Develop Reference

Why am I getting "java.lang.NoClassDefFoundError" despite referencing the library in eclipse and specifying the dependency in build.gradle?

The error gets thrown for org/apache/commons/compress/archivers/tar/TarArchiveInputStream as seen here.
I have referenced this library in eclipse (as seen here)
The dependency has also been specified in build.gradle. The contents of the gradle file:
plugins {
id 'org.spongepowered.plugin' version '0.9.0'
}
group = pluginGroup
version = pluginVersion
sourceCompatibility = '1.8'
targetCompatibility = '1.8'
dependencies {
compileOnly 'org.spongepowered:spongeapi:7.2.0'
annotationProcessor 'org.spongepowered:spongeapi:7.2.0'
compile 'org.apache.commons:commons-compress:1.21'
}
sponge.plugin.id = pluginId
Eclipse also does not flag any errors. Lines of code such as tarInput.getNextTarEntry() appear in the correct colour with no red underlining, and eclipse even autocompletes the names of methods found in commons-compress.
Given eclipse seems to be working correctly with the dependency, and given that running ./gradlew build leads to a successful build, I am therefore at a loss for why I am getting the java.lang.NoClassDefFoundError error.

#nitind helped. I focused upon runtime and found the problem was to do with my build.gradle file (even though the build was successful!). I changed it to this and the error has vanished:
buildscript {
repositories {
mavenCentral()
}
}
plugins {
id 'org.spongepowered.plugin' version '0.9.0'
}
apply plugin: 'java'
group = pluginGroup
version = pluginVersion
sourceCompatibility = '1.8'
targetCompatibility = '1.8'
dependencies {
compileOnly 'org.spongepowered:spongeapi:7.2.0'
annotationProcessor 'org.spongepowered:spongeapi:7.2.0'
compile 'org.apache.commons:commons-compress:1.21'
}
jar {
from configurations.compile.collect { zipTree it }
}
sponge.plugin.id = pluginId

Build and deploy JavaFX Applicationn with jlink

I have a script build.gradle, which created the IDEA development environment when creating a JavaFX project with Gradle support:
plugins {
id 'java'
id 'application'
id 'org.openjfx.javafxplugin' version '0.0.10'
id 'org.beryx.jlink' version '2.24.4'
id 'org.javamodularity.moduleplugin' version '1.8.10' apply false
}
group 'com.prototype'
version '1.0'
repositories {
mavenCentral()
}
ext {
junitVersion = '5.8.2'
}
tasks.withType(JavaCompile) {
options.encoding = 'UTF-8'
sourceCompatibility = '17'
targetCompatibility = '17'
}
application {
mainModule = 'com.prototype.simulationcrystalgrowth'
mainClass = 'com.prototype.simulationcrystalgrowth.SimulationApplication'
}
javafx {
version = '17.0.1'
modules = ['javafx.controls', 'javafx.fxml', 'javafx.web']
}
dependencies {
implementation('org.controlsfx:controlsfx:11.1.1')
implementation('com.dlsc.formsfx:formsfx-core:11.4.2') {
exclude(group: 'org.openjfx')
}
implementation('net.synedra:validatorfx:0.2.1') {
exclude(group: 'org.openjfx')
}
implementation('org.kordamp.ikonli:ikonli-javafx:12.2.0')
implementation('org.kordamp.bootstrapfx:bootstrapfx-core:0.4.0')
implementation('eu.hansolo:tilesfx:17.0.11') {
exclude(group: 'org.openjfx')
}
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")
options = ['--strip-debug', '--compress', '2', '--no-header-files', '--no-man-pages']
launcher {
name = 'app'
}
}
jlinkZip {
group = 'distribution'
}
After the "build" task is completed, the "distributions" folder appears in the build folder. It contains a zip archive with the following contents:
The bin folder contains two scripts, sh and bat.
The lib folder contains, as I understand it, all the required jar modules.
If JAVA_HOME is installed on Java 17 in my environment, then when executing the bat script, my program starts.
I expected that jlink is a kind of analogue of a more user-friendly assembly and packaging of the application, which will help to create something like an exe application launcher.
I also noticed that there are no tasks related to jlink in build.gradle is not called during the build process using the "build" task.
I tried to run them myself, and I got the same error:
I am confused by the mention of the "distributions/app" path in build.gradle, I expect there should be something else after the build.
What am I doing wrong?
What should I get at the output using jlink ?

