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Java giving NoClassDefFoundError when importing maven package

I have a simple java code, App.java. I am trying to import the apache commons Fraction class from the apache commons math3 library. So, as a sample code, I put this in my App.java:
package myApp;
import org.apache.commons.math3.fraction.Fraction;
public class App
{
public static void main( String[] args )
{
Fraction f = new Fraction(2, 3);
System.out.println( "Hello World!" );
System.out.println( f );
}
}
Using the following POM:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>myApp</groupId>
<artifactId>Proj1</artifactId>
<version>1.0-SNAPSHOT</version>
<name>Proj1</name>
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-math3 -->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-math3</artifactId>
<version>3.6.1</version>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.1</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
<!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.7.1</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.2.4</version>
<configuration>
<!-- put your configurations here -->
</configuration>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
I have tried to put the plugin suggested by utdemir in his answer to a similar question, but in my case, when I run:
mvn package
java -cp target/Proj1-1.0-SNAPSHOT.jar myApp.App
While it apparently compiles properly, I get the following error:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/math3/fraction/Fraction
at myApp.App.main(App.java:8)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.math3.fraction.Fraction
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:636)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:182)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
... 1 more
What should I do?

Its much easier to run your app using mvn, rathen than by calling java directly. This is because in the later case you need to manually set the classpath to the correct value using the -cp flag. This can lead to errors, like in your case.
Here's how you can run your app using mvn
mvn exec:java -Dexec.mainClass="myApp.App"
More details can be found here

Maven Executable JAR with dependencies

I've got a mvn project that contains a dependency to apache commons-lang3. I managed to generate a manifest.mf for this jar file and it starts via java -jar .jar on my remote server.
However, it does not include any dependencies and I can't figure out why.
This is the pom.xml located in /workspace/ :
<project>
<modelVersion>4.0.0</modelVersion>
<groupId>com.hohmannit.phdev.midi</groupId>
<artifactId>releng</artifactId>
<version>1.0.0-SNAPSHOT</version>
<packaging>pom</packaging>
<properties>
<tycho.version>2.2.0</tycho.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.eclipse.tycho</groupId>
<artifactId>tycho-p2-director-plugin</artifactId>
<version>${tycho.version}</version>
</plugin>
</plugins>
</pluginManagement>
<plugins>
<plugin>
<groupId>org.eclipse.tycho</groupId>
<artifactId>tycho-maven-plugin</artifactId>
<version>${tycho.version}</version>
<extensions>true</extensions>
</plugin>
<!--Enable the replacement of the SNAPSHOT version in the final product configuration-->
<plugin>
<groupId>org.eclipse.tycho</groupId>
<artifactId>tycho-packaging-plugin</artifactId>
<version>${tycho.version}</version>
<executions>
<execution>
<phase>package</phase>
<id>package-feature</id>
<configuration>
<finalName>${project.artifactId}_${unqualifiedVersion}.${buildQualifier}</finalName>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.eclipse.tycho</groupId>
<artifactId>target-platform-configuration</artifactId>
<version>${tycho.version}</version>
<configuration>
<!-- Optional set the Java version your are using-->
<executionEnvironment>JavaSE-11</executionEnvironment>
<environments>
<environment>
<os>linux</os>
<ws>gtk</ws>
<arch>x86_64</arch>
</environment>
<environment>
<os>win32</os>
<ws>win32</ws>
<arch>x86_64</arch>
</environment>
<environment>
<os>macosx</os>
<ws>cocoa</ws>
<arch>x86_64</arch>
</environment>
</environments>
</configuration>
</plugin>
</plugins>
</build>
<modules>
<module>midi</module>
</modules>
</project>
And this is the pom.xml located in /workspace/midi :
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.hohmannit.phdev</groupId>
<artifactId>midi</artifactId>
<version>0.0.2-SNAPSHOT</version>
<name>midi</name>
<url>http://example.com</url>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven
defaults (may be moved to parent pom) -->
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>prepare-package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>
${project.build.directory}/midi/libs
</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>libs/</classpathPrefix>
<mainClass>
com.hohmannit.phdev.midi.App
</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
<configuration>
<release>11</release>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>3.0.0-M5</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.7.1</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
</plugins>
</pluginManagement>
</build>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>5.4.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.11</version>
<scope>compile</scope>
</dependency>
</dependencies>
</project>
The gitlab CI file looks like this:
image: maven:3-jdk-11
variables:
# This will suppress any download for dependencies and plugins or upload messages which would clutter the console log.
# `showDateTime` will show the passed time in milliseconds. You need to specify `--batch-mode` to make this work.
MAVEN_OPTS: "-Dhttps.protocols=TLSv1.2 -Dmaven.repo.local=$CI_PROJECT_DIR/.m2/repository -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN -Dorg.slf4j.simpleLogger.showDateTime=true -Djava.awt.headless=true"
# As of Maven 3.3.0 instead of this you may define these options in `.mvn/maven.config` so the same config is used
# when running from the command line.
# `installAtEnd` and `deployAtEnd` are only effective with recent version of the corresponding plugins.
MAVEN_CLI_OPTS: "--batch-mode --errors --fail-at-end --show-version -DinstallAtEnd=true -DdeployAtEnd=true"
cache:
paths:
- .m2/repository
default-job:
script:
- mvn test
except:
- tags
release-job:
script:
- mvn clean package
artifacts:
paths:
- /builds/phdev/midi-sequencer/midi/target/*.jar
only:
- tags
When this job runs through, I get a jar file with the following MANIFEST.MF:
Manifest-Version: 1.0
Archiver-Version: Plexus Archiver
Created-By: Apache Maven 3.6.3
Built-By: root
Build-Jdk: 11.0.10
Class-Path: libs/commons-lang3-3.11.jar
Main-Class: com.hohmannit.phdev.midi.App
You can see, that it correctly resolves the dependency to commons-lang and puts it into the manifest. But the actual files are missing.
Anyone knows why?

