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Cannot build any maven project with same error

It has been few weeks since I build anything in maven, and I just tried to build one of the projects and it gives me this error. I try with multiple project and they are throwing same error:
Execution default of goal org.codehaus.mojo:aspectj-maven-plugin:1.8:compile failed: Plugin org.codehaus.mojo:aspectj-maven-plugin:1.8 or one of its dependencies could not be resolved: Could not find artifact com.sun:tools:jar:15.0.2 at specified path /usr/local/Cellar/openjdk/15.0.2/libexec/openjdk.jdk/Contents/Home/../lib/tools.jar -> [Help 1]
How can I resolve this error? I can't even run mvn install -DskipTests or mvn package.
I am on JDK version 8.
Edit: here is my plugin from pom:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>aspectj-maven-plugin</artifactId>
<version>${aspectj-maven-plugin.version}</version>
<configuration>
<complianceLevel>${java.version}</complianceLevel>
<source>${java.version}</source>
<target>${java.version}</target>
<showWeaveInfo>true</showWeaveInfo>
<verbose>true</verbose>
<aspectLibraries>
<dependency>
<groupId>com.jcabi</groupId>
<artifactId>jcabi-aspects</artifactId>
</dependency>
</aspectLibraries>
</configuration>
<executions>
<execution>
<goals>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
java version = 1.8
aspectj-maven-plugin.version = 1.8
EDIT: I pull this project from the repo, which means it works on other people's computer/on jenkins. I believe this is something to do with my local computer. It also gives me same error if I use terminal.

I found the answer after more research. As #Michael Katt mentioned in the comment, my JAVA_HOME wasn't properly set up. When I did which java, it gave me /usr/bin/java, but when I did echo $JAVA_HOME, it gave me nothing.
So with help of other colleague, I did vi ~/.bash_profile and added export JAVA_HOME=$(/usr/libexec/java_home). Not exactly sure why, but it is something to do with matching it with my jdk in my project structure which has /Library/Java/JavaVirtualMachines/adoptopenjdk-8.jdk...
I opened new shell and typed echo $JAVA_HOME and it gives me /Library/Java/JavaVirtualMachines/adoptopenjdk-8.jdk/Contents/Home. My project build/compiles now.
I am still not sure how $(/usr/libexec/java_home) translated to /Library/Java/JavaVirtualMachines/adoptopenjdk-8.jdk...

Error when running docker container "NoClassDefFoundError"

I am trying to dockerize a simple Spring Boot Application, built with Maven.
Dockerfile:
FROM openjdk:latest
COPY target/backend-1.0-SNAPSHOT.jar app.jar
ENTRYPOINT ["java","-jar","app.jar"]
When I run the .jar without the container (java -jar target/backend-1.0-SNAPSHOT.jar), everything works fine and the app is running.
Now I create the container with docker build -t company/backend .
But when I try to run the docker container with docker run -p 8080:8080 company/backend the following error occurs:
Exception in thread "main" java.lang.NoClassDefFoundError: org/springframework/boot/SpringApplication
at de.company.backend.Application.main(Application.java:10)
Caused by: java.lang.ClassNotFoundException: org.springframework.boot.SpringApplication
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:602)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
... 1 more
It seems like docker does not find the main class, even though it is defined in my pom.xml:
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<mainClass>de.elbdev.backend.Application</mainClass>
</properties>
<build>
<plugins>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<phase>install</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/lib</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>${mainClass}</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
Main Class:
package de.company.backend;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}

In your pom.xml, the copy-dependencies goal is specified at the install phase : too late the package of the jar was already done.
I am trying to dockerize a simple Spring Boot Application, built with
Maven.
You don't need to declare any plugin to create a fat jar with spring boot that could be run by a docker container.
Declaring these plugins is error prone (and should be used only in corner cases) while the repackage goal of the spring boot maven plugin attached by default to the package phase of maven will create for you the fat jar :
Repackages existing JAR and WAR archives so that they can be executed
from the command line using java -jar
Juste remove these plugins declarations and execute mvn clean package and it should be good.
Side note :
FROM openjdk:latest
Don't use latest as image version but favor a specific version of the image othewhise you could have bad surprises. As you use JDK 8, you could specify a JRE or a JDK 8 such as : FROM openjdk:8-jre-alpine.

