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Create jar A without dependencies and make dependent project C download the dependency B that this dependency A depends on

I have successfully created jar A that does not contain dependencies. This jar A depends on Jar B. I don't want to create a fat jar. I just want dependent project (lets call it C) to add my jar A as dependency, and as soon as jar A is added, project should pull in jar B.
Is this possible?
Question ends here. Below is just what I have tried so far:
What I have done:
I created Fat Jars first with both maven and gradle. Now this has all the dependencies, but my own classes are buried somewhere inside. And dependent project cannot find my classes.
Then I created a jar that does not contain any dependency. I created them separately with maven and gradle. This resolved my classes not being found issue. But then I ran into another issue. As soon as I run the project, it complains that jar B is missing. Rightfully so, as I never included it.
I will just show you my pom.xml
<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>custom-spring-boot-starter</groupId>
<artifactId>custom-spring-boot-starter</artifactId>
<version>0.0.1-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
<scope>provided</scope>
</dependency>
<dependency> //THIS IS WHAT DEPENDENT PROJECT WILL NOT HAVE.
<groupId>com.microsoft.azure</groupId>
<artifactId>azure-servicebus</artifactId>
<version>0.9.7</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
<configuration>
<release>10</release>
</configuration>
</plugin>
</plugins>
</build>
This created a jar without dependencies. I added it to dependent project C. But it is complaining that it cannot find dependent B (azure-servicebus in my example). I was hoping that because pom.xml file is present in the jar file, dependent project will download another dependency automatically.
Then I rewrote my pom.xml:
<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>custom-spring-boot-starter</groupId>
<artifactId>custom-spring-boot-starter</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>10</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.microsoft.azure</groupId>
<artifactId>azure-servicebus</artifactId>
<version>0.9.7</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
<configuration>
<release>10</release>
</configuration>
</plugin>
<plugin>
<groupId>pl.project13.maven</groupId>
<artifactId>git-commit-id-plugin</artifactId>
<executions>
<execution>
<id></id>
<goals>
<goal>revision</goal>
</goals>
<phase>validate</phase>
</execution>
</executions>
<configuration>
<dateFormat>yyyy-MM-dd-HH:mm:ss</dateFormat>
<dotGitDirectory>${project.basedir}/.git</dotGitDirectory>
<prefix>git</prefix>
<verbose>false</verbose>
<generateGitPropertiesFile>true</generateGitPropertiesFile>
<generateGitPropertiesFilename>${project.build.outputDirectory}/git.properties</generateGitPropertiesFilename>
<format>json</format>
<gitDescribe>
<skip>false</skip>
<always>false</always>
<dirty>-dirty</dirty>
</gitDescribe>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifestEntries>
<Build-Jdk>${java.version} (${java.vendor} ${java.vm.version})</Build-Jdk>
<Digital-Voltage-Library-Version>${project.version}</Digital-Voltage-Library-Version>
<Build-Timestamp>${git.build.time}</Build-Timestamp>
<Build-Revision>${git.commit.id}</Build-Revision>
<Build-OS>${os.name} ${os.arch} ${os.version}</Build-OS>
</manifestEntries>
</archive>
</configuration>
</plugin>
</plugins>
</build>
This is the stacktrace of the error:
Caused by: java.lang.ClassNotFoundException: com.microsoft.windowsazure.services.servicebus.ServiceBusContract
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:190)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:374)
at org.springframework.util.ClassUtils.forName(ClassUtils.java:275)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$BeanSearchSpec.getReturnType(OnBeanCondition.java:505)
at org.springframework.boot.autoconfigure.condition.OnBeanCondition$BeanSearchSpec.addDeducedBeanTypeForBeanMethod(OnBeanCondition.java:491)
... 22 common frames omitted
This error easily goes away if I add azure-servicebus dependency to target project. But I don't want to do that. I want the dependency to pull in azure-servicebus.
This is how I am pulling in my jar A into project C.
compile fileTree(dir: '/lib', include: 'custom-spring-boot-starter-0.0.1-SNAPSHOT.jar')

Yes, if A has a Maven dependency on B, then B is automatically pulled when C depends on A. This is the Maven transitive dependency resolution.
Note that this has nothing to do with fat jars. B is not included in A, it is just mentioned as dependency in the POM of A.

I asked this question without knowing something very important.
When jars are put into artifactory, a corresponding .pom file also has to be placed alongside it (outside of the directory, just look at below link to understand directory structure). This pom file is what tells the dependent project that the jar you are dependent upon, requires so and so dependencies itself.
If you do mvn clean install, it automatically installs jar file and pom file at the correct location for you in your local maven repository.
This answer helped me understand:
https://stackoverflow.com/a/50002072/4828463
Thanks to everyone who tried.

