<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-antrun-plugin</artifactId>
                <executions>
                    <execution>
                        <id>artifactory-jre</id>
                        <phase>process-resources</phase>
                        <goals>
                            <goal>run</goal>
                        </goals>
                        <configuration>
                            <target>
                                <!-- download file -->
                                <get src="${download.url}/${download.file}${download.filePostfix}"
                                     dest="${project.build.directory}/${download.file}${download.filePostfix}"
                                     verbose="true"
                                     usetimestamp="true"
                                     username="user"
                                     password="password123"/>
                            </target>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

<server>
      <username>user</username>
      <password>password123</password>
      <id>artifactory-jre</id>
    </server>