### Question:
JavaUtils { public static String getClassName(String scriptContent) { int index = scriptContent.indexOf("class"); if (index == -1) { return ""; } char[] chars = scriptContent.toCharArray(); int startIndex = 0; int endIndex = 0; for (int i = index + 5; i < scriptContent.toCharArray().length; i++) { if (startIndex == 0) { if (!isAsciiAlpha(chars[i]) && chars[i] != ' ') { break; } if (isAsciiAlpha(chars[i])) { startIndex = i; endIndex = i; } } else { if (!(isAsciiAlpha(chars[i]) || isDigital(chars[i]))) { endIndex = i; break; } } } return scriptContent.substring(startIndex, endIndex); }  static String getClassName(String scriptContent); static boolean isAsciiAlpha(char ch); static boolean isDigital(char ch);  }### Answer:
@Test public void testGetClassName() { Assert.assertEquals("", JavaUtils.getClassName("")); Assert.assertEquals("", JavaUtils.getClassName("String")); Assert.assertEquals("", JavaUtils.getClassName("classString")); Assert.assertEquals("", JavaUtils.getClassName("class.String")); Assert.assertEquals("String", JavaUtils.getClassName("classString%")); }