired document contents).
options	An object to configure the set behavior.

Returns

• This Transaction instance. Used for chaining method calls.

public Transaction update (DocumentReference documentRef, Map<String, Object> data)

Updates fields in the document referred to by the provided DocumentReference. If no document exists yet, the update will fail.

Parameters

documentRef	The DocumentReference to update.
data	A map of field / value pairs to update. Fields can contain dots to reference nested fields within the document.

Returns

• This Transaction instance. Used for chaining method calls.

public Transaction update (DocumentReference documentRef, String field, Object value, Object... moreFieldsAndValues)

Updates fields in the document referred to by the provided DocumentReference. If no document exists yet, the update will fail.

Parameters

documentRef	The DocumentReference to update.
field	The first field to update. Fields can contain dots to reference a nested field within the document.
value	The first value
moreFieldsAndValues	Additional field/value pairs.

Returns

• This Transaction instance. Used for chaining method calls.

public Transaction update (DocumentReference documentRef, FieldPath fieldPath, Object value, Object... moreFieldsAndValues)

Updates fields in the document referred to by the provided DocumentReference. If no document exists yet, the update will fail.

Parameters

documentRef	The DocumentReference to update.
fieldPath	The first field to update.
value	The first value
moreFieldsAndValues	Additional field/value pairs.

Returns

• This Transaction instance. Used for chaining method calls.