// to delete on exit
            }
        } else if (metadataFile.exists()) {
            try (InputStream input = Files.newInputStream(metadataFile.toPath())) {
                metadata = new Metadata(new MetadataStaxReader().read(input, false));
            }
        }

        boolean changed;

                    syncContext.acquire(null, Collections.singleton(metadata));

                    if (metadata.getPath() != null && Files.exists(metadata.getPath())) {
                        try (InputStream in = Files.newInputStream(metadata.getPath())) {
                            versioning = new Versioning(
                                    new MetadataStaxReader().read(in, false).getVersioning());
                        }

                    syncContext.acquire(null, Collections.singleton(metadata));

                    if (metadata.getPath() != null && Files.exists(metadata.getPath())) {
                        try (InputStream in = Files.newInputStream(metadata.getPath())) {
                            versioning = new Versioning(
                                    new MetadataStaxReader().read(in, false).getVersioning());

                            /*

            } catch (MalformedURLException e) {
                throw new IllegalStateException(e);
            }
        } else {
            return Files.newInputStream(new File(pluginFile, descriptor).toPath());
        }
    }

    /**
     * Creates a shallow copy of this plugin descriptor.
     */
    @Override
    public PluginDescriptor clone() {

    }

    /*
     * TODO share with DefaultPluginMappingManager.
     */
    protected Metadata readMetadata(File mappingFile) throws RepositoryMetadataReadException {

        try (InputStream in = Files.newInputStream(mappingFile.toPath())) {
            return new Metadata(new MetadataStaxReader().read(in, false));
        } catch (FileNotFoundException e) {

        try {
            if (extensionsFile != null && Files.exists(extensionsFile)) {
                try (InputStream is = Files.newInputStream(extensionsFile)) {
                    return validateCoreExtensionsDescriptorFromFile(
                            extensionsFile,
                            List.copyOf(new CoreExtensionsStaxReader()

                if (pluginXml.isFile()) {
                    pluginDescriptor = parsePluginDescriptor(
                            () -> Files.newInputStream(pluginXml.toPath()), plugin, pluginXml.getAbsolutePath());
                }
            }

            if (pluginDescriptor == null) {

        this.location = location;
        this.substitute = substitute;
    }

    public void load(Path location) throws IOException {
        try (InputStream is = Files.newInputStream(location)) {
            load(is);
        }
    }

    public void load(URL location) throws IOException {
        try (InputStream is = location.openStream()) {
            load(is);
        }

        this.location = location;
        this.substitute = substitute;
    }

    public void load(Path location) throws IOException {
        try (InputStream is = Files.newInputStream(location)) {
            load(is);
        }
    }

    public void load(URL location) throws IOException {
        try (InputStream is = location.openStream()) {
            load(is);
        }

        if (extensionsFile != null) {
            Path extensionsPath = Path.of(extensionsFile);
            if (Files.exists(extensionsPath)) {
                try (InputStream is = Files.newInputStream(extensionsPath)) {
                    return new CoreExtensionsStaxReader()
                            .read(is, true, InputSource.of(extensionsFile))
                            .getExtensions();
                }