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Maven-compiler-plugin throws wanted compile errors but deny the compile progress

A few days ago i started with Maven. I have to put only a few of my dependencies in my generated jar file. This is needed because my code is only a plugin (Minecraft Plugin) executed by an api (Minecraft Server Software Spigot). Now the Problem is, that my Plugin depends on an other api (json-simple-1.1).
The last days i tried to edit the maven shade plugin to get the wished result. I failed, and now i did it in this way:
maven include the json-simple-1.1 api, i needing for my plugin
eclipse include the spigot api (Minecraft server software), which will executing my plugin
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>de.falco.essentialsXXX</groupId>
<artifactId>EssentialsXXX-bungeecord</artifactId>
<version>0.0.1-SNAPSHOT</version>
<description>Basic class for every Plugin
</description>
<build>
<sourceDirectory>src</sourceDirectory>
<!-- COMPILE -->
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<!-- BUILD -->
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.1.0</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-json</descriptorRef>
</descriptorRefs>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.googlecode.json-simple</groupId>
<artifactId>json-simple</artifactId>
<version>1.1.1</version>
</dependency>
</dependencies>
</project>
When i now execute 'mvn clean install' (in the right directory) i get many many errors. That make completely sense. Maven can not find types or classes and everything else comeing from the spigot-api.
My Problem is, that this isnt a real error because when the spigot-api execute my plugin i have the classes and types i need. Maven dont know that and dont compile my Programm :(
At this point a have no idea what to do. I read so many articles but i couldnt find a solution. Every article say ohhh an error here try to use tags and the right api values. That isnt what i need.
I need something like a "bypass" attribute for the compiler so the compiler know "yes this is an error but the coder knows what he does"

If you need something for compilation, it needs to be a Maven dependency.
So take that artifact, install it in your local repository and add it as dependency.
Then your compilation process will probably work.
Note that using a dependency does not mean that you have to include the dependency into the resulting jar.

Program 5x slower as a .jar file than when ran in eclipse

Currently the speed to run a test function is about 5× slower when done with the jar file vs. doing it in Eclipse. How should I install the jar file so the speed is similar?
I am using maven. I am using outside dependencies. I just need to know what is the best code for the build (in the pom file) to make it run as fast as possible, with no concern for copy rights. The only thing I need is for the program to work on a machine without maven installed.
Also, based on the last time I asked this, I will add more info that might be useful. Java is up to date. All is stored on the C drive. There is no outputs that is slowing this down, and it is all text based. There is a lot of reading and writing on files going on that take time to do, but it took 16.6 seconds using Eclipse and 89.6 using the jar file.
Here is the pom file, including the dependencies:
<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>kov</groupId>
<artifactId>etf-creator</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<!-- to get html request for api -->
<dependency>
<groupId>com.mashape.unirest</groupId>
<artifactId>unirest-java</artifactId>
<version>1.4.9</version>
</dependency>
<!-- for a fast way to read in a file -->
<!-- https://mvnrepository.com/artifact/commons-io/commons-io -->
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.6</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<!-- https://stackoverflow.com/questions/574594/how-can-i-create-an-executable-jar-with-dependencies-using-maven -->
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>Driver</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>
</build>
</project>
Also, for someone reason it will not install when it was before. I get an error "Source option 5 is no longer supported. Use 7 or later."
I am new to Eclipse and making executable jar files on Eclipse, so I appreciate the help.

I figured it out. I needed more memory when running it.
I ran it with this and works faster now:
java -Xms512m -Xmx1024m -jar mainProgram.jar

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

a maven program is able to run successfully from eclipse but not from command prompt [duplicate]

