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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;

How can I stop Gradle deleting .jars from my project's module path?

I'm trying to develop a Gradle project which involves JavaFX.
Specs: Linux Mint 18.3, Java 11, Eclipse 2019-06, JavaFX: either 13 or 11...
A couple of useful answers to questions have helped me over the past hours: this one tells me (with useful clonable example) how to configure things, at least using a Java file to hold my project's main class (in fact I ultimately want to write all my code in Groovy ideally), in order to overcome the error "JavaFX runtime components are missing, and are required to run this application".
But Eclipse doesn't like it when you add the final step: the file module-info.java. At this point I have to confess I know nothing whatsoever about Eclipse "modules": only that this unknown aspect of the IDE has occasionally caused me frustrating headaches in the past. Probably time to read up on it now.
I should also clarify that at this point the Gradle tasks build and installdist (or assemble) work fine at the CLI. I am only concerned about getting rid of these horrid Eclipse white-cross-in-red-box error marks:
in module-info.java: "javafx.controls cannot be resolved to a module"
in Main.java: all the JavaFX classes have this next to them "Application [etc.] cannot be resolved to a type", and all the imports have "The type javafx.scene.Scene [etc.] is not accessible"
This answer says to download the JavaFX-JDK and then add various .jars from it to your project's module path. I did that: the horrid errors all disappeared!
Next time I did a Gradle - Refresh they all came back. I checked module path: all these .jar files had been removed. How can I stop the Gradle-Eclipse functionality messing with my configured module path?
edit
re the comment by Slaw: yes, already using
id 'org.openjfx.javafxplugin' version '0.0.8'
... my build.gradle javafx block looks like this:
javafx {
version = "13"
modules = [ 'javafx.controls', 'javafx.fxml' ]
}
(NB I have now tried experimenting by adding 'javafx.graphics' and 'javafx.base' to the above.)
The issue is that Gradle - Refresh nevertheless causes the above "disappearing .jars" phenomenon.
I tried adding this to my plugins block:
id 'org.javamodularity.moduleplugin' version '1.6.0' apply true/false // NB tried both
... no go: Gradle - Refresh leads to an incomprehensible (to me) error:
An exception occurred applying plugin request [id: 'org.openjfx.javafxplugin', version: '0.0.8']
> Failed to apply plugin [id 'org.openjfx.javafxplugin']
> Could not create task ':configJavafxRun'.
> Could not create task of type 'ExecTask'.
> Could not generate a decorated class for class org.openjfx.gradle.tasks.ExecTask.
> org/javamodularity/moduleplugin/tasks/ModuleOptions

How to change the working directory using JavaFX with Gradle?

The title says all. How do I change the working/runtime directory when using JavaFX with Gradle in Eclipse?
Basically, I have a project that requires log4j and initiates a basic logger which uses the "logs/" directory from the place the jar is run. This directory is being made in the home of the source, but I want it to be made in the "run/" directory. I'm assuming for other files that will be created, they will also have this same issue.
My build.gradle is this:
// Plugins
plugins {
id 'application'
id 'org.openjfx.javafxplugin' version '0.0.7'
}
// Repositories
repositories {
jcenter()
mavenCentral()
}
// Dependencies
dependencies {
implementation 'com.google.code.gson:gson:2.8.5'
implementation 'org.apache.logging.log4j:log4j-core:2.12.0'
}
// JavaFX
javafx {
version = '12'
modules = ['javafx.controls']
}
mainClassName = 'net.protolauncher.backtest2.ProtoLauncher'
I am using Eclipse to run it, but this issue also occurs when just running the run task. I tried changing the Working Directory in the "Gradle Project" run configuration, but it didn't work at all (it just loaded forever).
To give an example, here's the directory of my source code: DirectoryX. Now, I made a folder in here called "run", like so: DirectoryX/run. When I run the program, I want my logs to go into DirectoryX/run/logs and similar files to go into the run directory. However, when running with Gradle my log files are being created in DirectoryX/logs.
This probably made no sense, but if it did, I really appreciate any help I can get.