Maven - Executable file from a java project

I need to use maven (for a school project) to create an executable file from a single maven command. I've never used maven and tried many solutions here on stackoverlow. The solutions created a jar file, but the file never opened.
This is my project structure
src
com
project
code
swing
programm
interface
Main.class
I know this isn't maven convention, however changing it now would mean I would have to adjust the imports (as intelliJ doesn't refactor everything perfectly) for around 40 classes.
<?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>MyGroup</groupId>
<artifactId>myProgramm</artifactId>
<version>0.7-SNAPSHOT</version>
<packaging>jar</packaging>
<name>Hello World</name>
<description>Course Project</description>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.xerial/sqlite-jdbc -->
<dependency>
<groupId>org.xerial</groupId>
<artifactId>sqlite-jdbc</artifactId>
<version>3.25.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.junit/junit5-engine -->
<dependency>
<groupId>org.junit</groupId>
<artifactId>junit5-engine</artifactId>
<version>5.0.0-ALPHA</version>
</dependency>
</dependencies>
<build>
</build>
What do I have to put inside to make an executable file?

TimurJD's answer is correct however I would like to explain step by step what is actually happening and why.
To have a jar be executable the JVM needs to know where your main method is.
For that you need a file called META-INF/MANIFEST.MF inside the jar you create.
This file must contain a reference to the class containing your main method which is done like this:
Main-Class: com.example.ClassContainingMainMethod
There are many ways of creating said file but since you are using maven here is the plugin that will help you create this manifest file
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.1.1</version>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>com.my.packege.Main</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
Once you have the plugin in your pom.xml simply run the maven install goal, either from your IDE or the command line. After you should find a folder called target in your project. That folder will contain the executable jar.
To run the jar you can call from the command line:
java -jar MyProject.jar
It should also be noted that unless you abide by the maven standard of keeping your source code in src/main/java you will have to specify your source folder explicitly.

You need to add plugin to your pom.xml file
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<configuration>
<mainClass>com.example.Main</mainClass>
</configuration>
</plugin>
</plugins>
</build>
and to run the program: mvn clean install exec:java
... here is the link for doc http://www.mojohaus.org/exec-maven-plugin/usage.html
There are possible different solutions, depends on your requirements: https://www.baeldung.com/executable-jar-with-maven

unable to satisfy dependency from com.lmax.disruptor 3.2.0 to package sun.misc 0.0.0

I am developing an eclipse plugin which needs an com.lmax.disruptor.It imports sun.misc. I have this in my p2 repository but when I maven build my plugin I am getting this error "unable to satisfy dependency from com.lmax.disruptor 3.2.0 to package sun.misc 0.0.0."
I have gone through the sites Resolve a dependency on package sun.misc with Tycho they are saying to create a plugin fragment but when I tried to create it and added export page as sun.misc, It is throwing an error like "package sun.misc doesnot exsist in the plugin".
How can solve this issue please help me with this.? Instead of creating new plugin fragment,is there is any possible way i can add in my plugin itself ?
Thanks,

As mentioned in oberlies' answer in the question you link to, you need to build a system bundle fragment, which exposes, i.e., exports, the sun.misc package. I don't know of any other way. However, this is easier than could be expected.
You do this by creating an OSGi MANIFEST.MF that exports sun.misc, and then bundle it into a fragment. This is done via Maven as follows.
<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>your.group</groupId>
<version>1.0.0</version>
<artifactId>your.group.fragment.sun.misc</artifactId>
<packaging>jar</packaging>
<name>System Bundle Fragment exporting sun.misc</name>
<description>This bundle extends the System Bundle export list with the sun.misc package such that OSGi bundles may refer to Sun's misc implementation without the OSGi framework itself to provide it in a non-portable way.</description>
<build>
<plugins>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<forceCreation>true</forceCreation>
<archive>
<manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
<manifestEntries>
<Export-Package>sun.misc</Export-Package>
</manifestEntries>
</archive>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.felix</groupId>
<artifactId>maven-bundle-plugin</artifactId>
<version>2.5.4</version>
<executions>
<execution>
<id>bundle-manifest</id>
<phase>process-classes</phase>
<goals>
<goal>manifest</goal>
</goals>
</execution>
</executions>
<configuration>
<instructions>
<Bundle-Category>your.group</Bundle-Category>
<Fragment-Host>system.bundle; extension:=framework</Fragment-Host>
</instructions>
</configuration>
</plugin>
</plugins>
</build>
</project>
Run mvn clean install on this POM. Now you need to make the fragment consumable for Tycho, i.e., you need to make it available via a p2 Software Site.
Thankfully there is a great Maven plugin which can help with that: reficio's p2-maven-plugin. You can use it to basically wrap any mavenized JAR into an OSGi bundle and then provide it via a p2 site.
Set up the respective POM as follows.
<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>sun-misc-p2</groupId>
<artifactId>site</artifactId>
<version>1.0.0</version>
<packaging>pom</packaging>
<build>
<plugins>
<plugin>
<groupId>org.reficio</groupId>
<artifactId>p2-maven-plugin</artifactId>
<version>1.1.1</version>
<executions>
<execution>
<id>default-cli</id>
<configuration>
<artifacts>
<!-- specify your depencies here -->
<!-- groupId:artifactId:version -->
<artifact><id>com.lmax:disruptor:3.3.2</id></artifact>
<artifact><id>your.group:your.group.fragment.sun.misc:1.0.0</id></artifact>
</artifacts>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.mortbay.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>8.1.5.v20120716</version>
<configuration>
<scanIntervalSeconds>10</scanIntervalSeconds>
<webAppSourceDirectory>${basedir}/target/repository/</webAppSourceDirectory>
<webApp>
<contextPath>/site</contextPath>
</webApp>
</configuration>
</plugin>
</plugins>
</build>
<pluginRepositories>
<pluginRepository>
<id>reficio</id>
<url>http://repo.reficio.org/maven/</url>
</pluginRepository>
</pluginRepositories>
</project>
Note that I use this plugin to provide the LMAX Disruptor (version 3.3.2, the latest one at the time of writing, is thankfully available from Maven Central).
Run mvn p2:site on the POM. This will create a p2 site containing the sun.misc fragment at {project-folder}/target/repository.
This p2 repository - and with it the sun.misc fragment - can now be added to your target platform, and hence used in your Tycho build.
This should fix it, and - to answer your question if "there is any possible way [you] can add in [your] plugin itself" - this is the only possible way to do it (I know of).
The sources are also available at https://github.com/newcodeontheblock/eclipse-rcp-with-async-logging. The whole procedure is also described in more detail in this - my - blog post about using async Log4j 2 loggers in an Eclipse RCP.

