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JavaFX with Gradle error module not found

I'm creating a sample demo application with JavaFX in IntelliJ, but I need to use a library called the JavaFaker library. I'm using Gradle as the build system, but every time I try to add the library, either as the implementation in the build.gradle file, or via IntelliJ project structure options, the module.java file says error: module not found. I've already tried adding it to modules but nothing changes.
module-info.java
module com.example.demo1 {
requires javafx.controls;
requires javafx.fxml;
requires javafaker;
opens com.example.demo1 to javafx.fxml;
exports com.example.demo1;
}
build.gradle
plugins {
id 'java'
id 'application'
id 'org.openjfx.javafxplugin' version '0.0.10'
id 'org.beryx.jlink' version '2.24.1'
}
group 'com.example'
version '1.0-SNAPSHOT'
repositories {
mavenCentral()
}
ext {
junitVersion = '5.8.2'
javaFakerVersion = '1.0.2'
}
sourceCompatibility = '17'
targetCompatibility = '17'
tasks.withType(JavaCompile) {
options.encoding = 'UTF-8'
}
application {
mainModule = 'com.example.demo1'
mainClass = 'com.example.demo1.HelloApplication'
}
javafx {
version = '17.0.1'
modules = ['javafx.controls', 'javafx.fxml']
}
dependencies {
implementation("com.github.javafaker:javafaker:${javaFakerVersion}")
testImplementation("org.junit.jupiter:junit-jupiter-api:${junitVersion}")
testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:${junitVersion}")
}
test {
useJUnitPlatform()
}
jlink {
imageZip = project.file("${buildDir}/distributions/app-${javafx.platform.classifier}.zip") as RegularFile
options = ['--strip-debug', '--compress', '2', '--no-header-files', '--no-man-pages']
launcher {
name = 'app'
}
}
jlinkZip {
group = 'distribution'
}
error message
> Task :HelloApplication.main() FAILED
Error occurred during initialization of boot layer
java.lang.module.FindException: Module javafaker not found, required by com.example.demo1

I tried for a while to get this to work with Gradle but was unable to. I don't know Gradle well, but unless you do, I don't advise trying it.
Alternate option: use a static import
I didn't try this, but this is suggested in another answer.
Before you try this, see:
What's the difference between requires and requires static in module declaration
It is IMO, a bit of a hack in this usage case. This makes the module optional at runtime. But, if the module is on the classpath instead of the module path its code can still be used. More information quoted from the linked answer:
A requires static clause expresses a dependency that is optional at
run time. That means at compile time the module system behaves exactly
as described above.
At run time, on the other hand, it mostly ignores requires static
clauses. If it encounters one, it does not resolve it. That means, if
an observable module is only referenced with requires static, it does
not make it into the module graph!
Alternate option: Non-modular project
You can fix this issue by making your project non-modular:
Delete your module-info.java file.
Run your application with JavaFX modules on the module-path.
The org.openjfx.javafxplugin you are already doing will help achieve this by specifying the modules to be used.
To execute the application directly in the IDE rather than through Gradle, you will need to specify the module options to the VM for the IDE execution configuration (information on that is in the getting started documentation at openjfx.io).
For packaging, switch to using the badass-runtime-plugin rather than the badass-jlink-plugin. This will package the application via jpackage rather than jlink (which cannot package non-modular applications or applications with automatic modules).
In the application block of your build file, you no longer need to specify the module for your application as you no longer have one.
While that means that your application is no longer modular, in this case, in my opinion, this is not such a big loss. The dependencies you are using are not well-defined modules, so you can't use jlink to create a package for your application, and you don't have the level of modular encapsulation and definition you would normally receive for fully modular projects.
For more information, see the Getting started instructions at:
https://openjfx.io/openjfx-docs/
Under the sections "Non-Modular with Gradle" for your selected IDE.
Alternate option: Using Maven
It is easy to get this to work with Maven.
Create a new JavaFX project
Choose Maven as your build system instead of Gradle.
Add the javafaker dependency to your pom.xml.
<dependency>
<groupId>com.github.javafaker</groupId>
<artifactId>javafaker</artifactId>
<version>1.0.2</version>
</dependency>
Press the refresh icon in the Maven window to reimport the Maven project into the IDE.
Add the requires clause for the javafaker module into your module-info.java
requires javafaker;
Add the code to use javafaker to your app.
I don't have code to use javafaker, so I could not verify that the last step would work, but, give it a try . . .
Why you can receive this issue when using Gradle, but not Maven
Looking at the Gradle Documentation section "Using libraries that are not modules":
A third case are traditional libraries that provide no module information at all — for example commons-cli:commons-cli:1.4. Gradle puts such libraries on the classpath instead of the module path. The classpath is then treated as one module (the so called unnamed module) by Java.
This is the case with the javafaker dependency that you are using. It has no module-info.java and does not define the property Automatic-Module-Name in its manifest file (which are the other two cases in the section). Both the other cases result in Gradle putting the library on the module path, but the case you have means that it is on the class path.
This is a problem when you want to access the code from a named module that you define, which you have because you created a module-info.java.
Your module can only find code and resources of modules it requires (which need to be on the module path), so you add requires javafaker to the module-info.java, and get the following when you try to run through the IDE:
java.lang.module.FindException: Module javafaker not found, required by com.example.demo1
So you remove the requires javafaker from the module-info.java as advised by the Gradle documentation I linked and you get the following when you try to compile:
Package 'com.github.javafaker' is declared in module 'javafaker', but module 'com.example.demo1' does not read it
So you must place the library in the module-info to use it, but you can't place the library in module-info because Gradle puts in on the classpath -> catch-22.
There are workarounds to this such as providing VM arguments to allow access to the unnamed module (which is the classpath), or maybe modifying the module path handling of the Gradle build and/or IDE somehow (I don't know how), but they are pretty ugly.
On the other hand, for this case, Maven acts differently from Gradle, it places the dependent library on the module path, even if it does not have a module-info.java or Automatic-Module-Name defined. This means that it was (for me) much easier to set up and use.
Incidental advice on module naming
This is not an error, but note: Although module names with numbers in them are now allowed due to a change in the module system specification, it is probably best not to put numbers in module names to prevent the module name and version info being confused.

