Package org.acemq.amqp.api

Class Topology

java.lang.Object

org.acemq.amqp.api.Topology

public final class Topology
extends Object

A topology as data: what exchanges, queues and bindings should exist.

Declared rather than performed. Because it is a value, it can be printed, diffed, reviewed in a pull request and applied by something other than the application that needs it, which is the difference between a topology you can reason about and a sequence of declare calls scattered through start-up code.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	Topology.BindingSpec	A binding that should exist.
static final class	Topology.Builder	Builds a Topology.
static final class	Topology.ExchangeSpec	An exchange that should exist.
static final class	Topology.QueueSpec	A queue that should exist.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEAD_LETTER_EXCHANGE	The exchange a queue's dead letters are reached through.
static final String	DEAD_LETTER_EXCHANGE_ARGUMENT	Where the broker sends a message this queue rejects or lets expire.
static final String	DEAD_LETTER_ROUTING_KEY_ARGUMENT	What routing key it is sent under, which a direct exchange matches against its bindings.

Method Summary

Modifier and Type	Method	Description
List<Topology.BindingSpec>	bindings()
static Topology.Builder	define()
List<Topology.ExchangeSpec>	exchanges()
List<Topology.QueueSpec>	queues()
String	toString()

Methods inherited from class java.lang.Object

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

Field Details

DEAD_LETTER_EXCHANGE

public static final String DEAD_LETTER_EXCHANGE

The exchange a queue's dead letters are reached through.

One exchange for the whole broker rather than one per queue, bound on each dead-letter queue's own name. It is the arrangement the Go, .NET, Python and Ruby libraries produce, so a broker shared between them already has it.

See Also:

• Constant Field Values

DEAD_LETTER_EXCHANGE_ARGUMENT

public static final String DEAD_LETTER_EXCHANGE_ARGUMENT

Where the broker sends a message this queue rejects or lets expire.

See Also:

• Constant Field Values

DEAD_LETTER_ROUTING_KEY_ARGUMENT

public static final String DEAD_LETTER_ROUTING_KEY_ARGUMENT

What routing key it is sent under, which a direct exchange matches against its bindings.

See Also:

• Constant Field Values

Method Details

define

public static Topology.Builder define()

exchanges

public List<Topology.ExchangeSpec> exchanges()

queues

public List<Topology.QueueSpec> queues()

bindings

public List<Topology.BindingSpec> bindings()

toString

public String toString()

Overrides:

toString in class Object