My first use of Maven and I'm stuck with dependencies.
I created a Maven project with Eclipse and added dependencies, and it was working without problems.
But when I try to run it via command line:
$ mvn package # successfully completes
$ java -cp target/bil138_4-0.0.1-SNAPSHOT.jar tr.edu.hacettepe.cs.b21127113.bil138_4.App # NoClassDefFoundError for dependencies
It downloads dependencies, successfully builds, but when I try to run it, I get NoClassDefFoundError:
Exception in thread "main" java.lang.NoClassDefFoundError: org/codehaus/jackson/JsonParseException
at tr.edu.hacettepe.cs.b21127113.bil138_4.db.DatabaseManager.<init>(DatabaseManager.java:16)
at tr.edu.hacettepe.cs.b21127113.bil138_4.db.DatabaseManager.<init>(DatabaseManager.java:22)
at tr.edu.hacettepe.cs.b21127113.bil138_4.App.main(App.java:10)
Caused by: java.lang.ClassNotFoundException: org.codehaus.jackson.JsonParseException
at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
... 3 more
My pom.xml is 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>
<groupId>tr.edu.hacettepe.cs.b21127113</groupId>
<artifactId>bil138_4</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>bil138_4</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-core-asl</artifactId>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-core-asl</artifactId>
<version>1.9.6</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.9.6</version>
</dependency>
</dependencies>
</dependencyManagement>
</project>
Can anyone help me?

By default, Maven doesn't bundle dependencies in the JAR file it builds, and you're not providing them on the classpath when you're trying to execute your JAR file at the command-line. This is why the Java VM can't find the library class files when trying to execute your code.
You could manually specify the libraries on the classpath with the -cp parameter, but that quickly becomes tiresome.
A better solution is to "shade" the library code into your output JAR file. There is a Maven plugin called the maven-shade-plugin to do this. You need to register it in your POM, and it will automatically build an "uber-JAR" containing your classes and the classes for your library code too when you run mvn package.
To simply bundle all required libraries, add the following to your POM:
<project>
...
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.4.1</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
...
</project>
Once this is done, you can rerun the commands you used above:
$ mvn package
$ java -cp target/bil138_4-0.0.1-SNAPSHOT.jar tr.edu.hacettepe.cs.b21127113.bil138_4.App
If you want to do further configuration of the shade plugin in terms of what JARs should be included, specifying a Main-Class for an executable JAR file, and so on, see the "Examples" section on the maven-shade-plugin site.

when I try to run it, I get NoClassDefFoundError
Run it how? You're probably trying to run it with eclipse without having correctly imported your maven classpath. See the m2eclipse plugin for integrating maven with eclipse for that.
To verify that your maven config is correct, you could run your app with the exec plugin using:
mvn exec:java -D exec.mainClass=<your main class>
Update: First, regarding your error when running exec:java, your main class is tr.edu.hacettepe.cs.b21127113.bil138_4.App. When talking about class names, they're (almost) always dot-separated. The simple class name is just the last part: App in your case. The fully-qualified name is the full package plus the simple class name, and that's what you give to maven or java when you want to run something. What you were trying to use was a file system path to a source file. That's an entirely different beast. A class name generally translates directly to a class file that's found in the class path, as compared to a source file in the file system. In your specific case, the class file in question would probably be at target/classes/tr/edu/hacettepe/cs/b21127113/bil138_4/App.class because maven compiles to target/classes, and java traditionally creates a directory for each level of packaging.
Your original problem is simply that you haven't put the Jackson jars on your class path. When you run a java program from the command line, you have to set the class path to let it know where it can load classes from. You've added your own jar, but not the other required ones. Your comment makes me think you don't understand how to manually build a class path. In short, the class path can have two things: directories containing class files and jars containing class files. Directories containing jars won't work. For more details on building a class path, see "Setting the class path" and the java and javac tool documentation.
Your class path would need to be at least, and without the line feeds:
target/bil138_4-0.0.1-SNAPSHOT.jar:
/home/utdemir/.m2/repository/org/codehaus/jackson/jackson-core-asl/1.9.6/jackson-core-asl-1.9.6.jar:
/home/utdemir/.m2/repository/org/codehaus/jackson/jackson-mapper-asl/1.9.6/jackson-mapper-asl-1.9.6.jar
Note that the separator on Windows is a semicolon (;).
I apologize for not noticing it sooner. The problem was sitting there in your original post, but I missed it.

