HtmlFileViewer extends HdfsFileViewer { @Override public ContentType getContentType() { return ContentType.HTML; } HtmlFileViewer(); @Override String getName(); @Override Set<Capability> getCapabilities(final FileSystem fs, final Path path); @Override void displayFile(final FileSystem fs, final Path path, final OutputStream outputStream,
      final int startLine, final int endLine); @Override ContentType getContentType();  }
@Test public void testContentType() { assertEquals(ContentType.HTML, this.viewer.getContentType()); }