### Question:
DockerPluginUtils { public static boolean isBlank(String str) { int strLen; if (str != null && (strLen = str.length()) != 0) { for (int i = 0; i < strLen; ++i) { if (!Character.isWhitespace(str.charAt(i))) { return false; } } return true; } else { return true; } }  static void printError(String msg); static List<BLangRecordLiteral.BLangRecordKeyValueField> getKeyValuePairs(BLangRecordLiteral bLangRecordLiteral); static void printDebug(String msg); static boolean isBlank(String str); static void deleteDirectory(Path pathToBeDeleted); static String resolveValue(String value); static AnnotationAttachmentNode createAnnotation(String annotationName);  }### Answer:
@Test public void isBlankTest() { Assert.assertTrue(DockerPluginUtils.isBlank("")); Assert.assertTrue(DockerPluginUtils.isBlank(" ")); Assert.assertTrue(DockerPluginUtils.isBlank(null)); Assert.assertFalse(DockerPluginUtils.isBlank("value")); }