I had the same problem as you.
you need to add plugin in your pom.xml.
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
If you input as above, it works normally.
and check MANIFEST.MF (in .jar file)
Main-Class: org.springframework.boot.loader.JarLauncher
Start-Class: {your main class}

Running Java program using mvn through command line

I am trying to run my java program TopicPublisher.java via command line. There are several dependencies specified through Maven.
In the directory with the pom.xml file, I ran the following commands: mvn clean, mvn package, and java -cp target/SOM_Enrichment-1.0-SNAPSHOT.jar TopicPublisher.
I get the following error:
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.NoClassDefFoundError: om/solacesystems/jcsmp/JCSMPStreamingPublishEventHandler
Below is a screenshot of my directory tree:
Any ideas how to solve this?
[EDIT]
Pom File:
<?xml version="1.0" encoding="UTF-8"?>
http://maven.apache.org/xsd/maven-4.0.0.xsd">
4.0.0
<groupId>CAMM</groupId>
<artifactId>SOM_Enrichment</artifactId>
<version>1.0-SNAPSHOT</version>
<build>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.1.0</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
<executions>
<execution>
<id>make-assembly</id> <!-- this is used for inheritance merges -->
<phase>package</phase> <!-- bind to the packaging phase -->
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.solacesystems</groupId>
<artifactId>sol-jcsmp</artifactId>
<version>[10,)</version>
</dependency>
</dependencies>

Your program loads classes from the com.solacesystems dependency in your pom.xml, but your classpath only contains your build artifact jar. Build a fat jar, as #Kerry suggests, or use the exec-maven-plugin to run from the command line. From within your project directory (where you execute mvn package), execute:
mvn exec:java -Dexec.mainClass=TopicPublisher
The plugin builds the classpath argument from the dependencies defined in your pom. See https://www.mojohaus.org/exec-maven-plugin/ for more options.

Without seeing your full POM.xml I am assuming you have not build the final artifact to be a 'fat jar'. By this I mean that the JAR not only contains your own classes but all the third party dependencies.
You would need to use something like the Maven assembly plugin or the Maven shade pluginto do this for you. From the screenshot though I see you are using IntelliJ so you should also be able to run through your IDE obviously for just testing purposes.

set the default jdk for maven-compiler-plugin

I have just installed maven on an new ubuntu system, which includes the maven-compiler-plugin. I have a java project that was previously building fine, defaulting to a javac source and target of 5 (jdk 1.5). However, the project is now trying to compile using jdk1.3 on the new system. Is there an easy way to configure the system to use >=jdk5 ?
Here's some of the configuration details of the system:
$ java -version
java version "1.6.0_45"
$ dpkg -s maven
Package: maven
Status: install ok installed
Priority: optional
Section: java
Installed-Size: 1489
Maintainer: Ubuntu Developers <ubuntu-devel-discuss#lists.ubuntu.com>
Architecture: all
Version: 3.0.4-2
$ dpkg -s libmaven-compiler-plugin-java
Package: libmaven-compiler-plugin-java
Status: install ok installed
Priority: optional
Section: java
Installed-Size: 75
Maintainer: Ubuntu Developers <ubuntu-devel-discuss#lists.ubuntu.com>
Architecture: all
Source: maven-compiler-plugin
Version: 2.0.2-6
I've checked the maven-compiler-plugin-2.0.2.pom file, and plexus-compiler-javac.originalVersion and others are set to 1.5.3.
I know I can set this on a per-project basis by including a source/target tag in a plugin context, but I'd like to configure maven-compiler to default to jdk5 or higher without having to do this across a large number of projects.
how can i do this?

