Package org.apache.pekko.actor.typed.javadsl

Class BehaviorBuilder<T>

java.lang.Object

org.apache.pekko.actor.typed.javadsl.BehaviorBuilder<T>

Type Parameters:

T - the common superclass of all supported messages.

public final class BehaviorBuilder<T>
extends Object

Immutable builder used for creating a Behavior by 'chaining' message and signal handlers.

When handling a message or signal, this Behavior will consider all handlers in the order they were added, looking for the first handler for which both the type and the (optional) predicate match.

Akka org.apache.pekko.japi.function lambda types are used throughout to allow handlers to throw checked exceptions (which will fail the actor).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BehaviorBuilder.Case$

Constructor Summary

Constructors

Constructor	Description
BehaviorBuilder()

Method Summary

Modifier and Type	Method	Description
Behavior<T>	build()	Build a Behavior from the current state of the builder
static <T> BehaviorBuilder<T>	create()
BehaviorBuilder<T>	onAnyMessage(Function<T,Behavior<T>> handler)	Add a new case to the message handling matching any message.
<M extends T> BehaviorBuilder<T>	onMessage(Class<M> type, Function<M,Behavior<T>> handler)	Add a new case to the message handling.
<M extends T> BehaviorBuilder<T>	onMessage(Class<M> type, Predicate<M> test, Function<M,Behavior<T>> handler)	Add a new predicated case to the message handling.
BehaviorBuilder<T>	onMessageEquals(T msg, Creator<Behavior<T>> handler)	Add a new case to the message handling matching equal messages.
<M extends T> BehaviorBuilder<T>	onMessageUnchecked(Class<? extends T> type, Function<M,Behavior<T>> handler)	Add a new case to the message handling without compile time type check.
<M extends Signal> BehaviorBuilder<T>	onSignal(Class<M> type, Function<M,Behavior<T>> handler)	Add a new case to the signal handling.
<M extends Signal> BehaviorBuilder<T>	onSignal(Class<M> type, Predicate<M> test, Function<M,Behavior<T>> handler)	Add a new predicated case to the signal handling.
BehaviorBuilder<T>	onSignalEquals(Signal signal, Creator<Behavior<T>> handler)	Add a new case to the signal handling matching equal signals.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

BehaviorBuilder

public BehaviorBuilder()

Method Details

create

public static <T> BehaviorBuilder<T> create()

Returns:

new empty immutable behavior builder.

build

public Behavior<T> build()

Build a Behavior from the current state of the builder

onMessage

public <M extends T> BehaviorBuilder<T> onMessage(Class<M> type,
 Function<M,Behavior<T>> handler)

Add a new case to the message handling.

Parameters:

type - type of message to match

handler - action to apply if the type matches

Returns:

a new behavior builder with the specified handling appended

onMessage

public <M extends T> BehaviorBuilder<T> onMessage(Class<M> type,
 Predicate<M> test,
 Function<M,Behavior<T>> handler)

Add a new predicated case to the message handling.

Parameters:

type - type of message to match

test - a predicate that will be evaluated on the argument if the type matches

handler - action to apply if the type matches and the predicate returns true

Returns:

a new behavior builder with the specified handling appended

onMessageUnchecked

public <M extends T> BehaviorBuilder<T> onMessageUnchecked(Class<? extends T> type,
 Function<M,Behavior<T>> handler)

Add a new case to the message handling without compile time type check.

Should normally not be used, but when matching on class with generic type argument it can be useful, e.g. List.class and (List<String> list) -> {...}

Parameters:

type - type of message to match

handler - action to apply when the type matches

Returns:

a new behavior builder with the specified handling appended

onMessageEquals

public BehaviorBuilder<T> onMessageEquals(T msg,
 Creator<Behavior<T>> handler)

Add a new case to the message handling matching equal messages.

Parameters:

msg - the message to compare to

handler - action to apply when the message matches

Returns:

a new behavior builder with the specified handling appended

onAnyMessage

public BehaviorBuilder<T> onAnyMessage(Function<T,Behavior<T>> handler)

Add a new case to the message handling matching any message. Subsequent onMessage clauses will never see any messages.

Parameters:

handler - action to apply for any message

Returns:

a new behavior builder with the specified handling appended

onSignal

public <M extends Signal> BehaviorBuilder<T> onSignal(Class<M> type,
 Function<M,Behavior<T>> handler)

Add a new case to the signal handling.

Parameters:

type - type of signal to match

handler - action to apply if the type matches

Returns:

a new behavior builder with the specified handling appended

onSignal

public <M extends Signal> BehaviorBuilder<T> onSignal(Class<M> type,
 Predicate<M> test,
 Function<M,Behavior<T>> handler)

Add a new predicated case to the signal handling.

Parameters:

type - type of signals to match

test - a predicate that will be evaluated on the argument if the type matches

handler - action to apply if the type matches and the predicate returns true

Returns:

a new behavior builder with the specified handling appended

onSignalEquals

public BehaviorBuilder<T> onSignalEquals(Signal signal,
 Creator<Behavior<T>> handler)

Add a new case to the signal handling matching equal signals.

Parameters:

signal - the signal to compare to

handler - action to apply when the message matches

Returns:

a new behavior builder with the specified handling appended