io.debezium.crdt

Interface PNCounter

All Superinterfaces:

Count, GCount, GCounter, PNCount

All Known Subinterfaces:

DeltaCounter

All Known Implementing Classes:

StateBasedPNCounter, StateBasedPNDeltaCounter

@NotThreadSafe
public interface PNCounter
extends PNCount, GCounter

A simple counter that maintains a single changing value by separately tracking the positive and negative changes. It is inspired by the conflict-free replicated data type (CRDT) P-N Counter. The semantics ensure the value converges toward the global number of increments minus the number of decrements. The global total can be calculated by merging all the replicated instances, without regard to order of merging.

Method Summary

Modifier and Type	Method and Description
PNCounter	decrement() Decrement the counter and get the result.
long	decrementAndGet() Decrement the counter and get the result.
long	getAndDecrement() Decrement the counter and get the result.
PNCounter	increment() Increment the counter and get the result.
PNCounter	merge(Count other) Merge the supplied counter into this counter.

Methods inherited from interface io.debezium.crdt.PNCount

get, getDecrement

Methods inherited from interface io.debezium.crdt.GCounter

getAndIncrement, incrementAndGet

Methods inherited from interface io.debezium.crdt.GCount

getIncrement

Method Detail

increment

PNCounter increment()

Increment the counter and get the result.

Specified by:

increment in interface GCounter

Returns:

this instance so methods can be chained together; never null

decrement

PNCounter decrement()

Decrement the counter and get the result.

Returns:

this instance so methods can be chained together; never null

decrementAndGet

long decrementAndGet()

Decrement the counter and get the result.

Returns:

the current result after decrementing

getAndDecrement

long getAndDecrement()

Decrement the counter and get the result.

Returns:

the current result before decrementing

merge

PNCounter merge(Count other)

Merge the supplied counter into this counter.

Specified by:

merge in interface GCounter

Parameters:

other - the other counter to merge into this one; may be null

Returns:

this counter so that methods can be chained