Module is.codion.common.core

Package is.codion.common.state

Interface State

All Superinterfaces:

ObservableState, Observer<Boolean>

public interface State
extends ObservableState

A class encapsulating a boolean state.

 State state = State.state();

 ObservableState observable = state.observable();

 observer.addConsumer(this::onStateChange);

 state.set(true);
 state.set(false);

 boolean value = state.is();

A factory for State instances.

Listener management (add/remove) and state modifications are thread-safe

See Also:

• state()
• state(boolean)
• builder()

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	State.Builder	Builds a State instance.
static interface	State.Combination	A state which combines a number of states, either ANDing or ORing those together when determining its own state.
static interface	State.Group	A State.Group deactivates all other states when a state in the group is activated.

Method Summary

Modifier and Type	Method	Description
boolean	addValidator(Value.Validator<? super Boolean> validator)	Adds a validator to this State.
static State.Combination	and(ObservableState... observableStates)	Creates a new State.Combination instance using Conjunction.AND.
static State.Combination	and(Collection<? extends ObservableState> observableStates)	Creates a new State.Combination instance using Conjunction.AND.
static State.Builder	builder()
static State.Combination	combination(Conjunction conjunction, ObservableState... observableStates)	Creates a new State.Combination instance.
static State.Combination	combination(Conjunction conjunction, Collection<? extends ObservableState> observableStates)	Creates a new State.Combination instance.
static State.Group	group(State... states)	Creates a new State.Group instance, which guarantees that only a single state within the group is active at a time
static State.Group	group(Collection<State> states)	Creates a new State.Group instance, which guarantees that only a single state within the group is active at a time
void	link(State originalState)	Creates a bidirectional link between this and the given original state, so that changes in one are reflected in the other.
ObservableState	observable()	Returns an ObservableState notified each time the state changes
static State.Combination	or(ObservableState... observableStates)	Creates a new State.Combination instance using Conjunction.OR.
static State.Combination	or(Collection<? extends ObservableState> observableStates)	Creates a new State.Combination instance using Conjunction.OR.
static <T> ObservableState	present(Observable<T> observable)
boolean	removeValidator(Value.Validator<? super Boolean> validator)	Removes the given validator from this value
void	set(boolean value)	Sets the value
static State	state()	Creates a new 'false' State instance.
static State	state(boolean value)	Creates a new State instance.
void	toggle()	Toggles this state
void	unlink(State originalState)	Unlinks this state from the given original state
Value<Boolean>	value()

Methods inherited from interface is.codion.common.state.ObservableState

addConsumer, addListener, addWeakConsumer, addWeakListener, is, not, observer, removeConsumer, removeListener, removeWeakConsumer, removeWeakListener

Method Details

set

void set(boolean value)

Sets the value

Parameters:

value - the new value

toggle

void toggle()

Toggles this state

observable

ObservableState observable()

Returns an ObservableState notified each time the state changes

Returns:

an ObservableState notified each time the state changes

value

Value<Boolean> value()

Returns:

a Value instance representing this state

link

void link(State originalState)

Creates a bidirectional link between this and the given original state, so that changes in one are reflected in the other. Note that after a call to this method this state is the same as originalState.

Parameters:

originalState - the original state to link this state to

Throws:

IllegalStateException - in case the states are already linked or if a cycle is detected

IllegalArgumentException - in case the original state is not valid according to this states validators

unlink

void unlink(State originalState)

Unlinks this state from the given original state

Parameters:

originalState - the original value to unlink from this one

Throws:

IllegalStateException - in case the states are not linked

addValidator

boolean addValidator(Value.Validator<? super Boolean> validator)

Adds a validator to this State. Adding the same validator again has no effect.

Parameters:

validator - the validator

Returns:

true if this value did not already contain the specified validator

Throws:

IllegalArgumentException - in case the current value is invalid according to the validator

removeValidator

boolean removeValidator(Value.Validator<? super Boolean> validator)

Removes the given validator from this value

Parameters:

validator - the validator

Returns:

true if this value contained the specified validator

state

static State state()

Creates a new 'false' State instance.

Returns:

a new State instance

state

static State state(boolean value)

Creates a new State instance.

Parameters:

value - the initial state value

Returns:

a new State instance

builder

static State.Builder builder()

Returns:

a new State.Builder instance

present

static <T> ObservableState present(Observable<T> observable)

Returns:

an ObservableState active when the given observable has a value present, determined by Observable.optional().

combination

static State.Combination combination(Conjunction conjunction,
 ObservableState... observableStates)

Creates a new State.Combination instance.

Parameters:

conjunction - the conjunction to use

observableStates - the state observers to base this state combination on

Returns:

a new State.Combination instance

combination

static State.Combination combination(Conjunction conjunction,
 Collection<? extends ObservableState> observableStates)

Creates a new State.Combination instance.

Parameters:

conjunction - the conjunction to use

observableStates - the state observers to base this state combination on

Returns:

a new State.Combination instance

and

static State.Combination and(ObservableState... observableStates)

Creates a new State.Combination instance using Conjunction.AND.

Parameters:

observableStates - the state observers to base this state combination on

Returns:

a new State.Combination instance

and

static State.Combination and(Collection<? extends ObservableState> observableStates)

Creates a new State.Combination instance using Conjunction.AND.

Parameters:

observableStates - the state observers to base this state combination on

Returns:

a new State.Combination instance

or

static State.Combination or(ObservableState... observableStates)

Creates a new State.Combination instance using Conjunction.OR.

Parameters:

observableStates - the state observers to base this state combination on

Returns:

a new State.Combination instance

or

static State.Combination or(Collection<? extends ObservableState> observableStates)

Creates a new State.Combination instance using Conjunction.OR.

Parameters:

observableStates - the state observers to base this state combination on

Returns:

a new State.Combination instance

group

static State.Group group(State... states)

Creates a new State.Group instance, which guarantees that only a single state within the group is active at a time

Parameters:

states - the states to add to the group initially, not required

Returns:

a new State.Group instance

See Also:

• State.Group

group

static State.Group group(Collection<State> states)

Creates a new State.Group instance, which guarantees that only a single state within the group is active at a time

Parameters:

states - the states to add to the group initially

Returns:

a new State.Group instance

See Also:

• State.Group