I've had a similar issue recently. Adding static to the requires statement helped however. Maybe this will fix your issue without having to switch to maven.
So you'd need to add: requires static javafaker;

gradle-clover-plugin to get code coverage from separate module

I was tasked with splitting up a spring boot application to have multiple modules to look something like this:
root
app
build.gradle
rest
build.gradle
service
build.gradle
dao
build.gradle
model
build.gradle
build.gradle
settings.gradle
Note: there is no code folder in the root of the project. Each module has its own src root
Before splitting the code into modules, the gradle-clover-plugin was showing that we had 95% code coverage, but due to the way that the tests are now organized, the plugin is not able to see that some of the code is being tested in other modules
For instance some of the service Class methods are being tested from the rest module while testing the controllers.
Looking thru the documentation for the plugin (https://github.com/bmuschko/gradle-clover-plugin/blob/master/README.md), they mention specifying additionalSourceSets and additionalTestSourceSets in the example towards the bottom of the page, but it's not clear to me how to use those in my project
I added the following block from the example to my root build.gradle:
additionalSourceSet {
srcDirs = sourceSets.generatedCode.java.srcDirs
classesDir = sourceSets.generatedCode.java.outputDir
}
additionalTestSourceSet {
srcDirs = sourceSets.integrationTest.java.srcDirs
classesDir = sourceSets.integrationTest.java.outputDir
}
but was getting the following exception: Could not get unknown property 'generatedCode' for SourceSet container of type org.gradle.api.internal.tasks.DefaultSourceSetContainer.
I then tried swapping out generatedCode and integrationTest with the names of my modules in the root build.gradle but was getting the same exception
Finally I tried specifying those properties in the build.gradle for the module, but was getting the following exception: Could not find method additionalSourceSets() for arguments on object of type com.bmuschko.gradle.clover.CloverPluginConvention
Is it indeed possible to specify another modules' sources for the plugin to consider when generating the code coverage report for a different module?

Android studio 3.1 not recognizing jar annotation processing

I'm trying to implement my own annotation processor in my android studio project. All is working well and compiling until I add this simple line to build.gradle dependencies block:
dependencies {
.
.
.
annotationProcessor(':processor')
}
At that point I get this error when compiling:
Could not find :processor:. Required by:
project :app Search in build.gradle files
I've followed endless tutorials and nothing seems to help. I've just recently upgraded to AS 3.1 and thinking maybe it relates?
Here is the project structure: (mind you - here I add the annotation processor as a jar file. I've also attached an image trying to do it as a different module and same result)
Here is a different I'm trying to add it - creating the annotation processor in the same project with a different module and still no go:
Some extra info in pics...
Project structure:
app.build:
processor.build:
annotation:
MainActivity:
Processor implementation:

If you have everything inside the same artifact, — annotation processor, it's annotations and library classes, used by processor users, Android Gradle plugin requires you to declare two dependencies on the same artifact:
annotationProcessor project(':processor')
compile project(':processor')
or
annotationProcessor files('libs/processor.jar')
compile files('libs/processor.jar')
Note, that such setup might become unsupported in future. It is advisable to split your processor in separate module and make it depend on the rest of code. After doing so you will be able to declare dependencies like this:
annotationProcessor project(':processor') // processor-only jar
compile project(':processor-api') // annotations and classes for user code

Gradle: What is the difference between classpath and compile dependencies?

