IMPORTANT: In July 2025, we stopped releasing new versions of KTX modules, and we removed the KTX libraries from the Firebase Android BoM (v34.0.0). If you use KTX APIs from the previously released KTX modules, we recommend that you migrate your app to use KTX APIs from the main modules instead. For details, see the FAQ about this initiative.

ServerValue

class ServerValue

Contains placeholder values to use when writing data to the Firebase Database.

Summary

Constants
`const (Mutable)Map<String!, String!>`	`TIMESTAMP` A placeholder value for auto-populating the current timestamp (time since the Unix epoch, in milliseconds) by the Firebase Database servers.

Public constructors
`ServerValue()`

Public functions
`java-static Any`	`increment(delta: Long)` Returns a placeholder value that can be used to atomically increment the current database value by the provided delta.
`java-static Any`	`increment(delta: Double)` Returns a placeholder value that can be used to atomically increment the current database value by the provided delta.

Constants

TIMESTAMP

const val TIMESTAMP: (Mutable)Map<String!, String!>

A placeholder value for auto-populating the current timestamp (time since the Unix epoch, in milliseconds) by the Firebase Database servers.

Public constructors

ServerValue

ServerValue()

Public functions

increment

java-static fun increment(delta: Long): Any

Returns a placeholder value that can be used to atomically increment the current database value by the provided delta.

The delta must be an long or a double value. If the current value is not a number, or if the database value does not yet exist, the transformation will set the database value to the delta value. If either the delta value or the existing value are doubles, both values will be interpreted as doubles. Double arithmetic and representation of double values follow IEEE 754 semantics. If there is positive/negative integer overflow, the sum is calculated as a double.

Parameters
`delta: Long`	the amount to modify the current value atomically.

Returns
`Any`	a placeholder value for modifying data atomically server-side.

increment

java-static fun increment(delta: Double): Any

Returns a placeholder value that can be used to atomically increment the current database value by the provided delta.

The delta must be an long or a double value. If the current value is not an integer or double, or if the data does not yet exist, the transformation will set the data to the delta value. If either of the delta value or the existing data are doubles, both values will be interpreted as doubles. Double arithmetic and representation of double values follow IEEE 754 semantics. If there is positive/negative integer overflow, the sum is calculated as a a double.

Parameters
`delta: Double`	the amount to modify the current value atomically.

Returns
`Any`	a placeholder value for modifying data atomically server-side.