Overview

Application
Module

In this chapter, we’ll see about the application & module structures.

Application

An application is nothing but a configuration of a set of modules. The modules are built-time packages handled with Gradle build system.

Here is a directory structure of a typical axelor application:

Directory Structure

axelor-demo
└── src
│   └── main
│       ├── java
│       └── resources
│           └── META-INF
│               ├── axelor-config.properties (1)
│               └── persistence.xml (2)
├── gradle (3)
│   └── wrapper
│       ├── gradle-wrapper.jar
│       └── gradle-wrapper.properties
├── modules (4)
├── gradlew (5)
├── gradlew.bat (5)
├── settings.gradle (6)
└── build.gradle (7)

1	The application config file
2	The minimal persistence xml file to confirm JPA requirement
3	The directory to keep gradle wrapper files
4	The directory to keep module projects
5	The shell and batch scripts to execute the build with wrapper
6	The gradle settings script
7	The gradle build script

The modules directory contains application specific feature modules. First, let’s see about some important files here before checking module structure.

The build.gradle file is a build script used by gradle to build the application.

build.gradle

plugins {
  id 'com.axelor.app' (1)
}

axelor { (2)
  title = 'Axelor DEMO'
}

allprojects {

  group = 'com.axelor'
  version = '1.0.0'

  java {
    toolchain {
      languageVersion = JavaLanguageVersion.of(11) (3)
    }
  }

  afterEvaluate {
    test {
      useJUnitPlatform() (4)
      beforeTest { descriptor ->
        logger.lifecycle('Running: ' + descriptor)
      }
    }
  }
}

dependencies {
  // add dependencies
  implementation project(':axelor-contact') (5)
}

1	Use axelor application plugin
2	The application project config
3	Use Java 11
4	Use JUnit5 for unit testing
5	Add dependencies

The com.axelor.app gradle plugin defines an extension point axelor where we can define various properties.

title - display title for the application

Another important build script is the settings.gradle where we configure the gradle build and aggregates all the feature module projects to be used in current build process:

settings.gradle

pluginManagement {
  repositories {
    maven {
      url 'https://repository.axelor.com/nexus/repository/maven-public/' (1)
    }
  }
  plugins {
    id 'com.axelor.app' version '6.0.+' (2)
  }
}

dependencyResolutionManagement {
  repositories {
    mavenCentral() {
      content {
        excludeGroup 'com.axelor' (3)
      }
    }
    maven {
      url 'https://repository.axelor.com/nexus/repository/maven-public/'
    }
  }
}

rootProject.name = 'axelor-demo'

// Include modules
include 'modules:axelor-contact'

1	The axelor maven repository
2	The axelor app gradle plugin version
3	Use maven central but don’t load `com.axelor` from it

The include 'modules:axelor-contact' line tells gradle to include the module axelor-contact in current build cycle. It is required to list all the modules used by the application in settings.gradle file.

Module

The application project generally doesn’t provide any implementation logic. The functionalities should be provided by creating modules.

A module is again a gradle sub project. Usually created inside modules directory. However, you can use any directory structure. See gradle multi-project builds documentation for more details.

Now let’s see what a feature module directory structure looks like:

Directory Structure

axelor-contact
├── build.gradle (1)
└── src
    ├── main (2)
    │   ├── java
    │   └── resources
    │       ├── domains (3)
    │       ├── views (4)
    │       └── i18n (5)
    └── test (6)
        ├── java
        └── resources

1	The gradle build script
2	The main sources
3	The XML resources for domain object definitions
4	The XML resources for object view definitions
5	The CSV files with translations
6	The unit test sources

You can see the module structure follows standard maven/gradle directory structure.

Let’s see the build.gradle script for the module.

modules/axelor-contact/build.gradle

plugins {
  id 'com.axelor.app' (1)
}

axelor { (2)
  title = "Axelor :: Contact"
}

1	The gradle plugin for module project
2	The module project configuration

The com.axelor.app plugin defines an extension point axelor where we define various properties.

title - display title for the module
description - a short description about the module