### Question:
UtilAll { public static boolean isBlank(String str) { int strLen; if (str == null || (strLen = str.length()) == 0) { return true; } for (int i = 0; i < strLen; i++) { if (Character.isWhitespace(str.charAt(i))) { return true; } } return false; }  static int getPid(); static String offset2FileName(final long offset); static long computeEclipseTimeMilliseconds(final long beginTime); static boolean isItTimeToDo(final String when); static String timeMillisToHumanString(); static String timeMillisToHumanString(final long t); static long computNextMorningTimeMillis(); static String timeMillisToHumanString2(final long t); static String timeMillisToHumanString3(final long t); static double getDiskPartitionSpaceUsedPercent(final String path); static final int crc32(byte[] array); static final int crc32(byte[] array, int offset, int length); static String bytes2string(byte[] src); static byte[] string2bytes(String hexString); static byte[] uncompress(final byte[] src); static byte[] compress(final byte[] src, final int level); static int asInt(String str, int defaultValue); static long asLong(String str, long defaultValue); static String formatDate(Date date, String pattern); static Date parseDate(String date, String pattern); static String responseCode2String(final int code); static String frontStringAtLeast(final String str, final int size); static boolean isBlank(String str); static final String yyyy_MM_dd_HH_mm_ss; static final String yyyy_MM_dd_HH_mm_ss_SSS; static final String yyyyMMddHHmmss; }### Answer:
@Test public void test_isBlank() { { boolean result = UtilAll.isBlank("Hello "); assertTrue(result); } { boolean result = UtilAll.isBlank(" Hello"); assertTrue(result); } { boolean result = UtilAll.isBlank("He llo"); assertTrue(result); } { boolean result = UtilAll.isBlank(" "); assertTrue(result); } { boolean result = UtilAll.isBlank("Hello"); assertTrue(!result); } }