I think your maven-jar-plugin adding entries to the manifest. however, it is not bundled with the dependencies.
try adding the following plugin
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>fully.qualified.MainClass</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>

ANTLR4 CharStream class missing

I am using ANTLR4 to parse command lines for my Java Shell project.
When I run a JUnit test in VSCode, everything is fine. However, when I am building the Docker image and I try to run the shell in interactive mode, I get this error:
Error: Unable to initialize main class uk.ac.ucl.jsh.Jsh
Caused by: java.lang.NoClassDefFoundError: org/antlr/v4/runtime/CharStream
Is there any issue with my pom.xml file, or is the problem coming from somewhere else? This is my pom.xml file:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>uk.ac.ucl.jsh</groupId>
<artifactId>jsh</artifactId>
<packaging>jar</packaging>
<version>1.0-SNAPSHOT</version>
<name>jsh</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.antlr</groupId>
<artifactId>antlr4-runtime</artifactId>
<version>4.7.2</version>
</dependency>
</dependencies>
<properties>
<maven.compiler.source>11</maven.compiler.source>
<maven.compiler.target>11</maven.compiler.target>
<argLine>-XX:MaxPermSize=512m</argLine>
</properties>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>3.0.0-M3</version>
</plugin>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>0.8.4</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>uk.ac.ucl.jsh.Jsh</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<groupId>org.antlr</groupId>
<artifactId>antlr4-maven-plugin</artifactId>
<version>4.7.2</version>
<executions>
<execution>
<goals>
<goal>antlr4</goal>
</goals>
</execution>
</executions>
<configuration>
<visitor>true</visitor>
<listener>true</listener>
<outputDirectory>
${basedir}/src/main/java/
</outputDirectory>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
<reporting>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-pmd-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<reportSets>
<reportSet>
<reports>
<!-- select non-aggregate reports -->
<report>report</report>
</reports>
</reportSet>
</reportSets>
</plugin>
</plugins>
</reporting>
</project>

This doesn't really look like an ANTLR problem. You'll need to look into how you're doing your build and how you're putting your Docker image together.
There are a couple of solutions to this.
Look into how to have Maven produce an Uber jar (i.e. a jar file that bundles up all of it's dependencies)
Ensure that your Docker image has the ANTLR runtime included and in your class path.
The first of those is probably the more "normal" solutions these days.

