Migrate an Application/Library Project

This page is the entry point to learn how to migrate an Application or a Library project created with the SDK 5 or lower to the SDK 6. It covers the following items:

  • Build descriptor file

  • Configuration

  • Build scripts

Build Descriptor File

The module.ivy file of the SDK 5 project must be replaced by a build.gradle.kts file and a settings.gradle.kts file. The settings.gradle.kts contains the name of the project, whereas the build.gradle.kts file contains all the other information (module type, group, version, …).

The following chapters describe how to convert the sections of the module.ivy file to the SDK 6 format.

Build Type

The SDK 5 build type defined in the module.ivy file with the ea:build tag is replaced by a plugin in the build.gradle.kts file. For example, here is the block to add at the beginning of the file to migrate a build-microej-javalib SDK 5 module:

plugins {
    id("com.microej.gradle.addon-library") version "0.20.0"
}

The mapping between the main SDK 5 build types and Gradle plugins is:

MMM Build Type

Gradle Plugin

build-microej-javalib

com.microej.gradle.addon-library

build-application

com.microej.gradle.application

build-firmware-singleapp

com.microej.gradle.application

build-firmware-multiapp

com.microej.gradle.application

build-std-javalib

com.microej.gradle.jse-library

build-microej-mock

com.microej.gradle.mock

build-runtime-api

com.microej.gradle.runtime-environment

Module Information

The module information defined by the info tag in the module.ivy file are split in the 2 following descriptor files:

  • settings.gradle.kts

    • The property rootProject.name replaces the module attribute.

  • build.gradle.kts

    • The property group replaces the organisation attribute.

    • The property version replaces the revision attribute.

So for example, the following info tag:

<info organisation="com.mycompany" module="myProject" status="integration" revision="0.1.0">

will be converted to:

settings.gradle.kts
rootProject.name = "myProject"
build.gradle.kts
group = "com.mycompany"
version = "0.1.0"

Note

Refer to Manage Versioning section for more information on the way to define the module version.

Dependencies

The dependencies tag in the module.ivy file is replaced by the dependencies block in the build.gradle.kts file. Each dependency is tight to a Gradle configuration. For example, migrating a dependency used at compile time and runtime should use the implementation configuration, so the following dependency:

<dependency org="ej.api" name="edc" rev="1.3.5" />

will be converted to:

implementation("ej.api:edc:1.3.5")

wheras a dependency used for the tests only should use the testIplementation configuration, so the following dependency:

<dependency conf="test->*" org="ej.library.test" name="junit" rev="1.7.1"/>

will be converted to:

testImplementation("ej.library.test:junit:1.7.1")

Also note that this will not resolve snapshot builds since versions are explicit in SDK 6, see this chapter for more details. To resolve both snapshot and release versions, use [1.0.0-RC,1.0.0] instead of 1.0.0.

Note

If the dependency relates to another module of the same project, you may use a multi-project structure instead (see Multi-Project Build Basics).

Refer to the Add a Dependency page to go further on the Gradle dependencies and configurations.

Configuration Folder

The build folder located at the root of the project and containing the Application configuration properties is replaced by the configuration folder. This change is required since Gradle uses the build folder to store the generated files and artifacts (equivalent of the MMM target~ folder).

Specific Configuration

Some configuration options are available in SDK 6 in a different way than in SDK 5. This chapter goes through all this specific configuration options.

You can refer to the Module Natures page for a complete list of configurations.

Main class of Standalone Application

The main class of a Standalone Application is defined in SDK 5 with the property application.main.class in the module.ivy file:

<ea:property name="application.main.class" value="com.mycompany.Main"/>

It must now be defined in SDK 6 by the applicationEntryPoint property of the microej block in build.gradke.kts file:

microej {
   applicationEntryPoint = "com.mycompany.Main"
}

Feature Entry Point class of Sandboxed Application

The Feature Entry Point class of a Sandboxed Application is defined in SDK 5 with the property entryPoint in the *.kf file:

entryPoint=com.mycompany.MyFeature

It must now be defined in SDK 6 by the applicationEntryPoint property of the microej block in the build.gradke.kts file:

microej {
   applicationEntryPoint = "com.mycompany.MyFeature"
}

Tests Pattern

The pattern of the executed tests is defined in SDK 5 with the property test.run.includes.pattern:

<ea:property name="test.run.includes.pattern" value="**/_AllTests_MyTest.class"/>

It must now be defined in SDK 6 by the filter object of the test task in the build.gradke.kts file:

testing {
   suites {
     val test by getting(JvmTestSuite::class) {

         ...

