reading MANIFEST.MF file from jar file using JAVA

Achieve the attributes in this simple way

    public static String  getMainClasFromJarFile(String jarFilePath) throws Exception{
    // Path example: "C:\\Users\\GIGABYTE\\.m2\\repository\\domolin\\DeviceTest\\1.0-SNAPSHOT\\DeviceTest-1.0-SNAPSHOT.jar";
    JarInputStream jarStream = new JarInputStream(new FileInputStream(jarFilePath));
    Manifest mf = jarStream.getManifest();
    Attributes attributes = mf.getMainAttributes();
    // Manifest-Version: 1.0
    // Built-By: GIGABYTE
    // Created-By: Apache Maven 3.0.5
    // Build-Jdk: 1.8.0_144
    // Main-Class: domolin.devicetest.DeviceTest
    String mainClass = attributes.getValue("Main-Class");
    //String mainClass = attributes.getValue("Created-By");
    //  Output: domolin.devicetest.DeviceTest
    return mainClass;
}

1. read version;
2. we copied MANIFEST.MF from jar to user home.

    public void processManifestFile() {
        String version = this.getClass().getPackage().getImplementationVersion();
        LOG.info("Version: {}", version);
        Path targetFile = Paths.get(System.getProperty("user.home"), "my-project", "MANIFEST.MF");

        try {
            URL url = this.getClass().getProtectionDomain().getCodeSource().getLocation();
            JarFile jarFile = new JarFile(url.getFile());
            Manifest manifest = jarFile.getManifest();
            try(FileWriter fw = new FileWriter(targetFile.toFile())) {
                manifest.getMainAttributes().entrySet().stream().forEach( x -> {
                    try {
                        fw.write(x.getKey() + ": " + x.getValue() + "\n");
                        LOG.info("{}: {}", x.getKey(), x.getValue());
                    } catch (IOException e) {
                        LOG.error("error in write manifest, {}", e.getMessage());
                    }
                });
            }
            LOG.info("Copy MANIFEST.MF to {}", targetFile);
        } catch (Exception e) {
            LOG.error("Error in processing MANIFEST.MF file", e);
        }
    }