reactor.util.concurrent

Interface Sequence

All Superinterfaces:

java.util.function.LongSupplier

public interface Sequence
extends java.util.function.LongSupplier

Concurrent sequence class used for tracking the progress of the ring buffer and event processors. Support a number of concurrent operations including CAS and order writes.

Also attempts to be more efficient with regards to false sharing by adding padding around the volatile field.

Field Summary

Fields

Modifier and Type	Field and Description
static long	INITIAL_VALUE

Method Summary

Modifier and Type	Method and Description
long	addAndGet(long increment) Atomically add the supplied value.
boolean	compareAndSet(long expectedValue, long newValue) Perform a compare and set operation on the sequence.
long	getAsLong() Perform a volatile read of this sequence's value.
long	incrementAndGet() Atomically increment the sequence by one.
void	set(long value) Perform an ordered write of this sequence.
void	setVolatile(long value) Performs a volatile write of this sequence.

Field Detail

INITIAL_VALUE

static final long INITIAL_VALUE

See Also:

Constant Field Values

Method Detail

getAsLong

long getAsLong()

Perform a volatile read of this sequence's value.

Specified by:

getAsLong in interface java.util.function.LongSupplier

Returns:

The current value of the sequence.

set

void set(long value)

Perform an ordered write of this sequence. The intent is a Store/Store barrier between this write and any previous store.

Parameters:

value - The new value for the sequence.

setVolatile

void setVolatile(long value)

Performs a volatile write of this sequence. The intent is a Store/Store barrier between this write and any previous write and a Store/Load barrier between this write and any subsequent volatile read.

Parameters:

value - The new value for the sequence.

compareAndSet

boolean compareAndSet(long expectedValue,
                      long newValue)

Perform a compare and set operation on the sequence.

Parameters:

expectedValue - The expected current value.

newValue - The value to update to.

Returns:

true if the operation succeeds, false otherwise.

incrementAndGet

long incrementAndGet()

Atomically increment the sequence by one.

Returns:

The value after the increment

addAndGet

long addAndGet(long increment)

Atomically add the supplied value.

Parameters:

increment - The value to add to the sequence.

Returns:

The value after the increment.