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Netbeans 8.2 and maven - no main manifest attribute error

i am using netbeans 8.2 to create a simple java project. i've chosen Maven-Java Application. I've created a simple hello world java class. I've selected the java class as the main class from Properties -> Run and if i run the project from Netbeans, it print the hello world. After that, i do "Clean" and "Build with dependencies" the editor create a target folder with the jar file. When i go to that folder and execute "java -jar XXX.jar", i get the no main manifest attribute error. Do I have to manually update the POM.xml file? Am I missing a step?

I am answering my own question.
Apparently you have to manually update the pom.xml file. I've added the dependency for maven-jar-plugin and added below section to the pom.xml file.
<build>
<plugins>
<plugin>
<!-- Build an executable JAR -->
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.1.0</version>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>com.mypackage.XXX</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>

Maven: Could not find or load main class

I have the following configuration for my maven build and I have double checked the class name as well as package name multiple times to ensure it's accuracy. But everytime I run:
java -jar <snapshot-with-dependencies>.jar I get Error: Could not find or load main class com.atlassian.JiraRestCaller.
The excerpt from my pom file is as below
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>com.atlassian.JiraRestCaller</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
I also tried adding <sourceDirectory>src/main/java/com/atlassian/</sourceDirectory> but still get the same error

Solution1:
I spent a decent amount of time trying to solve this problem. I thought that I was somehow setting my classpath incorrectly but the problem was that I typed:
java -cp C:/java/MyClasses C:/java/MyClasses/utilities/myapp/Cool
instead of:
java -cp C:/java/MyClasses utilities/myapp/Cool
I thought the meaning of fully qualified meant to include the full path name instead of the full package name.
Solution2:
If you use Maven to build the JAR file, please make sure to specify the main class in the pom.xml file:
<build>
<plugins>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>class name us.com.test.abc.MyMainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>

This might help you if your case is specifically like mine: as a beginner I also ran into this problem when I tried to run a Java program.
I compiled it like this:
javac HelloWorld.java
And I tried to run also with the same extension:
java Helloworld.java
When I removed the .java and rewrote the command like java HelloWorld, the program ran perfectly. :)

So we had this today
[myproject]-[master] $ mvn
[MVNVM] Using maven: 3.5.2
Error: Could not find or load main class html
and we had an issue with Proxies.
Check your MAVEN_OPTS and make sure that if you are sending in a proxy to maven, that it exists and you can use it.
MAVEN_OPTS=-Dhttp.proxyHost=www-proxy.myproxyprovider.com -Dhttp.proxyPort=80 -Dhttps.proxyHost=www-proxy.myproxyprovider.com -Dhttps.proxyPort=80
or if it is set and you shouldnt have one, then get rid of it.
[myproject]-[master] $ mvn -version
[MVNVM] Using maven: 3.5.2
Apache Maven 3.5.2 (138edd61fd100ec658bfa2d307c43b76940a5d7d; 2017-10-18T08:58:13+01:00)
Maven home: /Users/bamcgill/.mvnvm/apache-maven-3.5.2

I experienced the same error. I fixed it by upgrading from Maven 3.3.3 to Maven 3.6.3. I am not sure whether that fix is related to this question, because I did not debug my issue.

Setting classpath for a java project with many libraries and external resources in command line

I have the following project. It has some property files in the conf folder, some data in the data folder, some jar files in the lib folder and also some external libraries that are not shown in the photo due to size limitation. Imagine I want to run the RecDriver class. How exactly should I set the classpath so that I can run it in command line? This is how I did it but it does not work as it cannot fine some other files in the project.
C:\Users\myUserName\Downloads\librec-2.0.0\librec-2.0.0\core\src\main\java\net\librec\tool\driver> javac RecDriver.java
The project can be downloaded here:
https://github.com/guoguibing/librec

You can use bin/librec or bin/librec.cmd to run it from commandline.
If you want to build your launch command you can see those start scripts and adapt them for your purposes.

To run your app through command line, once you have the .class files in some dir (usually build) all you have to do is run your application with java -cp "path where jvm can find every .class that you project needs" MainClass.
The -cp flag only tells where to look for compiled .class files, since you are using IntellIJ you can see the command it runs when executing your program, there is a class path that it uses.
Class Path points to where your .class files are, they can be in separate folders, but you need to include every dir when giving the class path, separated by ";"
Example taken from another question in SO.
java -cp "Test.jar;lib/*" my.package.MainClass

Three things to do:
Use the Maven Shade Plugin to create a fat jar (jar with dependencies)
Use the Maven-Jar-Plugin to make the Jar executable
Set <project><build><finalName> to ${artifactId}
Now, after your build ran successfully, you can run your app with
java -jar target/YourArtifactId.jar
(Substitute your project's artifactId for "YourArtifactId")
Okay, here's the full setup.
Add a build section like this to your pom.xml (merge it with any existing one).
<build>
<plugins>
<!-- number 1 -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.0.0</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<minimizeJar>true</minimizeJar>
</configuration>
</execution>
</executions>
</plugin>
<!-- number 2 -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.2</version>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<mainClass>fully.qualified.MainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
<!-- number 3 -->
<finalName>${project.artifactId}</finalName>
</build>

Java remote debugging with Maven and Netbeans

I'm trying to remotely debug a jar file bundled with dependencies created with maven-assembly-plugin. But everything I do, and no matter how I call the debugger on the machine running the code (or on my local machine for testing) I always get a "Could not find main class". That's the message even if I specify the exact main class in the command line.
POM file:
<build>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>com.xxx.yyy.MyMainClass</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
</build>
I'm creating the jar with dependencies with:
clean compiler:compile assembly:single
The debugging is started with:
java -Xdebug -Xrunjdwp:transport=dt_socket,address=8800,server=y,suspend=y -classpath %classpath com.xxx.yyy.MyMainClass pubsubtest-0.1-jar-with-dependencies.jar
The application starts and says:
Listening for transport dt_socket at address: 8800
But when I connect to the port with Netbeans the issue is:
Error: Could not find or load main class com.xxx.yyy.MyMainClass
Am I missing something? Should I setup Netbeans somehow? In Netbeans I'm keeping the project open.
I followed this tutorial:
https://blogs.oracle.com/atishay/entry/use_netbeans_to_debug_a

Running jar, setting classpath

I've got a project I've made with Maven. I compile a JAR, with "mvn package", and now I want to run it, preferably without setting some insane classpath, as it depends on Spring and half the internet or something. Is there any way I can run it easily? Something like "mvn run" would be great, or an option to throw in all dependencies into the jar so I can do "java -jar" would also be splendid.
How do you deal with this, and what do you recommend doing? Because exporting a CLASSPATH based on ~/.m2 would probably just be hurtful ;-)

Setting CLASSPATH and calling java -jar myjar.jar wouldn't work anyway. Because the java -jar command ignores the CLASSPATH environment variable as well as the -cp flag.
In this case you had to add the classpath entries to the jar's MANIFEST at the Class-Path key, like:
Class-Path: jar1-name jar2-name directory-name/jar3-name

Use the Maven Assembly Plugin - it will automatically build your JAR with all included dependencies, and you can set the main class parameter to make the JAR executable.
The documentation can be confusing, so here is an example of what your POM will look like:
<build>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.1</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<archive>
<manifest>
<mainClass>package.of.my.MainClass</mainClass>
<packageName>package.of.my</packageName>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
And then you can run as:
mvn assembly:assembly

You will want to look into the Maven Assembly Plugin. And then once you have created the XML file required by the plugin and have modified your POM file to work with the plugin, you can run it with:
mvn assembly:assembly
This will create the JAR with all of its dependencies.