public final class LuhnChecksumValidator
extends Object implements Parcelable, Validator



Validator that returns true if the number created by concatenating all given fields pass a Luhn algorithm checksum. All non-digits are ignored.

See SaveInfo.Builder.setValidator(Validator) for examples.

Summary

Inherited constants

From interface android.os.Parcelable

int CONTENTS_FILE_DESCRIPTOR

Descriptor bit used with describeContents(): indicates that the Parcelable object's flattened representation includes a file descriptor.

int PARCELABLE_WRITE_RETURN_VALUE

Flag for use with writeToParcel(Parcel, int): the object being written is a return value, that is the result of a function such as "Parcelable someFunction()", "void someFunction(out Parcelable)", or "void someFunction(inout Parcelable)".

Fields

public static final Creator<LuhnChecksumValidator> CREATOR

Public constructors

LuhnChecksumValidator(AutofillId... ids)

Default constructor.

Public methods

int describeContents()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation.

String toString()

Returns a string representation of the object.

void writeToParcel(Parcel parcel, int flags)

Flatten this object in to a Parcel.

Inherited methods

From class java.lang.Object

Object clone()

Creates and returns a copy of this object.

boolean equals(Object obj)

Indicates whether some other object is "equal to" this one.

void finalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

final Class<?> getClass()

Returns the runtime class of this Object.

int hashCode()

Returns a hash code value for the object.

final void notify()

Wakes up a single thread that is waiting on this object's monitor.

final void notifyAll()

Wakes up all threads that are waiting on this object's monitor.

String toString()

Returns a string representation of the object.

final void wait(long timeoutMillis, int nanos)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void wait(long timeoutMillis)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void wait()

Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

From interface android.os.Parcelable

abstract int describeContents()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation.

abstract void writeToParcel(Parcel dest, int flags)

Flatten this object in to a Parcel.

Fields

Public constructors

LuhnChecksumValidator

public LuhnChecksumValidator (AutofillId... ids)

Default constructor.

Parameters
ids AutofillId: id of fields that comprises the number to be checked.
This value cannot be null.

Public methods

describeContents

public int describeContents ()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. For example, if the object will include a file descriptor in the output of writeToParcel(android.os.Parcel, int), the return value of this method must include the CONTENTS_FILE_DESCRIPTOR bit.

Returns
int a bitmask indicating the set of special object types marshaled by this Parcelable object instance.
Value is either 0 or

toString

public String toString ()

Returns a string representation of the object.

Returns
String a string representation of the object.

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Last updated 2026-02-13 UTC.