org.axonframework.commandhandling.distributed

Enum UnresolvedRoutingKeyPolicy

java.lang.Object

java.lang.Enum<UnresolvedRoutingKeyPolicy>

org.axonframework.commandhandling.distributed.UnresolvedRoutingKeyPolicy

All Implemented Interfaces:

Serializable, Comparable<UnresolvedRoutingKeyPolicy>, RoutingStrategy

public enum UnresolvedRoutingKeyPolicy
extends Enum<UnresolvedRoutingKeyPolicy>
implements RoutingStrategy

Set of simple RoutingStrategy implementations. Could for example be used as fallback solutions when another RoutingStrategy is unable to resolve the routing key.

Since:

2.0

Author:

Allard Buijze

Enum Constant Summary

Enum Constants

Enum Constant and Description
ERROR A RoutingStrategy which always throws a CommandDispatchException regardless of the CommandMessage received.
RANDOM_KEY Policy that indicates a random key is to be returned when no Routing Key can be found for a Command Message.
STATIC_KEY Policy that indicates a fixed key ("unresolved") should be returned when no Routing Key can be found for a Command Message.

Method Summary

Modifier and Type	Method and Description
String	getRoutingKey(CommandMessage<?> command) Generates a routing key for the given command.
static UnresolvedRoutingKeyPolicy	valueOf(String name) Returns the enum constant of this type with the specified name.
static UnresolvedRoutingKeyPolicy[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

ERROR

public static final UnresolvedRoutingKeyPolicy ERROR

A RoutingStrategy which always throws a CommandDispatchException regardless of the CommandMessage received. Only feasible as a fallback solution which should straight out fail if the intended policy is unable to resolve a routing key.

Note that when the routing key is based on static content in the CommandMessage, the exception raised should extend from AxonNonTransientException to indicate that retries do not have a chance to succeed.

See Also:

RetryScheduler

RANDOM_KEY

public static final UnresolvedRoutingKeyPolicy RANDOM_KEY

Policy that indicates a random key is to be returned when no Routing Key can be found for a Command Message. This effectively means the Command Message is routed to a random segment.

Although not required to be fully random, implementations are required to return a different key for each incoming command. Multiple invocations for the same command message may return the same value, but are not required to do so.

STATIC_KEY

public static final UnresolvedRoutingKeyPolicy STATIC_KEY

Policy that indicates a fixed key ("unresolved") should be returned when no Routing Key can be found for a Command Message. This effectively means all Command Messages with unresolved routing keys are routed to a the same segment. The load of that segment may therefore not match the load factor.

Method Detail

values

public static UnresolvedRoutingKeyPolicy[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (UnresolvedRoutingKeyPolicy c : UnresolvedRoutingKeyPolicy.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static UnresolvedRoutingKeyPolicy valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

getRoutingKey

public String getRoutingKey(@Nonnull
                            CommandMessage<?> command)

Description copied from interface: RoutingStrategy

Generates a routing key for the given command. Commands that should be handled by the same segment, should result in the same routing key.

Specified by:

getRoutingKey in interface RoutingStrategy

Parameters:

command - the command to create a routing key for

Returns:

the routing key for the command