Modules
Axon Framework consists of a number of modules that provide specific capabilities. Depending on the exact needs of your project, you will need to include one or more of these modules.
There are currently two ways of obtaining the module binaries: either download the binaries from our website or preferably configure a repository for your build system (Maven, Gradle).
To not be bothered with version compatibility issues between framework and the extensions, it is recommended to use the BOM.
Axon modules are available on Maven Central.

Main modules

Axon 'Main Modules' are the modules that have been thoroughly tested and are robust enough to use in demanding production environments. The maven groupId of all these modules is org.axonframework. Visit Maven Central Repository to copy coordinates for the version you need.
Quick start an Axon Application
The Axon Spring Boot Starter module is the quickest start in to an Axon project as it will retrieve all the required modules/dependencies transitively. Alternatively, you can manually select individual modules for a customized configuration.
Module
Artifact Id
Group Id
Maven Central
axon-messaging
org.axonframework
available
axon-modelling
org.axonframework
available
axon-eventsourcing
org.axonframework
available
axon-configuration
org.axonframework
available
Axon Test
axon-test
org.axonframework
available
axon-server-connector
org.axonframework
available
axon-spring
org.axonframework
available
axon-spring-boot-starter
org.axonframework
available
axon-disruptor
org.axonframework
available
axon-metrics
org.axonframework
available
axon-micrometer
org.axonframework
available
axon-legacy
org.axonframework
available

Axon Messaging

This module contains all necessary components and building blocks to support command, event and query messaging.

Axon Modeling

This module contains the necessary components to create domain models, like Aggregates and Sagas.

Axon Event Sourcing

This module contains all necessary infrastructure components to support Event Sourcing, Command and Query Models.

Axon Test

This module contains test fixtures that you can use to test Axon based components, such as your Command Handlers, Aggregates and Sagas. You typically do not need this module at runtime and will only need to be added to the classpath for running tests.

Axon Configuration

This module contains all the necessary components to configure an Axon application.

Axon Server Connector

This module provides infrastructure components that connect to Axon Server.

Axon Spring

This module allows Axon Framework components to be configured in the Spring Application context. It also provides a number of building block implementations specific to Spring Framework, such as an adapter for publishing and retrieving Axon Events on a Spring Messaging Channel.

Axon Spring Boot Starter

This module provides Spring Boot auto-configuration for your project. It is by far the easiest option to get started as it automatically configures all Axon components. It is explained in more details here.

Axon Disruptor

This module contains a specific CommandBus and Command Handling solution based on the Disruptor paradigm.

Axon Metrics

This module provides basic implementations based on Coda Hale to collect the monitoring information.

Axon Micrometer

This module provides basic implementations based on Micrometer to collect the monitoring information. Micrometer is a dimensional-first metrics collection facade whose aim is to allow you to time, count, and gauge your code with a vendor neutral API.

Axon Legacy

This module contains components that enable migration of older Axon projects to use the latest Axon version.

Extension modules

Besides main modules, there are several extension modules which complement Axon Framework. They address distribution concerns of Axon Framework towards non-Axon Server solutions. The maven groupId of these extensions starts with org.axonframework.extensions.*. Visit Maven Central Repository to copy coordinates for the version you need.
Module
Artifact Id
Group Id
Maven Central
GitHub
Axon AMQP
axon-amqp
org.axonframework.extensions.amqp
available
available
axon-amqp-spring-boot-starter
org.axonframework.extensions.amqp
available
available
Axon CDI
axon-cdi
org.axonframework.extensions.cdi
available
available
axon-jgroups
org.axonframework.extensions.jgroups
available
available
axon-jgroups-spring-boot-starter
org.axonframework.extensions.jgroups
available
available
axon-kafka
org.axonframework.extensions.kafka
available
available
axon-kafka-spring-boot-starter
org.axonframework.extensions.kafka
available
available
axon-kotlin
org.axonframework.extensions.kotlin
available
available
axon-mongo
org.axonframework.extensions.mongo
available
available
axon-reactor
org.axonframework.extensions.reactor
available
available
axon-springcloud
org.axonframework.extensions.springcloud
available
available
axon-springcloud-spring-boot-starter
org.axonframework.extensions.springcloud
available
available
axon-tracing
org.axonframework.extensions.tracing
available
available
axon-tracing-spring-boot-starter
org.axonframework.extensions.tracing
available
available

