com.couchbase.lite.internal.utils

Class StateMachine<T extends Enum<T>>

java.lang.Object

com.couchbase.lite.internal.utils.StateMachine<T>

Type Parameters:

T - states.

public final class StateMachine<T extends Enum<T>>
extends Object

A simple state machine.

This class is not thread safe!

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StateMachine.Builder<S extends Enum<S>>

Method Summary

Modifier and Type	Method and Description
boolean	assertState(T... expected) Verify expected state.
boolean	setState(T nextState) Set the new state.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

toString

@NonNull
public String toString()

Overrides:

toString in class Object

assertState

@SafeVarargs
public final boolean assertState(@NonNull
                                              T... expected)

Verify expected state.

Parameters:

expected - expected states.

Returns:

true if the current state at the time of the call, is one of the expected states.

setState

public boolean setState(@NonNull
                        T nextState)

Set the new state. If it is legal to transition to the new state, from the current state, do so, returning the now-previous state. If the transition is illegal do nothing and return null.

Parameters:

nextState - the requested new state

Returns:

the previous state, if the transition succeeds; null otherwise.