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>org.toy</groupId>
	<artifactId>demo</artifactId>
	<version>1.0.0-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>demo</name>

	<dependencies>

		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.13</version>
			<scope>test</scope>
		</dependency>

	</dependencies>

	<build>
		<plugins>

			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.8.1</version>
			</plugin>

			<plugin>
				<artifactId>maven-assembly-plugin</artifactId>
				<version>3.2.0</version>
				<configuration>
					<descriptorRefs>
						<descriptorRef>jar-with-dependencies</descriptorRef>
					</descriptorRefs>
					<finalName>demo</finalName>
					<appendAssemblyId>false</appendAssemblyId>
					<archive>
						<manifest>
							<mainClass>org.toy.demo.Calculator</mainClass>
						</manifest>
					</archive>
				</configuration>
				<executions>
					<execution>
						<id>build-jar-with-dependencies</id>
						<phase>package</phase>
						<goals>
							<goal>single</goal>
						</goals>
					</execution>
				</executions>
			</plugin>

		</plugins>
	</build>
</project>