         targets {
             all {
                 testTask.configure {
                     filter {
                         includeTestsMatching("MyTest")
                     }
                 }
             }
         }
     }
   }
}

Example

This section gives an example of a migration from a SDK 5 Application project to SDK 6. Here are the projects strucuture side by side:

SDK 5 Project

SDK 6 Project

|- src
|   |- main
|   |   |- java
|   |   |- resources
|   |- test
|       |- java
|       |- resources
|- build
|   |- common.properties
|- module.ivy
|- module.ant
|- src
|   |- main
|   |   |- java
|   |   |- resources
|   |- test
|       |- java
|       |- resources
|- configuration
|   |- common.properties
|- build.gradle.kts
|- settings.gradle.kts

And here the migration from a module.ivy file to a build.gradle.kts file and a settings.gradle.kts file:

SDK 5 and lower

module.ivy
<ivy-module version="2.0" xmlns:ea="http://www.easyant.org" xmlns:m="http://ant.apache.org/ivy/extra" xmlns:ej="https://developer.microej.com" ej:version="2.0.0">
   <info organisation="com.mycompany" module="myProject" status="integration" revision="0.1.0">
      <ea:build organisation="com.is2t.easyant.buildtypes" module="build-application" revision="9.2.+">
         <ea:property name="test.run.includes.pattern" value="**/_AllTests_*.class"/>
      </ea:build>
   </info>

   <configurations defaultconfmapping="default->default;provided->provided">
      <conf name="default" visibility="public" description="Runtime dependencies to other artifacts"/>
      <conf name="provided" visibility="public" description="Compile-time dependencies to APIs provided by the platform"/>
      <conf name="platform" visibility="private" description="Build-time dependency, specify the platform to use"/>
      <conf name="documentation" visibility="public" description="Documentation related to the artifact (javadoc, PDF)"/>
      <conf name="source" visibility="public" description="Source code"/>
      <conf name="dist" visibility="public" description="Contains extra files like README.md, licenses"/>
      <conf name="test" visibility="private" description="Dependencies for test execution. It is not required for normal use of the application, and is only available for the test compilation and execution phases."/>
      <conf name="microej.launch.standalone" visibility="private" description="Dependencies for standalone application. It is not required for normal use of the application, and is only available when launching the main entry point on a standalone MicroEJ launch."/>
   </configurations>

   <publications>
      <!-- keep this empty if no specific artifact to publish -->
      <!-- must be here in order to avoid all configurations for the default artifact -->
   </publications>

   <dependencies>
      <!--
         Put your custom Runtime Environment dependency here. For example:

         <dependency org="com.company" name="my-runtime-api" rev="1.0.0" conf="provided->runtimeapi" />
      -->
      <!--
         Or put direct dependencies to MicroEJ libraries if your Application is not intended to run on a specific custom Runtime Environment.
      -->
      <dependency org="ej.api" name="edc" rev="1.3.5" />
      <dependency org="ej.api" name="kf" rev="1.6.1" />

      <dependency conf="test->*" org="ej.library.test" name="junit" rev="1.7.1"/>

      <dependency org="com.microej.platform.esp32.esp-wrover-kit-v41" name="HDAHT" rev="1.8.0" conf="platform->default" transitive="false"/>
   </dependencies>
</ivy-module>

SDK 6

settings.gradle.kts
rootProject.name = "myProject"
build.gradle.kts
plugins {
    id("com.microej.gradle.application") version "0.20.0"
}

group = "com.mycompany"
version = "0.1.0"

dependencies {
   implementation("ej.api:edc:1.3.3")
   implementation("ej.api:kf:1.6.1")

   testImplementation("ej.library.test:junit:1.7.1")

   microejVee("com.microej.platform.esp32.esp-wrover-kit-v41:HDAHT:1.8.2")
}

Build Scripts

SDK 5 supports the use of the module.ant and override.module.ant to customize the build process. These files are not supported anymore with Gradle. Instead, since Gradle build files are code, customizations can be applied directly in the build files.

As an example, defining a property conditionnaly is done as follows in a module.ant file:

<target name="my-project:define-properties" extensionOf="compile">
   <condition property="myProperty" value="myValue">
      <not><equals arg1="${anotherProperty}" arg2="anotherValue"/></not>
   </condition>
</target>

and as follows in a build.gradle.kts file:

var myProperty = ""
tasks.register("defineProperties") {
   if(project.properties["anotherProperty"] == "anotherValue") {
      myProperty = "myValue"
   }
}

tasks.compileJava {
   dependsOn("defineProperties")
}