When adding dependencies to my project I am never sure what prefix I should give them, e.g. "classpath" or "compile".
For example, should my dependencies below be compile time or classpath?
Also, should this be in my applications build.gradle or in the module specific build.gradle?
Current build.gradle (at application level):
apply plugin: 'java'
repositories {
mavenCentral()
}
dependencies {
compile 'org.hibernate:hibernate-core:5.0.5.Final'
compile 'mysql:mysql-connector-java:5.1.38'
}

If buildscript itself needs something to run, use classpath.
If your project needs something to run, use compile.
The buildscript{} block is for the build.gradle itself.
For multi-project building, the top-level build file is for the root project, the specific build file is for sub-project (module).
Top-level build file where you can add configuration options common to all sub-projects/modules.
Do not place your application dependencies in top-level build file, they belong in the individual module build.gradle files

I'm going to guess that you're referencing compile and classpath within the dependencies {} block. If that is so, those are dependency Configurations.
A configuration is simply a named set of dependencies.
The compile configuration is created by the Java plugin. The classpath configuration is commonly seen in the buildScript {} block where one needs to declare dependencies for the build.gradle, itself (for plugins, perhaps).

If I understand correctly, you're confusing Project.dependencies script block with the Project.buildscript.dependencies script block (just like I did when I reached this question).
I'll try to answer this with what I found.
I think you should be already familiar with the Project.dependencies script block. In this block, we declare dependencies that are required by our source code. There are several ways to declare a dependency that we need for the project. See Gradle Tutorial: Dependency Types. I'll only mention the part that is the most relevant to this problem:
compile 'org.hibernate:hibernate-core:5.0.5.Final' is a module dependency declaration. The compile configuration (which is now deprecated by the implementation configuration.) is merely a keyword for Implementation only dependencies. It is not a keyword describing which type of dependency it is (by type here I'm following the three types defined in the tutorial, i.e. module, file, and project.)
In Gradle Tutorial: Organizing Build Logic it says:
If your build script needs to use external libraries, you can add them
to the script’s classpath in the build script itself. You do this
using the buildscript() method, passing in a closure which declares
the build script classpath.
This is the same way you declare, for example, the Java compilation
classpath. You can use any of the dependency types described in
Dependency Types, except project dependencies.
Having declared the build script classpath, you can use the classes in
your build script as you would any other classes on the classpath.
I hope things are getting clear to you now.
With classpath "com.android.tools.build:gradle:${Versions.android_gradle_plugin}" we're setting classpath method with com.android.tools.build:gradle:${Versions.android_gradle_plugin} which is a module dependency that is used by the build script itself rather than the source in your project.
On the other hand, with compile 'org.hibernate:hibernate-core:5.0.5.Final' we're declaring a module dependency required for your project with the compile configuration.
tl;dr: The classpath, compile, and implementation are all keywords that can be used against dependencies under different circumstances. The former is used when you want to pass in a dependency to the build script, and the latter is one of the configuration you may want to declare.

Android:
classpath in project build.gradle —— the implementation after classpath is only used by gradle it self, used in build script. So if i add the implementation (such as retrofit) in the project build.gradle classpath 'retrofit...', i can't get retrofit in my code!! Because —— my code can't see it, only the buildscript can see it.
implementation in app build.gradle —— add the implementation your code can use!!

How to allow user to change the version of the library which is used by a plugin in Gradle?

In my plugin I call static bootstrapping method MutationCoverageReport.main(arg) from a library which is a compile dependency of my plugin. I would like to allow a plugin user to change the version of the library which should be used (assuming the selected version has compatible API).
I could advice user to exclude a transitive dependency from my plugin and add a dependency to the library in the requested version manually to buildscript.dependencies.classpath in his build.gradle, but this is not very elegant:
buildscript {
(...)
dependencies {
classpath('info.solidsoft.gradle.pitest:gradle-pitest-plugin:0.32.0') {
exclude(group: 'org.pitest')
}
classpath 'org.pitest:pitest-command-line:0.33'
}
}
I would like to be able to use libVersion parameter in my configuration closure, but I have some problems with two solutions I tried.
1. I could need to remove transitive dependencies from my plugin (an original library version and its dependencies) and add a library in requested version (from configuration closure) as a buildscript dependency.
In afterEvaluate it is to late (configurations are resolved) and I had problem to successfully hook with beforeEvaluate (is it triggered for single module project?).
2. I could change a classpath which is used to execute a static method from a library.
To do that I could create a custom class loader which would use my library classes (in requested version) before delegating to the parent class loader. I also would have to replace one liner with MutationCoverageReport.main(arg) with the reflection call using the new class loader.
Maybe there is a simpler way to modify a classpath by a plugin with which the mentioned method will be called?
Main questions. What would be the best way to allow plugin users to define the version of the library the plugin executes?

I'm not sure this is what you're looking for, but here's how the Jacoco plugin allows the user to configure the library being used.
JacocoPluginExtension
class JacocoPluginExtension {
// ...
String toolVersion = '0.32.0'
// ...
}
JacocoPlugin
class JacocoPlugin implements Plugin<Project> {
// ...
config.dependencies.add(this.project.dependencies.create("org.jacoco:org.jacoco.ant:${extension.toolVersion}"))
// ...
}

In another question about executing Java class with a separate classpath Peter Niederwieser provided 3 approaches. In the end modify my task to extend JavaExec. I set explicit set execution classpath which is separate from plugin execution classpath and can contain different library version.
The drawback is allows only to run main method, but it wasn't a problem in my case.