step by step generate war file in angular 8 code example

Example: angular.json to war

<properties>
    <angular.project.location>angular-project</angular.project.location>
    <angular.project.nodeinstallation>node_installation</angular.project.nodeinstallation>
</properties>

 <plugin>
            <groupId>com.github.eirslett</groupId>
            <artifactId>frontend-maven-plugin</artifactId>
            <version>1.0</version>
            <configuration>
                <workingDirectory>${angular.project.location}</workingDirectory>
                <installDirectory>${angular.project.nodeinstallation}</installDirectory>
            </configuration>
            <executions>
                <!-- It will install nodejs and npm -->
                <execution>
                    <id>install node and npm</id>
                    <goals>
                        <goal>install-node-and-npm</goal>
                    </goals>
                    <configuration>
                        <nodeVersion>v6.10.0</nodeVersion>
                        <npmVersion>3.10.10</npmVersion>
                    </configuration>
                </execution>

                <!-- It will execute command "npm install" inside "/e2e-angular2" directory -->
                <execution>
                    <id>npm install</id>
                    <goals>
                        <goal>npm</goal>
                    </goals>
                    <configuration>
                        <arguments>install</arguments>
                    </configuration>
                </execution>
                <!-- It will execute command "npm build" inside "/e2e-angular2" directory 
                    to clean and create "/dist" directory -->
                <execution>
                    <id>npm build</id>
                    <goals>
                        <goal>npm</goal>
                    </goals>
                    <configuration>
                        <arguments>run build</arguments>
                    </configuration>
                </execution>
            </executions>
        </plugin>

        <!-- Plugin to copy the content of /angular/dist/ directory to output 
            directory (ie/ /target/transactionManager-1.0/) -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-resources-plugin</artifactId>
            <version>2.4.2</version>
            <executions>
                <execution>
                    <id>default-copy-resources</id>
                    <phase>process-resources</phase>
                    <goals>
                        <goal>copy-resources</goal>
                    </goals>
                    <configuration>
                        <overwrite>true</overwrite>
                        <!-- This folder is the folder where your angular files 
                        will be copied to. It must match the resulting war-file name.
                        So if you have customized the name of war-file for ex. as "app.war"
                        then below value should be ${project.build.directory}/app/ 
                        Value given below is as per default war-file name -->
                        <outputDirectory>${project.build.directory}/${project.artifactId}-${project.version}/</outputDirectory>
                        <resources>
                            <resource>
                                <directory>${project.basedir}/${angular.project.location}/dist</directory>
                            </resource>
                        </resources>
                    </configuration>
                </execution>
            </executions>
        </plugin>