Axon AMQP

This module provides components that allow you leverage an AMQP-based message broker as an Event Message distribution mechanism. This allows for guaranteed-delivery, even when the Event Handler node is temporarily unavailable.

Axon AMQP Spring Boot Starter

This module provides Spring auto-configuration on top of the axon-amqp module.

Axon CDI

This module provides support for Contexts and Dependency Injection (CDI) for the Java EE platform.

Axon JGroups

This module provides integration with JGroups for command distribution. JGroups should be regarded as a reliable messaging toolkit.

Axon JGroups Spring Boot Starter

This module provides Spring auto-configuration on top of the axon-jgroups module

Axon Kafka

This module provides integration with Kafka for event distribution. As such it plays a similar role as the Axon AMQP extension and thus is not a replacement Event Storage mechanism. Kafka is a distributed message streaming platform.

Axon Kafka Spring Boot Starter

This module provides Spring auto-configuration on top of the axon-kafka module.

Axon Kotlin

This module provides a set of reified operations, among others, to allow a cleaner Kotlin coding experience when using Axon.

Axon Reactor

This module provides integration with Project Reactor.

Axon Mongo

This module provides event and saga store implementations that store event streams and sagas in a MongoDB database. MongoDB is a document based NoSQL database.

Axon Spring Cloud

This module provides integration with Spring Cloud for command distribution. Spring Cloud provides an API for common distributed system patterns.

Axon Spring Cloud Spring Boot Starter

This module provides Spring auto-configuration on top of the axon-springcloud module

Axon Tracing

This module provides support for distributed tracing of Axon applications. The Open Tracing standard is used to provide the tracing capabilities.

Axon Tracing Spring Boot Starter

This module provides Spring auto-configuration on top of the axon-tracing module

Axon Bill of Materials

In addition to the main framework modules and the extensions, Axon also has a Bill of Materials, or BOM. The BOM is provided to ensure the use of compatible framework and extension dependencies inside an Axon application. As such, it is the recommended approach towards defining the overall Axon version used inside of an application.
Module
Artifact Id
Group Id
Maven Central
GitHub
Axon BOM
axon-bom
org.axonframework
available
available
For using the BOM, you would add the axon-bom dependency to your dependency management system:
Maven
Gradle
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...
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<dependencyManagement>
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<dependencies>
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<dependency>
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<groupId>org.axonframework</groupId>
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<artifactId>axon-bom</artifactId>
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<version>${version.axon}</version>
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<type>pom</type>
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<scope>import</scope>
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</dependency>
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12
...
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14
</dependencies>
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</dependencyManagement>
16
...
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For usage with Gradle Version 4.x and below, apply the dependency-management-plugin like so:
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buildscript {
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repositories {
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jcenter()
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}
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dependencies {
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classpath "io.spring.gradle:dependency-management-plugin:0.5.1.RELEASE"
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}
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}
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10
apply plugin: "io.spring.dependency-management"
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After this, import the Axon BOM:
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dependencyManagement {
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imports {
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mavenBom 'org.axonframework:axon-bom:<VERSION>'
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}
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}
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Beginning with Gradle version 5.0, you can also omit the dependency-management plugin and instead use the platform dependency dsl to import maven boms:
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implementation(platform("org.axonframework:axon-bom:<VERSION>"))
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After that is in place, you can add any of the mentioned dependencies from framework and the extensions without specifying versions. Furthermore, you will be guaranteed that the provided versions in the BOM are compatible with one another.
Last modified 7mo ago