The problem is solved.
The exclude of the org.openjfx module was removed from all dependencies.
Useful links:
https://openjfx.io/openjfx-docs/#gradle
https://github.com/openjfx/samples
https://developer.tizen.org/development/articles/openjdk-and-openjfx-installation-guide

Configure Gradle for Kotlin with Java 1.7

Ok, so I'm new to Gradle and Kotlin and I am having a hard time understanding how things glue together here...
I need to configure a project that should run on Java 7 (client limitations -_-) and I want to use Kotlin with it.
Right now I have the following build.gradle file that is working but I want to ask a few things that I couldn't find anywhere else:
buildscript {
ext {
springBootVersion = '1.5.15.RELEASE'
kotlin_version = '1.1.1'
}
repositories {
mavenCentral()
}
dependencies {
classpath "org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}"
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
}
}
apply plugin: 'java'
apply plugin: 'kotlin'
apply plugin: 'idea'
apply plugin: 'org.springframework.boot'
group = 'com.springkotlin'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 1.7
targetCompatibility = 1.7
repositories {
mavenCentral()
}
dependencies {
compile('org.springframework.boot:spring-boot-starter-data-rest')
compile('org.springframework.boot:spring-boot-starter-security')
compile('com.onelogin:java-saml:2.3.0')
compile "org.jetbrains.kotlin:kotlin-stdlib-jdk7"
runtime('org.springframework.boot:spring-boot-devtools')
testCompile('org.springframework.boot:spring-boot-starter-test')
testCompile('org.springframework.security:spring-security-test')
testCompile group: 'javax.inject', name: 'javax.inject', version: '1'
}
compileKotlin {
kotlinOptions {
jvmTarget = "1.6"
}
}
Now the questions:
I have tried using kotlin_version = '1.2.70' (released last few days!) and I got the error KotlinPluginWrapper : Unsupported major.minor version 52.0. I'm guessing then this is due to Kotlin 1.2.X only being able to "compile" (is that the word?) with Java 8+. Is that right? Is 1.1.1 the right version to use here or is there a way to use 1.2.70 that would work with Java 7? Will I be missing a lot of stuff for using it?
I want to understand the 3 kotlin stuff I had to setup on the script. Correct me please:
kotlin-gradle-plugin: Is used to define which version of Kotlin I will be using(?)
apply plugin: 'kotlin': As far as I know from Gradle, this should add tasks to work with Kotlin but running gradle tasks I didn't see anything different... So what is it really for?
kotlin-stdlib-jdk7: I'm guessing this is Kotlin lib of functions, classes, etc. What I don't understand though is the difference between stdlib and stdlib-jdk7. The documentation says it contains "addition extension functions". But which ones? Also, should I define a version for this guy? Or does it automatically picks up the kotlin-gradle-plugin version?
Thanks in advance,

Currently the compiler of the Kotlin language requires JDK 8 to run. A project compiled with Kotlin can target any Java starting from Java 6.
A recipe to setup Gradle build of a project that runs on Java 7 is following:
run Gradle with Java 8 or later
for all Kotlin compile tasks
specify jvmTarget = "1.6" in kotlinOptions
specify path to JDK 7 in jdkHome in kotlinOptions
if your project contains java code specify sourceCompatibility, targetCompatibility convention properties of the Java plugin
specify the following options of all java compile tasks:
isFork = true
forkOptions.javaHome = "<path to JDK 7>"
for all Test tasks specify executable as "<path to JDK 7>/bin/java"
The full sample:
sourceCompatibility = 1.7
targetCompatibility = 1.7
def JDK_7 = System.getenv("JDK_7") // or some other way to get path to JDK 7 installation
tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile) {
kotlinOptions {
jvmTarget = "1.6"
jdkHome = JDK_7
}
}
tasks.withType(JavaCompile) {
options.fork = true
options.forkOptions.javaHome = file(JDK_7)
}
test {
executable = "$JDK_7/bin/java"
}