You have to make classpath in pom file for your dependency. Therefore you have to copy all the dependencies into one place.
Check my blog.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.1</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/lib</outputDirectory>
<overWriteReleases>false</overWriteReleases>
<overWriteSnapshots>false</overWriteSnapshots>
<overWriteIfNewer>true</overWriteIfNewer>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.4</version>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>$fullqualified path to your main Class</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>

This is due to Morphia jar not being part of your output war/jar. Eclipse or local build includes them as part of classpath, but remote builds or auto/scheduled build don't consider them part of classpath.
You can include dependent jars using plugin.
Add below snippet into your pom's plugins section
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>

For some reason, the lib is present while compiling, but missing while running.
My situation is, two versions of one lib conflict.
For example, A depends on B and C, while B depends on D:1.0, C depends on D:1.1, maven may
just import D:1.0. If A uses one class which is in D:1.1 but not in D:1.0, a NoClassDefFoundError will be throwed.
If you are in this situation too, you need to resolve the dependency conflict.

I was able to work around it by running mvn install:install-file with -Dpackaging=class. Then adding entry to POM as described here:

Choosing to Project -> Clean should resolve this

Maven Modules assembly/shade build

I have the following module structure:
powercontrol
powercontrol-core
pom.xml
powercontrol-data
pom.xml
powercontrol-gui
pom.xml
powercontrol-ui
pom.xml
pom.xml
Now I want that the GUI (Graphical User Interface) and UI (Command Line User Interface) can be executed by the client.
I tried to use the maven shade plugin inside the GUI and UI, but this makes it really a mess.
I prefer:
A jar file with all the third party dependencies (log4j etc).
A jar file (or maybe lib folder?) with all the project modules.
A'n executor for the GUI and UI.
Example:
powercontrol/
bin/
gui
ui
lib/
third-party.jar
powercontrol-core.jar
powercontrol-data.jar
powercontrol-gui.jar
powercontrol-ui.jar
I'm a bit stuck with getting a good structure now, where should I start?
All feedback, suggestions etc are welcome. Thank you in advance!
UPDATE 8/28/2015
I made a new module named: powercontrol-dist that will be executed as last in the Maven lifecycle. This module will generate a lib folder and copy all the dependencies from the powercontrol-gui and powercontrol-cli to this folder.
Now I have 2 questions!
Question 1
Is this a good way to go? Or is there a better way?
powercontrol-dist/pom.xml
<?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>
<parent>
<groupId>nl.nberlijn.powercontrol</groupId>
<artifactId>powercontrol</artifactId>
<version>1.0</version>
</parent>
<artifactId>powercontrol-dist</artifactId>
<packaging>pom</packaging>
<name>PowerControl Dist</name>
<description>Dist</description>
<dependencies>
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>powercontrol-gui</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>powercontrol-cli</artifactId>
<version>${project.version}</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.10</version>
<executions>
<execution>
<id>copy</id>
<phase>package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/lib</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
Output:
powercontrol/
bin/
gui.exe
ui.exe
lib/
third-party-lib.....jar
third-party-lib.....jar
third-party-lib.....jar
powercontrol-core.jar
powercontrol-data.jar
powercontrol-gui.jar
powercontrol-cli.jar
Question 2
Also I want to make two .exe files "gui.exe and cli.exe" referencing to the powercontrol-gui.jar and the powercontrol-cli.jar.
Is adding a mainclass to the manifest inside the pom.xml in the powercontrol-gui and powercontrol-cli module enough?
<build>
<plugins>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>${main.class}</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>

If you want two executable JARs (gui.jar, ui.jar), you should add the shade plugin to those two modules, so that as part of each module, a standalone executable JAR is built. Both of the JARs will contain all the third-party stuff as well. You cannot create a standalone executable JAR where parts of the dependencies are in an external JAR (unless you do you own classloader magic or unless you also have to specify the external JAR on the command line).
If you are stuck with the maven shade plugin, you should tell us what problem exactly you have. Typically these can be resolved. A common problem is that certain files need to be "merged" when a shaded JAR is created, in particular files in META-INF e.g. used by Spring or by the Java Service Locator mechanism. The shade plugin offers support for such merging, but it needs to be configured for the case at hand.
Btw. I'd recommend calling the command line version "cli.jar" - "ui" sounds like "gui".
Ok, since you updated your question and now seem to be asking for a "native launcher" (exe file) instead of an executable JAR file - those are completely different things.
Launching an exe file from the command line:
C:\> gui
Launching an executable JAR file from the command line
C:\ java -jar gui.jar
To get the first, you need to create a native launcher that internally invokes Java. A project that might support you in that task could be launch4j - they also seem to provide a Maven plugin.