vaadin-framework/client/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>com.vaadin</groupId>
        <artifactId>vaadin-root</artifactId>
        <version>8.15-SNAPSHOT</version>
    </parent>
    <!-- Needed by a plugin in release build -->
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-client</artifactId>
    <name>vaadin-client</name>
    <packaging>jar</packaging>

    <url>https://vaadin.com/</url>
    <description>Vaadin client</description>

    <dependencies>
        <!-- LIBRARY DEPENDENCIES (compile time) -->
        <!-- Project modules -->
        <dependency>
            <groupId>${project.groupId}</groupId>
            <artifactId>vaadin-shared</artifactId>
            <version>${project.version}</version>
        </dependency>

        <dependency>
            <groupId>${project.groupId}</groupId>
            <artifactId>vaadin-server</artifactId>
            <version>${project.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>${project.groupId}</groupId>
                    <artifactId>vaadin-sass-compiler</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <!-- Needed GWT dependencies, includes gwt-user -->
        <dependency>
            <groupId>com.google.gwt</groupId>
            <artifactId>gwt-elemental</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-resources-plugin</artifactId>
                <executions>
                    <!-- Copy .java files to package -->
                    <execution>
                        <id>copy-sources</id>
                        <!-- here the phase you need -->
                        <phase>process-resources</phase>
                        <goals>
                            <goal>copy-resources</goal>
                        </goals>
                        <configuration>
                            <outputDirectory>${project.build.outputDirectory}</outputDirectory>
                            <resources>
                                <resource>
                                    <directory>src/main/resources</directory>
                                    <filtering>false</filtering>
                                </resource>
                                <resource>
                                    <directory>src/main/java</directory>
                                    <filtering>false</filtering>
                                </resource>
                            </resources>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

            <plugin>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-bundle-plugin</artifactId>
                <extensions>true</extensions>
                <configuration>
                    <instructions>
                        <Bundle-RequiredExecutionEnvironment>${osgi.execution.environment}</Bundle-RequiredExecutionEnvironment>
                        <Export-Package>com.vaadin.*;version="${osgi.bundle.version}"</Export-Package>
                        <Import-Package></Import-Package>
                    </instructions>
                </configuration>
                <executions>
                    <execution>
                        <id>bundle-manifest</id>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>manifest</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
                        <index>false</index>
                        <manifest>
                            <addDefaultImplementationEntries>true</addDefaultImplementationEntries>
                        </manifest>
                        <manifestEntries>
                            <Vaadin-Package-Version>1</Vaadin-Package-Version>
                            <Vaadin-Widgetsets>com.vaadin.DefaultWidgetSet</Vaadin-Widgetsets>
                        </manifestEntries>
                    </archive>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-checkstyle-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>checkstyle</goal>
                        </goals>
                        <phase>process-sources</phase>
                    </execution>
                </executions>
            </plugin>

            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>animal-sniffer-maven-plugin</artifactId>
                <configuration>
                    <skip>true</skip>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>