Include JDBC driver for Postgres in the JAR fo my simple demo app driven by Maven [duplicate]

This question already has answers here:
How can I create an executable/runnable JAR with dependencies using Maven?
(33 answers)
Closed 3 years ago.
How to make Maven include the JDBC driver for Postgres inside my app's .jar file?
I added this dependency element to the <dependencies> element in my POM.
<!-- https://mvnrepository.com/artifact/org.postgresql/postgresql -->
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>42.2.8</version>
</dependency>
The IntelliJ IDE shows the driver was successfully downloaded, as it is listed in the "External Libraries" item of my Project pane. And my code can use the JDBC classes such as PGSimpleDataSource.
When I build, if I look inside the resulting .jar file, there is no JDBC driver included.
My project is driven by Maven, using the maven-archetype-quickstart archetype. I did update all the version numbers within the POM to the latest. My only other change was to add the following to get the manifest file of the JAR to specify a main class.
<configuration>
<archive>
<manifest>
<mainClass>work.basil.example.App</mainClass>
</manifest>
</archive>
</configuration>
I thought that Maven by default would bundle all dependencies inside the resulting JAR file. That is the behavior I have seen in building Vaadin web apps. Is that not the case more generally? Or is the JDBC driver special and being omitted for some reason.
If it helps, here is the entire POM.
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns = "http://maven.apache.org/POM/4.0.0"
xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation = "http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>tryjdbc</artifactId>
<version>1.0-SNAPSHOT</version>
<name>tryjdbc</name>
<description>A simple tryjdbc.</description>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>13</maven.compiler.source>
<maven.compiler.target>13</maven.compiler.target>
</properties>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter -->
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter</artifactId>
<version>5.6.0-M1</version>
<scope>test</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/org.postgresql/postgresql -->
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>42.2.8</version>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.8.2</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
<!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>3.0.0-M3</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.1.2</version>
<configuration>
<archive>
<manifest>
<mainClass>work.basil.example.App</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>3.0.0-M1</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>3.0.0-M1</version>
</plugin>
</plugins>
</pluginManagement>
</build>
<reporting>
<plugins>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
</plugin>
</plugins>
</reporting>
</project>

The .war files, such as those you saw in building Vaadin web apps, do include dependencies by default.
In contrast, the .jar files built by Maven do not include any dependencies by default.
You can use a plugin such as maven-shade-plugin to create a shaded jar, which does include the dependencies:
<project>
...
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.2.1</version>
<configuration>
<!-- put your configurations here -->
</configuration>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
...
</project>
Further examples can be found on the Apache Maven Shade Plugin project page.

Maven: Generating an executable jar file with all the dependencies

I recently converted one of my Java project to a Maven project. My pom.xml looks something like this:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<packaging>jar</packaging>
<groupId>com.myproject.groupid</groupId>
<artifactId>myproject</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>MyProject</name>
<description>The first version of my maven project</description>
<dependencies>
<dependency>
<groupId>com.dependent.jar</groupId>
<artifactId>dependentjar</artifactId>
<version>0.0.1</version>
<scope>system</scope>
<type>jar</type>
<systemPath>${project.basedir}/jars/dependent.jar</systemPath>
</dependency>
<dependency>
<groupId>org.apache.ws.commons.schema</groupId>
<artifactId>XmlSchema</artifactId>
<version>1.4.3</version>
</dependency>
<dependency>
</dependencies>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.0</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>com.myproject.main.MainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</build>
</project>
When i execute the mvn compile and mvn install, the project works fine and it also generates the jar. But when i try to run the jar [using java -jar MyProject.jar], i get an error which says: Exception in thread "main" java.lang.NoClassDefFoundError and this is because maven is not able to add the dependent jar specified in the section. [it is not available during run time]
Could anybody let me know the best possible way for me to copy the systemPath jars to the jar that is being generated by maven?
I looked at maven-shade-plugin and maven-assembly-plugin and could not find much luck with both of them. Any help would be appreciated!

Try to add this to your maven-jar-plugin configuration
<addClasspath>true</addClasspath>
<classpathPrefix>*path to dependencies*</classpathPrefix>
Also to manage your dependencies you can use Maven dependency plugin

In the build section of your pom, you can use:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.4.2</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<artifactSet>
<includes>
<include>com:library:**</include>
</artifactSet>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
Then, on the command line, you can run mvn package, it will show in the output which jars it is excluding. Then, you can include selected jars accordingly. If you then get NoClassDefFoundError, you may need to point Java to your class, by for example using com.company.Main as an argument to the java command.