Kotlin can target either Java 6 or Java 8 and I don't think this has changed. However, it is quite likely that the default has changed from Java 6 to Java 8, so try as suggested here:
compileKotlin {
sourceCompatibility = JavaVersion.VERSION_1_6
targetCompatibility = JavaVersion.VERSION_1_6
kotlinOptions {
jvmTarget = "1.6"
apiVersion = "1.2"
languageVersion = "1.2"
}
}
The version of kotlin-gradle-plugin is the version of the Kotlin compiler used to compile your code. The version of the stdlib is the version of your runtime library. It is highly recommended to use the same version here.
The apply plugin: kotlin adds some tasks under the hood - just continue using the java tasks like gradle assemble, gradle build and gradle run as they will invoke the kotlin specific tasks
kotlin-stdlib-jdk7 adds very little value - unless you use features of the java library that were introduced in java 7 and that have extensions from Kotlin's stdlib, you'll be fine to just use the default stdlib (which targets Java 6 and is a dependency of kotlin-stdlib-jdk7 anyways).

Trouble while including gradle dependency for zuul

This is my build.gradle file
buildscript {
ext {
springBootVersion = '1.4.2.RELEASE'
}
repositories {
mavenCentral()
}
dependencies {
classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
}
}
apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'org.springframework.boot'
jar {
baseName = 'yBayApplication'
version = '0.0.1-SNAPSHOT'
}
sourceCompatibility = 1.8
targetCompatibility = 1.8
repositories {
mavenCentral()
maven { url "https://repo.spring.io/snapshot" }
maven { url "https://repo.spring.io/milestone" }
}
springBoot {
mainClass = "com.ybayApplication.customerAccount.CustomerServiceApplication"
}
dependencies {
compile('org.springframework.cloud:spring-cloud-starter-eureka-server:1.2.3.RELEASE')
compile('org.springframework.cloud:spring-cloud-starter-zuul')
compile group: 'com.netflix.zuul', name: 'zuul-core', version: '2.0.0-rc.1'
compile group: 'com.netflix.governator', name: 'governator-archaius', version: '1.6.0'
compile group: 'io.reactivex', name: 'rxjava-string', version: '0.22.0'
compile('org.springframework.boot:spring-boot-starter-actuator')
compile('org.springframework.boot:spring-boot-starter-web')
testCompile('org.springframework.boot:spring-boot-starter-test')
compile("org.springframework.boot:spring-boot-starter-data-jpa")
compile("com.h2database:h2")
testCompile("junit:junit")
}
dependencyManagement {
imports {
mavenBom "org.springframework.cloud:spring-cloud-dependencies:Brixton.BUILD-SNAPSHOT"
}
}
eclipse {
classpath {
containers.remove('org.eclipse.jdt.launching.JRE_CONTAINER')
containers 'org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8'
}
}
And this is the error message, I am receiving while building the gradle.
Gradle Distribution: Local installation at C:\gradle\gradle-3.4.1
Gradle Version: 3.4.1
Java Home: C:\Program Files (x86)\Java\jdk1.8.0_121
JVM Arguments: None
Program Arguments: None
Gradle Tasks: clean build
:clean UP-TO-DATE
:compileJava FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Could not resolve all dependencies for configuration ':detachedConfiguration5'.
> Could not find com.netflix.governator:governator-archaius:1.6.0.
Searched in the following locations:
https://repo1.maven.org/maven2/com/netflix/governator/governator-archaius/1.6.0/governator-archaius-1.6.0.pom
https://repo1.maven.org/maven2/com/netflix/governator/governator-archaius/1.6.0/governator-archaius-1.6.0.jar
https://repo.spring.io/snapshot/com/netflix/governator/governator-archaius/1.6.0/governator-archaius-1.6.0.pom
https://repo.spring.io/snapshot/com/netflix/governator/governator-archaius/1.6.0/governator-archaius-1.6.0.jar
https://repo.spring.io/milestone/com/netflix/governator/governator-archaius/1.6.0/governator-archaius-1.6.0.pom
https://repo.spring.io/milestone/com/netflix/governator/governator-archaius/1.6.0/governator-archaius-1.6.0.jar
Required by:
project :
project : > com.netflix.zuul:zuul-core:2.0.0-rc.1
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
BUILD FAILED
Total time: 1.77 secs
As you can see in the build.gradle file, I have added the missing dependency as well. I am tying to implement a Zuul filter based on this example in gradle https://spring.io/guides/gs/routing-and-filtering/.