Building a maven project for deployment

Hello all I'm pretty new to using maven to build Java project so I'm sure the solution to my problem will be quite easy. I have installed the Eclipse Maven plugin and created a maven project. I now wish to package this project and distribute it as a runnable jar file. However when I run
mvn package
and then try to run the jar file I get the following error:
Exception in thread "main" java.lang.NoClassDefFoundError: main/Formatter
The pom for this particular file looks like so:
<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>GROUP</groupId>
<artifactId>pcap.csv.xml</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>net.sf.opencsv</groupId>
<artifactId>opencsv</artifactId>
<version>2.0</version>
</dependency>
</dependencies>
</project>
Any help would be greatly appreciated.

You need to specify the main class in the jar plugin:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<mainClass>main.Formatter</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
If you want to distribute a single jar you need to use a single-jarifier (fatjar, jarjar, onejar, etc.)

maven 3 interproject depedency with war packaging

I have Eclipse Indigo and M2E plugin installed.
So essentially I have a standard maven web project (let's call it proj-service) that is built into a war file in the package phase. This all works fine. My issue comes in when I have my other project (lets call it proj1) that needs to use classes from proj-service. I know that this is possible in maven+eclipse but it does not seem to be working at the moment. I have the following in proj1's pom right now:
<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>com.mycompany.foo</groupId>
<artifactId>proj1</artifactId>
<packaging>war</packaging>
<version>1.0</version>
<name>proj1</name>
<properties>
<spring.version>3.1.0.RELEASE</spring.version>
</properties>
<dependencies>
<!-- Maven Repo Libraries -->
.........
<!-- Interproject dependencies -->
<dependency>
<groupId>com.mycompany.foo</groupId>
<artifactId>proj-service</artifactId>
<version>1.0</version>
<type>war</type>
</dependency>
</dependencies>
<build>
<finalName>lsoap</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
</project>

Unfortunately with Maven's war packaging you can't reuse classes from war project, because there is no direct build artifact you can use for the class path.
So, in order to do share classes properly you need to extract those common classes into a 3rd common project (jar packaging) and make it as dependency in both of your other projects.

First you have to change the configuration of your proj-service project in the way to change the configuration of the maven-war-plugin:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<configuration>
<attachClasses>true</attachClasses>
<archiveClasses>true</archiveClasses>
...
</configuration>
</plugin>
This will it make possible to use the classes from the proj-service project in other projects via the following dependencies:
<dependency>
<groupId>myGroup</groupId>
<artifactId>myArtifact</artifactId>
<version>myVersion</myVersion>
<classifier>classes</classifier>
</dependency>
This will result in changing your dependency from:
<dependency>
<groupId>com.mycompany.foo</groupId>
<artifactId>proj-service</artifactId>
<version>1.0</version>
<type>war</type>
</dependency>
into:
<dependency>
<groupId>com.mycompany.foo</groupId>
<artifactId>proj-service</artifactId>
<version>1.0</version>
<classifier>classes</classifier/>
</dependency>