After hours of searching online to no avail, I finally found a StackOverflow answer that solves the question. Turns out, JavaExec is a complicated thing, and what I was doing was specific to that, NOT JavaFx.

In Buildship: how can I substitute a Gradle project with a built jar?

I would like to be a able to get Eclipse to ignore one Gradle project, and instead use a pre-built version of it.
Background
I have a project "parser" written in Scala, and a dozen others written in Java. The weakest link in my tool-set is Scala IDE. I use this plugin to edit & compile Scala code, but unfortunately it breaks the Java (JDT) tooling quite badly in mixed-language projects*.
Specifically: Call-hierarchy is missing results, searches crash and so on. Also Scala IDE appears to have lost funding and the issues sound fairly fundamental, so I'm not holding my breath for these issues to be fixed.
With Maven (m2e) I had a workaround I was quite happy with:
Build as a .jar put into my local .m2 repository:
cd parser; mvn install
In Eclipse, close the "parser" project
"Like magic", m2e simply picked up the most recent 'installed' .jar and used it in place of the closed project.
An awesome answer would be how to get Gradle to do that!
However all I wish for is any solution that meets these...
Requirements
That I can open Project parser when necessary (which is seldom),
to edit and build changes via the Gradle command-line.
I will close it when done.
Other projects use the built .jar from my local .m2 repo.
(It's fine if they always do so.)
The change must not affect others who don't use Eclipse
(ideally) the change can be used by other Eclipse users
Approaches
A similar question had this good answer by #lance-java with a number of general suggestions. I think I can rule out these ideas:
composite build support / multiple repos. Other team members wouldn't think it makes sense to build this project separately, as it is quite closely integrated with the others.
dependency substitution rules - doesn't appear to meet requirement 3.
Something along the lines of lance-java's idea #4 sounds viable. Paraphrasing...
"use the eclipse plugin [in conjunction with] Buildship, e.g. using the whenMerged hook to tweak the generated .classpath [of all the Java projects]."
UPDATE: [18 Apr]: I had hit a brick wall in this approach. Buildship was not putting the built .jar onto the runtime classpath. (UPDATE 2: Now resolved - see my answer.)
Questions
The main question: How can I structure a solution to this, that will actually work & avoid any major pitfalls?
Note that the project itself has a few dependencies, specifically:
dependencies {
compile 'org.scala-lang:scala-library:2.12.4'
compileOnly 'com.google.code.findbugs:jsr305:1.3.9'
antlr 'org.antlr:antlr4:4.5.3'
}
So a sub-question may be: How to pull these in into the other projects without duplicating the definition? (If that doesn't work automatically.)

So the solution was a bit involved. After adding 'maven-publish' to create the library, I then implemented the following to force Eclipse to use the prebuilt library:
subprojects {
// Additional configuration to manipulate the Eclipse classpaths
configurations {
parserSubstitution
}
dependencies {
parserSubstitution module("com.example:parser:${project.version}")
}
apply plugin: 'eclipse'
eclipse {
classpath {
plusConfigurations += [ configurations.pseLangSubstitution ]
file {
whenMerged { cp ->
// Get Gradle to add the depedency upon
// parser-xxx.jar via 'plusConfigurations' above.
// Then this here if we have a dependency on Project(':parser')
// - If so, remove it (completing the project -> jar substitution).
// - If not, remove the .jar dependency: it wasn't needed.
def usesParser = entries.removeAll {
it instanceof ProjectDependency && it.path.startsWith('/parser')
}
def parserJar =
cp.entries.find { it instanceof Library && it.path.contains('parser-') }
if (usesParser) {
// This trick stops Buildship deleting it from the runtime classpath
parserJar ?. entryAttributes ?. remove("gradle_used_by_scope")
} else {
cp.entries.remove { parserJar }
}
}
}
}
So there are 2 parts to this:
Using 'plusConfigurations' felt a bit round-about. I ended up doing this because I could not see how to construct class Library classpath entries directly. However it could well be that this is required to implement the 'transient dependencies' correctly anyway. (See the end of the question.)
The trick to stop Buildship removing the .jar from the runtime classpath (thus deviating from a Gradle command-line launch) was provided to me by a Gradle developer in this discussion.
Usage
The solution works just as I hoped. Every time some code in this library is modified, I execute the following task of mine on the command line (which also does some other code & resource generation steps, in addition to building the parser jar):
./gradlew generateEclipse
Then in Eclipse I press keyboard shortcuts for "Gradle -> Refresh Gradle Projects", Build.
And harmony is restored. :-)
Navigating to the (prebuilt) source of parser works.
If I need to edit the source, I can open the parser project and edit it. Scala-IDE still does a good job for this.
When I'm done I execute the command, close the project and my Java tools are happy.

