final class UtilityClass { private static long someField = System.currentTimeMillis(); static void someMethod() { System.out.println(); new InnerClass(); new InnerStaticClass(); } protected static class InnerClass { private String innerInnerMember; } protected static class InnerStaticClass { private String innerInnerMember; } @java.lang.SuppressWarnings("all") private UtilityClass() { throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated"); } } class UtilityInner { static class InnerInner { static final class InnerInnerInner { static int member; @java.lang.SuppressWarnings("all") private InnerInnerInner() { throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated"); } } } enum UtilityInsideEnum { FOO, BAR; static final class InsideEnum { static int member; @java.lang.SuppressWarnings("all") private InsideEnum() { throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated"); } } } interface UtilityInsideInterface { final class InsideInterface { static int member; @java.lang.SuppressWarnings("all") private InsideInterface() { throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated"); } } } }