Package org.axonframework.commandhandling.gateway

Class DefaultCommandGateway

java.lang.Object

org.axonframework.commandhandling.gateway.AbstractCommandGateway

org.axonframework.commandhandling.gateway.DefaultCommandGateway

All Implemented Interfaces:

CommandGateway, MessageDispatchInterceptorSupport<CommandMessage<?>>

public class DefaultCommandGateway
extends AbstractCommandGateway
implements CommandGateway

Default implementation of the CommandGateway interface. It allow configuration of a RetryScheduler and CommandDispatchInterceptors. The Retry Scheduler allows for Command to be automatically retried when a non-transient exception occurs. The Command Dispatch Interceptors can intercept and alter command dispatched on this specific gateway. Typically, this would be used to add gateway specific meta data to the Command.

Since:

2.0

Author:

Allard Buijze

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DefaultCommandGateway.Builder	Builder class to instantiate a DefaultCommandGateway.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	DefaultCommandGateway(DefaultCommandGateway.Builder builder)	Instantiate a DefaultCommandGateway based on the fields contained in the DefaultCommandGateway.Builder.

Method Summary

Modifier and Type	Method	Description
static DefaultCommandGateway.Builder	builder()	Instantiate a Builder to be able to create a DefaultCommandGateway.
Registration	registerDispatchInterceptor(MessageDispatchInterceptor<? super CommandMessage<?>> dispatchInterceptor)	Registers a command dispatch interceptor within a CommandGateway.
<C, R> void	send(C command, CommandCallback<? super C,? super R> callback)	Sends the given command, and invokes the callback when the command is processed.
<R> CompletableFuture<R>	send(Object command)	Sends the given command and returns a CompletableFuture immediately, without waiting for the command to execute.
<R> R	sendAndWait(Object command)	Sends the given command and waits for its execution to complete, or until the waiting thread is interrupted.
<R> R	sendAndWait(Object command, long timeout, TimeUnit unit)	Sends the given command and waits for its execution to complete, or until the given timeout has expired, or the waiting thread is interrupted.

Methods inherited from class org.axonframework.commandhandling.gateway.AbstractCommandGateway

getCommandBus, processInterceptors, sendAndForget

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.axonframework.commandhandling.gateway.CommandGateway

send, sendAndWait, sendAndWait

Constructor Details

DefaultCommandGateway

protected DefaultCommandGateway(DefaultCommandGateway.Builder builder)

Instantiate a DefaultCommandGateway based on the fields contained in the DefaultCommandGateway.Builder.

Will assert that the CommandBus is not null and will throw an AxonConfigurationException if this is the case.

Parameters:

builder - the DefaultCommandGateway.Builder used to instantiate a DefaultCommandGateway instance

Method Details

builder

public static DefaultCommandGateway.Builder builder()

Instantiate a Builder to be able to create a DefaultCommandGateway.

The dispatchInterceptors are defaulted to an empty list. The CommandBus is a hard requirement and as such should be provided.

Returns:

a Builder to be able to create a DefaultCommandGateway

send

public <C,
R> void send(@Nonnull
 C command,
 @Nonnull
 CommandCallback<? super C,? super R> callback)

Description copied from class: AbstractCommandGateway

Sends the given command, and invokes the callback when the command is processed.

Specified by:

send in interface CommandGateway

Overrides:

send in class AbstractCommandGateway

Type Parameters:

R - The type of response expected from the command

Parameters:

command - The command to dispatch

callback - The callback to notify with the processing result

sendAndWait

public <R> R sendAndWait(@Nonnull
 Object command)

Sends the given command and waits for its execution to complete, or until the waiting thread is interrupted.

Specified by:

sendAndWait in interface CommandGateway

Type Parameters:

R - The expected type of return value

Parameters:

command - The command to send

Returns:

The result of the command handler execution

Throws:

CommandExecutionException - when command execution threw a checked exception

sendAndWait

public <R> R sendAndWait(@Nonnull
 Object command,
 long timeout,
 @Nonnull
 TimeUnit unit)

Sends the given command and waits for its execution to complete, or until the given timeout has expired, or the waiting thread is interrupted.

When the timeout occurs, or the thread is interrupted, this method returns null.

Specified by:

sendAndWait in interface CommandGateway

Type Parameters:

R - The expected type of return value

Parameters:

command - The command to send

timeout - The maximum time to wait

unit - The time unit of the timeout argument

Returns:

The result of the command handler execution

Throws:

CommandExecutionException - when command execution threw a checked exception

send

public <R> CompletableFuture<R> send(@Nonnull
 Object command)

Description copied from interface: CommandGateway

Sends the given command and returns a CompletableFuture immediately, without waiting for the command to execute. The caller will therefore not receive any immediate feedback on the command's execution. Instead, hooks can be added to the returned CompletableFuture to react on success or failure of command execution. Note that this operation expects the CommandBus to use new threads for command execution.

The given command is wrapped as the payload of the CommandMessage that is eventually posted on the CommandBus, unless the command already implements Message. In that case, a CommandMessage is constructed from that message's payload and MetaData.

Specified by:

send in interface CommandGateway

Parameters:

command - The command to dispatch.

Returns:

A CompletableFuture which will be resolved successfully or exceptionally based on the eventual command execution result.

registerDispatchInterceptor

@Nonnull
public Registration registerDispatchInterceptor(@Nonnull
 MessageDispatchInterceptor<? super CommandMessage<?>> dispatchInterceptor)

Description copied from class: AbstractCommandGateway

Registers a command dispatch interceptor within a CommandGateway.

Specified by:

registerDispatchInterceptor in interface MessageDispatchInterceptorSupport<CommandMessage<?>>

Overrides:

registerDispatchInterceptor in class AbstractCommandGateway

Parameters:

dispatchInterceptor - To intercept command messages

Returns:

a registration which can be used to cancel the registration of given interceptor