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

A simple state machine.

This machine 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	checkState(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

checkState

@SafeVarargs
public final boolean checkState(@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 final 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 transtion succeeds; null otherwise.