Develop Reference

Getting "Skipping JaCoCo execution due to missing execution data file" with Jacoco in VS Code

I'm using Maven 3.8.3, JUnit 5.4.2, and Jacoco 0.8.2, and I am trying to create test coverage reports.
I have a project with unit tests only, but I can't get reports to run, I'm repeatedly getting the error: Skipping JaCoCo execution due to missing execution data file when I run:
mvn clean jacoco:prepare-agent install jacoco:report
Here is how my pom is configured:
<?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.mycompany.app</groupId>
<artifactId>my-app</artifactId>
<version>1.0-SNAPSHOT</version>
<name>my-app</name>
<!-- 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>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>5.4.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>5.4.2</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>0.8.2</version>
<executions>
<execution>
<goals>
<goal>prepare-agent</goal>
</goals>
</execution>
<execution>
<id>report</id>
<phase>prepare-package</phase>
<goals>
<goal>report</goal>
</goals>
</execution>
</executions>
</plugin>
<!-- 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>2.22.0</version>
<configuration>
<forkCount>3</forkCount>
<reuseForks>true</reuseForks>
<argLine>-Xmx1024m -XX:MaxPermSize=256m</argLine>
</configuration>
</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>
</plugins>
</pluginManagement>
</build>
</project>
Any ideas what configuration I'm missing?

Whenever you are providing your custom argLine parameter to maven-surefire-plugin, you need to make sure that the #{argLine} is added to your property. For your xml, it would be like this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<argLine>#{argLine} -Xmx1024m -XX:MaxPermSize=256m</argLine>
</configuration>
</plugin>
Here is a similar question explaining the argLine parameter with Jacoco and Maven Surefire Plugin.

java.lang.NoClassDefFoundError: org/hamcrest/Matchers

I have running JUnit5 testcases w/ Maven 3.
Now I want to use library hamcrest in Java import in Testcase AppTest.java:
import static org.junit.jupiter.api.Assertions.*;
import static org.hamcrest.Matchers.greaterThan;
import static org.hamcrest.Matchers.lessThan;
For Testcase AppTest.java that uses App.java:
double result;
result = app.probability_a_dash(23);
System.out.println("result: "+ result);
assertEquals(lessThan(0.5d), result);
The error on the import is:
java.lang.NoClassDefFoundError: org/hamcrest/Matchers
How do I get hamcrest library properly integrated in maven build:
mvn on the command line integrates hamcrest properly, only IDE intelliJ IDEA is mixing up the imports!
Unfortunately JUnit5 does not detect that 0.0 < 0.5 with hamcrest lessThan: How do I get a passing testcase on this?
My pom.xml is as follows:
<?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.auticon.birthdays</groupId>
<artifactId>CalculateBirthdays</artifactId>
<version>1.0-SNAPSHOT</version>
<name>CalculateBirthdays</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>11</java.version>
<maven.compiler.source>${java.version}</maven.compiler.source>
<maven.compiler.target>${java.version}</maven.compiler.target>
<junit-platform.version>5.6.0</junit-platform.version>
</properties>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>${junit-platform.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>${junit-platform.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest</artifactId>
<version>2.2</version>
<scope>test</scope>
</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>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>com.auticon.birthdays.App</mainClass>
</manifest>
</archive>
</configuration>
</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-failsafe-plugin</artifactId>
<version>2.22.1</version>
<configuration>
<argLine>
--illegal-access=permit
</argLine>
</configuration>
</plugin>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
<configuration>
<filesets>
<fileset>
<directory>${basedir}</directory>
<includes>
<include>**/contacts.xml</include>
<include>**/contacts (1).xml</include>
<include>**/contacts (2).xml</include>
</includes>
<excludes>
<exclude>**/important.log</exclude>
<exclude>**/another-important.log</exclude>
</excludes>
<followSymlinks>false</followSymlinks>
</fileset>
</filesets>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>

I had the same error running my maven project. So, I had to use hancrest-all, a self-contained hamcrest jar containing all of the sub-modules in a single artifact.
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-all</artifactId>
<version>1.3</version>
<scope>test</scope>
</dependency>
Check this link: https://mvnrepository.com/artifact/org.hamcrest/hamcrest-all/1.3

Instead of JUnit5 assertEquals, I had to use in AppTest.java the following hamcrest methods:
import static org.hamcrest.Matchers.*;
import static org.hamcrest.MatcherAssert.assertThat;
and
assertThat(result, lessThan(0.5d));