In parser project
You shoud use the maven-publish plugin with the publishToMavenLocal task
apply plugin: 'maven-publish'
group = 'your.company'
version = '1.0.0'
publishing {
publications {
mavenJava(MavenPublication) {
from components.java
pom.withXml {
def root = asNode()
root.appendNode('name', 'Your parser project name')
root.appendNode('description', 'Your parser project description')
}
}
}
}
Everytime you make a modification, just change the version number if necessary and go with gradle publishToMavenLocal
In other java project using parser
Just use parser as a regular dependency :
repositories {
mavenLocal()
...
}
compile 'your.company:parser:1.0.0'
If my understanding of your situation is good, it should do the trick.

Using jackson-dataformat-xml on android

I'm strugling with using jackson-dataformat-xml on android
I have some very basic code that works fine on oracle jre
JacksonXmlModule module = new JacksonXmlModule();
module.setDefaultUseWrapper(false);
XmlMapper xmlMapper = new XmlMapper(module);
First I tried official documentation adapted for gradle (by me, not sure if done correctly):
compile 'com.fasterxml.jackson.core:jackson-core:2.5.4'
compile 'com.fasterxml.jackson.core:jackson-annotations:2.5.4'
compile 'com.fasterxml.jackson.core:jackson-databind:2.5.4'
compile 'com.fasterxml.jackson.dataformat:jackson-dataformat-xml:2.5.4'
compile 'org.codehaus.woodstox:woodstox-core-asl:4.4.1'
compile 'javax.xml.stream:stax-api:1.0-2'
Result: gradle fails build time about bundling corelibraries into an application
...
:app:preDexDebug
trouble processing "javax/xml/stream/EventFilter.class":
Ill-advised or mistaken usage of a core class (java.* or javax.*)
when not building a core library.
...
2nd attempt trying to follow Sean's answer
(Basicly he repackages corelibs with prefix names and rebuilds jackson-dataformat-xml to use the prefixed names)
compile 'com.fasterxml.jackson.core:jackson-core:2.1.2'
compile 'com.fasterxml.jackson.core:jackson-annotations:2.1.2'
compile 'com.fasterxml.jackson.core:jackson-databind:2.1.2'
// Repackaged XML-specific libraries
compile 'edu.usf.cutr.android.xml:jackson-dataformat-xml-android:2.1.2'
compile 'edu.usf.cutr.android.xml:stax2-api-android:3.1.1'
compile 'edu.usf.cutr.android.xml:stax-api-android:1.0-2'
compile 'edu.usf.cutr.android.xml:aalto-xml-android:0.9.8'
And build time failed on duplicates
Duplicate files copied in APK META-INF/services/com.fasterxml.jackson.core.ObjectCodec
so added:
packagingOptions {
...
exclude 'META-INF/services/com.fasterxml.jackson.core.JsonFactory'
exclude 'META-INF/services/com.fasterxml.jackson.core.ObjectCodec'
}
When adding the exclusions it builds and deploys, but fails runtime on below stackdump (AFAIK it cant find the SAX provider, even tho it is added to the classpath to my understanding)
edu.usf.cutr.javax.xml.stream.FactoryConfigurationError: Provider com.bea.xml.stream.MXParserFactory not found
at edu.usf.cutr.javax.xml.stream.FactoryFinder.newInstance(FactoryFinder.java:72)
at edu.usf.cutr.javax.xml.stream.FactoryFinder.find(FactoryFinder.java:176)
at edu.usf.cutr.javax.xml.stream.FactoryFinder.find(FactoryFinder.java:92)
at edu.usf.cutr.javax.xml.stream.XMLInputFactory.newInstance(XMLInputFactory.java:136)
at com.fasterxml.jackson.dataformat.xml.XmlFactory.<init>(XmlFactory.java:97)
at com.fasterxml.jackson.dataformat.xml.XmlFactory.<init>(XmlFactory.java:85)
at com.fasterxml.jackson.dataformat.xml.XmlFactory.<init>(XmlFactory.java:82)
at com.fasterxml.jackson.dataformat.xml.XmlMapper.<init>(XmlMapper.java:46)
What is the proper way to move forward on either #1 or #2?