In your pom specify the following to set the compiler to JDK5:
<properties>
<maven.compiler.source>1.5</maven.compiler.source>
<maven.compiler.target>1.5</maven.compiler.target>
</properties>
i.e.
<project>
<properties>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
...
</project>
I specify mine prior to the dependencies, although so long as its part of the project element you should be able to place it anywhere inside the pom.
I ran into a similar issue with Maven previously, this fixed it for me. Essentially what this does is set the -source and -target flags to the value specified and passes it to the compiler. Newer plugins default to 1.5.
In order to use the default approach without specifying the properties, you will need to be running a later version of Maven.
I suppose you could also set up a template via your IDE to include this in all new pom files. Of course the actual implementation would depend upon your IDE...
See The apache maven compiler plugin documentation as well as Setting the source and compiler examples for more details.

I tried the maven-compiler-plugin approach and it proved cumbersome as there are plugins like maven-surefire-plugin and maven-cobertura-plugin which still fail due to incompatibility issues.
The better approach was to use maven-toolchain-plugin.
Step 1
Create /.m2/toolchains.xml
<?xml version="1.0" encoding="UTF8"?>
<toolchains>
<!-- JDK toolchains -->
<toolchain>
<type>jdk</type>
<provides>
<version>1.8</version>
<vendor>sun</vendor>
</provides>
<configuration>
<jdkHome>/Library/Java/JavaVirtualMachines/jdk1.8.0_25.jdk/Contents/Home</jdkHome>
</configuration>
</toolchain>
<toolchain>
<type>jdk</type>
<provides>
<version>1.7</version>
<vendor>sun</vendor>
</provides>
<configuration>
<jdkHome>/Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home</jdkHome>
</configuration>
</toolchain>
<toolchain>
<type>jdk</type>
<provides>
<version>1.6</version>
<vendor>apple</vendor>
</provides>
<configuration>
<jdkHome>/Library/Java/JavaVirtualMachines/1.6.0_65-b14-462.jdk/Contents/Home</jdkHome>
</configuration>
</toolchain>
<!-- other toolchains -->
<!--
<toolchain>
<type>netbeans</type>
<provides>
<version>5.5</version>
</provides>
<configuration>
<installDir>/path/to/netbeans/5.5</installDir>
</configuration>
</toolchain>
-->
Step 2
Add maven-toolchain-plugin to plugins section in your project pom.xml.
*If using maven 3, ensure this goes into pluginManagement as well *
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-toolchains-plugin</artifactId>
<version>1.1</version>
<executions>
<execution>
<goals>
<goal>toolchain</goal>
</goals>
</execution>
</executions>
<configuration>
<toolchains>
<jdk>
<version>1.7</version>
<vendor>sun</vendor>
</jdk>
</toolchains>
</configuration>
</plugin>
Voila all your other plugins pick up the right JDK. Hope it helps. I spent almost half day on this exact issue today.

Default value for source and target was 1.3 in older versions of maven-compiler plugin (like 2.0.2-6).
Use at least a 3.0 version of the Maven compiler plugin to get this back to the original behaviour, or just configure that plugin to get source and target to appropriate values.

I used following settings to set maven default java compiler version.
first, modify maven settings.xml:
<profile>
<id>jdk-1.8</id>
<activation>
<activeByDefault>true</activeByDefault>
<jdk>1.8</jdk>
</activation>
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion>
</properties>
</profile>
second, in eclipse preferences, make the java home point to jdk home

Suggestion: Use the latest maven compiler plugin.
In order to change the defaults, you should set source and target.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
More Info: maven-compiler-plugin

The simplest solution to such things is using an up-to-date version of Maven (3.1.1) and in particular create a parent pom.xml file for all your projects where you define the configuration and version of your maven-compiler-plugin via pluginManagement or better all of your plugins.

Based on Chinto's answer I got it running on my windows machine with this:
<?xml version="1.0" encoding="UTF8"?>
<toolchains>
<!-- JDK toolchains -->
<toolchain>
<type>jdk</type>
<provides>
<version>1.8</version>
<vendor>openjdk</vendor>
</provides>
<configuration>
<jdkHome>C:\path\to\openJDK1.8.0</jdkHome>
</configuration>
</toolchain>
</toolchains>

NoClassDefFoundError on Maven dependency

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