### Question:
NameUtil { public static boolean isJavaIdentifier(String s) { if (s.length() == 0) { return false; } if (JavaUtils.isJavaKeyword(s)) { return false; } if (!Character.isJavaIdentifierStart(s.charAt(0))) { return false; } for (int i = 1; i < s.length(); i++) { if (!Character.isJavaIdentifierPart(s.charAt(i))) { return false; } } return true; } private  NameUtil(); static List<String> toWordList(String s); static List<String> toWordList(String s, boolean allowUnderscore); static void escape(StringBuilder sb, String s, int start); static boolean isJavaIdentifier(String s); static String mangleNameToClassName(String name); static String mangleNameToClassName(String name, boolean allowUnderscores); static String mangleNameToVariableName(String name);  }### Answer:
@Test public void testIsJavaIdentifier() { assertFalse(NameUtil.isJavaIdentifier("int")); }