Number 2 is the correct approach (Android doesn't like it when you include classes in the official Java package namespace - but then again, I wrote the original answer so I'm biased ;) ).
I believe the FactoryConfigurationError: Provider com.bea.xml.stream.MXParserFactory not found error is due to a bug in the Android build tools. In previous versions of ADT for Eclipse and Gradle plugin < 0.7.0 the /META-INF/* files are stripped from the JARs during the build process. It seems like >= v0.7.0 shouldn't have the problem according to Google, but from others' reports it sounds like it still may be problematic, and could potentially remove the META-INF/services/javax.xml.stream.XMLInputFactory file, which is required for the platform to register Aalto.
Try the workaround mentioned in AOSP issue 59658 comment 22:
right click on /src/main (where you have /java and /res folders),
select New > Folder > Java Resources Folder,
click Finish (do not change Folder Location),
right click on new /resources folder,
select New > Directory
enter "META-INF" (without quotes),
right click on /resources/META-INF folder,
select New > Directory
enter "services" (without quotes)
copy any file you need into /resources/META-INF/services
For you, in step 10 above you'd need to copy this file into /resources/META-INF/services. In case the file link is broken in the future, the name of the file is javax.xml.stream.XMLInputFactory and it consists of a single line:
com.fasterxml.aalto.stax.InputFactoryImpl
EDIT
If you get a "Error:duplicate files during packaging of APK... Path in archive: META-INF/services/javax.xml.stream.XMLInputFactory", you can try telling Gradle to keep the first occurrence with:
android {
packagingOptions {
pickFirst 'META-INF/services/javax.xml.stream.XMLInputFactory'
}
}
EDIT 2
This bug may be affecting "pickFirst". Please make sure you're running the latest version of Android Studio, and update your local tools and Android Gradle plugin to make sure you're running the most recent version of the tools. This may be fixed in Android Studio 1.3 RC1.

I have attempted to add XmlPull support to jackson xml. Find the forked project here:
https://github.com/finvu/jackson-dataformat-xml
Currently, only supported for version 2.9.6. (clone the branch jackson-dataformat-xml-2.9.6-XmlPull)
Sorry, I am not able to provide detailed documentation due to time constraints. If you have knowledge of git and maven to pull a specific branch and build the jar, then it should be relatively easy.

To those who will be in need of this in the future:
first integrate Jitpack in Your Android app, following their instructions:
https://jitpack.io/
Then paste teh GitHub url of jackson-dataformat-xml on Jitpack sites' corresponding text box. GitHub url is:
https://github.com/FasterXML/jackson-dataformat-xml.
That's it! Enjoy the result. :)