On the first look, it looks like you need to remove the
compile group: 'com.netflix.zuul', name: 'zuul-core', version: '2.0.0-rc.1'
The compile('org.springframework.cloud:spring-cloud-starter-zuul') is dependent on zuul core so it will download it.
Additionally, for the governator-archaius I don't see the version 1.6.0.
I think you meant 1.16.0. Look at the link here to grab the accurate version https://mvnrepository.com/artifact/com.netflix.governator/governator-archaius
Let me know if this solves your problem.

Gradle Error while building a scala code

I am facing one issue with gradle while building scala code.
$gradle makeJar
Error : org.gradle.api.tasks.TaskExecutionException :
Execution failed for task ':compileScala'.
Caused by : java.lang.NoClassDefFoundError: scala/Function1
$gradle -v
Gradle version - 1.6
groovy - 1.8.6
Ant - 1.8.4
ivy - 2.2.0
jvm - 1.7.0_55
OS - Linux 2.6x
My build.gradle file is below -
sourceCompatibility = '1.6'
apply plugin: 'scala'
def mypath = 'file://'+new File('test/lib').absolutePath
repositories {
flatDir dirs:"${mypath}"
}
configurations{
scalaPackage
}
sourceSets{
main{
scala{
srcDirs = ['test/src/scala']
}
}
}
dependencies {
compile fileTree(dir: mypath, includes: ['*.jar'])
}
task sourcePath{
sourceSets.main.scala.srcDirs = sourceSets.main.scala.srcDirs
sourceSets.main.java.srcDirs = []
}
task makeJar(type: Jar, dependsOn: compileScala){
archivename = "mytest.jar"
destinationDir = file("test/oplib")
from "build/classes"
classpath = configurations.scalaPackage
}
compileScala.dependsOn sourcePath
==========================================================
Here, my scala source code is present in - ./test/src/scala/test.scala
scala jar files present in - ./test/lib
expected output location - ./test/oplib
Is there anything wrong with build.gradle file which might be resulting in this error. Kindly suggest.
Many Thanks, Pralay

If you use spark-core_2.11 Version 1.2.0 you can define your dependencies as following:
repositories {
mavenCentral()
}
dependencies {
compile 'org.apache.spark:spark-core_2.11:1.2.0'
}
This dependency has Scala
org.scala-lang / scala-library / from 2.11.2 to 2.11.7
as a indirect dependency see
Maven Repository Search for spark-core

i take your build.gradle File and start it with a Gradle Wrapper with Gradle Version 2.3
first just with gradlew
Then i make 3 Corrections:
apply plugin: 'scala'
sourceCompatibility = '1.6'
def mypath = 'file://'+new File('test/lib').absolutePath
repositories {
flatDir dirs:"${mypath}"
}
configurations{
scalaPackage
}
sourceSets{
main{
scala{
srcDirs = ['test/src/scala']
}
}
}
dependencies {
compile fileTree(dir: mypath, includes: ['*.jar'])
}
task sourcePath{
sourceSets.main.scala.srcDirs = sourceSets.main.scala.srcDirs
sourceSets.main.java.srcDirs = []
}
task makeJar(type: Jar, dependsOn: compileScala){
archiveName = "mytest.jar"
destinationDir = file("test/oplib")
from "build/classes"
// classpath = configurations.scalaPackage
}
compileScala.dependsOn sourcePath
Move the Line sourceCompatibility after the Scala Plugin Import
Write archiveName instaed of archivename
Comment out classpath
Then i run gradlew tasks and gradlew makeJar without Error.

Scala projects need to declare a scala-library dependency.
Add this in your build.gralde File:
repositories {
mavenCentral()
}
dependencies {
compile 'org.scala-lang:scala-library:2.11.1'
}