### Question:
JsonHandler { public static ArrayNode createArrayNode() { return mapper.createArrayNode(); } protected  JsonHandler(); static ObjectNode createObjectNode(); static ArrayNode createArrayNode(); static ObjectNode getFromStringExc(final String value); static ObjectNode getFromString(final String value); static ObjectNode getFromFile(final File file); static T getFromString(final String value, final Class<T> clasz); static Object getFromFile(final File file, final Class<?> clasz); static String writeAsString(final Object object); static String writeAsStringEscaped(final Object object); static String unEscape(final String source); static boolean writeAsFile(final Object object, final File file); static String prettyPrint(final Object object); static String getString(final ObjectNode node, final String field); static String getString(final ObjectNode node, final Enum<?> field); static String getValue(final ObjectNode node, final String field,
                                final String defValue); static Boolean getValue(final ObjectNode node, final String field,
                                 final boolean defValue); static Double getValue(final ObjectNode node, final String field,
                                final double defValue); static Long getValue(final ObjectNode node, final String field,
                              final long defValue); static Integer getValue(final ObjectNode node, final String field,
                                 final int defValue); static byte[] getValue(final ObjectNode node, final String field,
                                final byte[] defValue); static void setValue(final ObjectNode node, final String field,
                              final boolean value); static void setValue(final ObjectNode node, final String field,
                              final double value); static void setValue(final ObjectNode node, final String field,
                              final int value); static void setValue(final ObjectNode node, final String field,
                              final long value); static void setValue(final ObjectNode node, final String field,
                              final String value); static void setValue(final ObjectNode node, final String field,
                              final byte[] value); static boolean exist(final ObjectNode node, final String... field); static String getValue(final ObjectNode node, final Enum<?> field,
                                final String defValue); static Boolean getValue(final ObjectNode node, final Enum<?> field,
                                 final boolean defValue); static Double getValue(final ObjectNode node, final Enum<?> field,
                                final double defValue); static Long getValue(final ObjectNode node, final Enum<?> field,
                              final long defValue); static Integer getValue(final ObjectNode node, final Enum<?> field,
                                 final int defValue); static byte[] getValue(final ObjectNode node, final Enum<?> field,
                                final byte[] defValue); static void setValue(final ObjectNode node, final Enum<?> field,
                              final boolean value); static void setValue(final ObjectNode node, final Enum<?> field,
                              final double value); static void setValue(final ObjectNode node, final Enum<?> field,
                              final int value); static void setValue(final ObjectNode node, final Enum<?> field,
                              final long value); static void setValue(final ObjectNode node, final Enum<?> field,
                              final String value); static void setValue(final ObjectNode node, final Enum<?> field,
                              final byte[] value); static boolean exist(final ObjectNode node, final Enum<?>... field); static Map<String, Object> getMapFromString(final String value); static final ObjectMapper mapper; }### Answer:
@Test public void testCreateArrayNode() { final ArrayNode node = JsonHandler.createArrayNode(); node.add(true); node.add("bytes".getBytes()); node.add(2.0); node.add(3); node.add(5L); node.add("string"); assertEquals(6, node.size()); final String result = JsonHandler.writeAsString(node); ArrayNode node2; try { node2 = (ArrayNode) JsonHandler.mapper.readTree(result); } catch (final JsonProcessingException e) { fail(e.getMessage()); return; } catch (final IOException e) { fail(e.getMessage()); return; } assertEquals(result, JsonHandler.writeAsString(node2)); }