Creating library jar with dependent jars with maven dependency plugin

I want to create a jar (No main class) which is later used as UDF in apache pig. When i creating the jar with maven the dependent jars are not include inside the output jar.
pom file looks 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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>AppName</artifactId>
<packaging>jar</packaging>
<version>1.0</version>
<name>xzloader-java-pig-udf</name>
<url>http://maven.apache.org</url>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<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>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.1</version>
</dependency>
<dependency>
<groupId>org.apache.pig</groupId>
<artifactId>pig</artifactId>
<classifier>h2</classifier>
<version>0.13.0</version>
</dependency>
</dependencies>
</project>
But the resulted jar always throw
NoClassDefFoundException
when running with apache pig

Here is an extract of my pom.xml which builds a jar with dependencies:
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.1</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> <!-- append to the packaging phase. -->
<goals>
<goal>attached</goal> <!-- goals == mojos -->
</goals>
</execution>
</executions>
</plugin>
The difference I see is the goal: you use single, I use attached.

Maven build is not generating main class files in JAR file-could not find or load main class error

The build was successful without any errors, but I checked the Jar file and there was no class files in it.
I the following command to
$mvn package command
with the following POM.xml :
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.cms.service.utils</groupId>
<artifactId>CMS_Job</artifactId>
<packaging>jar</packaging>
<version>1.0-SNAPSHOT</version>
<name>CMS_Job</name>
<url>http://maven.apache.org</url>
<properties>
<jdk.version>1.7</jdk.version>
<junit.version>4.11</junit.version>
<log4j.version>1.2.17</log4j.version>
<maven-compiler-plugin.version>3.0</maven-compiler-plugin.version>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${log4j.version}</version>
</dependency>
</dependencies>
<build>
<finalName>CMS_Job</finalName>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>${maven-compiler-plugin.version}</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-eclipse-plugin</artifactId>
<version>2.9</version>
<configuration>
<downloadSources>true</downloadSources>
<downloadJavadocs>false</downloadJavadocs>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<includes>
<include>**/log4j.properties</include>
</includes>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>com.cms.service.utils.App</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.5.1</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<!-- exclude junit, we need runtime dependency only -->
<includeScope>runtime</includeScope>
<outputDirectory>${project.build.directory}/dependency-jars/</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
And this is my folder structure is described in the image(Linked)
This is how my jar file contents look like(Check the path on top)
I am new to maven environment.
Please help

Maven jar with dependencies?

I want to build the project so that final jar include all the dependencies in a single jar file
(if not possible includes classes from dependencies in to the jar file)
i followed the thread Including dependencies in a jar with Maven but lt included
the dependencies also which i even did not mention in my pom. Here is my POM which has just two dependencies.
I want when when final is built , it includes it specific dependencies mentioned in pom(either in classes or jar form)
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.myProject</groupId>
<artifactId>utils</artifactId>
<version>1</version>
</dependency>

Here you find an example pom.xml how to solve it with the maven-shade-plugin
When you run mvn package it generates an Jar file target/app-with-dependencies.jar. This Jar file include the compiled classes of the project itself and only the dependencies org.slf4j:slf4j-log4j12 and com.myProject:utils. It does not include the dependencies on which org.slf4j:slf4j-log4j12 depend.
<?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>sub.optimal</groupId>
<artifactId>shadedemo</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<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>
<maven.shade.version>2.3</maven.shade.version>
<maven.antrun.version>1.7</maven.antrun.version>
</properties>
<dependencies>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>com.myProject</groupId>
<artifactId>utils</artifactId>
<version>1</version>
</dependency>
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>${maven.shade.version}</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-shade-plugin</artifactId>
<version>${maven.shade.version}</version>
<configuration>
<quiet>true</quiet>
<verbose>false</verbose>
</configuration>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<finalName>app-with-dependencies</finalName>
<artifactSet>
<includes>
<!--
here you define the dependencies which
you want to be included
-->
<include>org.slf4j:slf4j-log4j12:*</include>
<include>com.myProject:utils:*</include>
</includes>
</artifactSet>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-antrun-plugin</artifactId>
<version>${maven.antrun.version}</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>run</goal>
</goals>
<configuration>
<tasks>
<delete>
<fileset dir="${project.build.directory}" includes="${project.name}-*.jar" />
</delete>
</tasks>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>

One way is to use maven assembly plugin, the pom.xml configuration is like:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>com.taobao.top.appstore.App</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>