A dummy FileSystemlProvider

DefaultFileSystem.java

package filesystem_provider;

import java.io.IOException;
import java.nio.file.FileStore;
import java.nio.file.FileSystem;
import java.nio.file.Path;
import java.nio.file.PathMatcher;
import java.nio.file.WatchService;
import java.nio.file.attribute.UserPrincipalLookupService;
import java.nio.file.spi.FileSystemProvider;
import java.util.Objects;
import java.util.Set;

public class DefaultFileSystem extends FileSystem {
  private final FileSystem delegate;
  private final DefaultFileSystemProvider fileSystemProvider;

  DefaultFileSystem(DefaultFileSystemProvider fileSystemProvider,FileSystem delegate) {
    this.fileSystemProvider = Objects.requireNonNull(fileSystemProvider);
    this.delegate = Objects.requireNonNull(delegate);
  }

  @Override
  public FileSystemProvider provider() {
    return fileSystemProvider;
  }
  @Override
  public Path getPath(String first, String... more) {
    return delegate.getPath(first, more);
  }
  @Override
  public void close() throws IOException {
    delegate.close();
  }
  @Override
  public Iterable<FileStore> getFileStores() {
    return delegate.getFileStores();
  }
  @Override
  public PathMatcher getPathMatcher(String syntaxAndPattern) {
    return delegate.getPathMatcher(syntaxAndPattern);
  }
  @Override
  public Iterable<Path> getRootDirectories() {
    return delegate.getRootDirectories();
  }
  @Override
  public String getSeparator() {
    return delegate.getSeparator();
  }
  @Override
  public UserPrincipalLookupService getUserPrincipalLookupService() {
    return delegate.getUserPrincipalLookupService();
  }
  @Override
  public boolean isOpen() {
    return delegate.isOpen();
  }
  @Override
  public boolean isReadOnly() {
    return delegate.isReadOnly();
  }
  @Override
  public WatchService newWatchService() throws IOException {
    return delegate.newWatchService();
  }
  @Override
  public Set<String> supportedFileAttributeViews() {
    return delegate.supportedFileAttributeViews();
  }
}

DefaultFileSystemProvider.java

package filesystem_provider;

import java.io.IOException;
import java.net.URI;
import java.nio.channels.SeekableByteChannel;
import java.nio.file.AccessMode;
import java.nio.file.CopyOption;
import java.nio.file.DirectoryStream;
import java.nio.file.DirectoryStream.Filter;
import java.nio.file.FileStore;
import java.nio.file.FileSystem;
import java.nio.file.LinkOption;
import java.nio.file.OpenOption;
import java.nio.file.Path;
import java.nio.file.attribute.BasicFileAttributes;
import java.nio.file.attribute.FileAttribute;
import java.nio.file.attribute.FileAttributeView;
import java.nio.file.spi.FileSystemProvider;
import java.util.Map;
import java.util.Objects;
import java.util.Set;

public class DefaultFileSystemProvider extends FileSystemProvider {
  private final FileSystemProvider delegate;
  
  public DefaultFileSystemProvider(FileSystemProvider delegate) {
    this.delegate = Objects.requireNonNull(delegate);
  }
  
  @Override
  public Path getPath(URI uri) {
    return delegate.getPath(uri);
  }
  @Override
  public FileSystem getFileSystem(URI uri) {
    return delegate.getFileSystem(uri);
  }
  @Override
  public FileSystem newFileSystem(URI uri, Map<String, ?> env) throws IOException {
    return delegate.newFileSystem(uri, env);
  }  
  @Override
  public void checkAccess(Path path, AccessMode... modes) throws IOException {
    delegate.checkAccess(path, modes);
  }
  @Override
  public void copy(Path source, Path target, CopyOption... options) throws IOException {
    delegate.copy(source, target, options);
  }
  @Override
  public void createDirectory(Path dir, FileAttribute<?>... attrs) throws IOException {
    delegate.createDirectory(dir, attrs);
  }
  @Override
  public void delete(Path path) throws IOException {
    delegate.delete(path);
  }
  @Override
  public <V extends FileAttributeView> V getFileAttributeView(Path path, Class<V> type, LinkOption... options) {
    return delegate.getFileAttributeView(path, type, options);
  }
  @Override
  public FileStore getFileStore(Path path) throws IOException {
    return delegate.getFileStore(path);
  }
  @Override
  public String getScheme() {
    return delegate.getScheme();
  }
  @Override
  public boolean isHidden(Path path) throws IOException {
    return delegate.isHidden(path);
  }
  @Override
  public boolean isSameFile(Path path, Path path2) throws IOException {
    return delegate.isSameFile(path, path2);
  }
  @Override
  public void move(Path source, Path target, CopyOption... options) throws IOException {
    delegate.move(source, target, options);
  }
  @Override
  public SeekableByteChannel newByteChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs) throws IOException {
    return delegate.newByteChannel(path, options, attrs);
  }
  @Override
  public DirectoryStream<Path> newDirectoryStream(Path dir, Filter<? super Path> filter) throws IOException {
    return delegate.newDirectoryStream(dir, filter);
  }
  @Override
  public <A extends BasicFileAttributes> A readAttributes(Path path, Class<A> attributes, LinkOption... options) throws IOException {
    return delegate.readAttributes(path, attributes, options);
  }
  @Override
  public Map<String, Object> readAttributes(Path path, String attributes, LinkOption... options) throws IOException {
    return delegate.readAttributes(path, attributes, options);
  }
  @Override
  public void setAttribute(Path path, String attribute, Object value, LinkOption... options) throws IOException {
    delegate.setAttribute(path, attribute, value, options);
  }
}