### Question:
SimpleFileIO { @Nonnull public static ESuccess writeFile (@Nonnull final File aFile, @Nonnull final byte [] aContent) { final OutputStream aFOS = FileHelper.getOutputStream (aFile); return aFOS == null ? ESuccess.FAILURE : StreamHelper.writeStream (aFOS, aContent); } private  SimpleFileIO(); @Nullable static byte [] getAllFileBytes(@Nullable final File aFile); @Nullable static byte [] getAllFileBytes(@Nullable final Path aPath); static List <String> readAllLines(@Nonnull final Path aPath, @Nonnull final Charset aCharset); @Nullable static String getFileAsString(@Nullable final File aFile, @Nonnull final Charset aCharset); @Nullable static ICommonsList <String> getAllFileLines(@Nullable final File aFile, @Nonnull final Charset aCharset); static void readFileLines(@Nullable final File aFile, @Nonnull final Charset aCharset, @Nonnull final List <String> aTargetList); static void readFileLines(@Nullable final File aFile,
                                    @Nonnull final Charset aCharset,
                                    @Nonnull final Consumer <? super String> aConsumer); @Nonnull static ESuccess writeFile(@Nonnull final File aFile, @Nonnull final byte [] aContent); @Nonnull static ESuccess writeFile(@Nonnull final File aFile,
                                    @Nonnull final byte [] aContent,
                                    @Nonnegative final int nOffset,
                                    @Nonnegative final int nLength); @Nonnull static ESuccess writeFile(@Nonnull final File aFile, @Nonnull final String sContent, @Nonnull final Charset aCharset);  }### Answer:
@Test public void testWriteFile () { final File aFile = new File ("hahatwf.txt"); try { assertTrue (SimpleFileIO.writeFile (aFile, new byte [10]).isSuccess ()); assertTrue (SimpleFileIO.writeFile (aFile, new byte [10], 0, 5).isSuccess ()); assertTrue (SimpleFileIO.writeFile (aFile, "abc", StandardCharsets.ISO_8859_1).isSuccess ()); } finally { FileOperations.deleteFile (aFile); } try { SimpleFileIO.writeFile (null, new byte [10]); fail (); } catch (final NullPointerException ex) {} try { SimpleFileIO.writeFile (null, new byte [10], 0, 5); fail (); } catch (final NullPointerException ex) {} try { SimpleFileIO.writeFile (null, "abc", StandardCharsets.ISO_8859_1); fail (); } catch (final NullPointerException ex) {} }