DrawableWriterFilter extends FileFilter { @Override public boolean accept(File f) { if (f == null) { return false; } if (f.isDirectory()) { return true; } String ext = getExtension(f).toLowerCase(); for (String extension : capabilities.getExtensions()) { if (extension.equals(ext)) { return true; } } return false; } DrawableWriterFilter(IOCapabilities capabilities); @Override boolean accept(File f); @Override String getDescription(); IOCapabilities getWriterCapabilities();  }
@Test public void testAccept() { assertFalse(filter.accept(null)); }