### Question:
JP2ProductWriterPlugIn implements ProductWriterPlugIn { @Override public String[] getDefaultFileExtensions() { return JP2Constants.FILE_EXTENSIONS; }  @Override EncodeQualification getEncodeQualification(Product product); @Override Class[] getOutputTypes(); @Override ProductWriter createWriterInstance(); @Override String[] getFormatNames(); @Override String[] getDefaultFileExtensions(); @Override String getDescription(Locale locale); @Override SnapFileFilter getProductFileFilter();  }### Answer:
@Test public void testFileExtensions() { final String[] fileExtensions = plugIn.getDefaultFileExtensions(); assertNotNull(fileExtensions); final List<String> extensionList = Arrays.asList(fileExtensions); assertEquals(2, extensionList.size()); assertEquals(true, extensionList.contains(".jp2")); assertEquals(true, extensionList.contains(".jpeg2000")); }