### Question:
ClassUtil { public static Object newInstance(final String javaClassName) { final Class<?> javaClass = classForName(javaClassName); return newInstance(javaClass); } private  ClassUtil(); static Object newInstance(final String javaClassName); static J newInstance(final String javaClassName, final Class<J> type); static J newInstance(final Class<J> clazz); static J newInstance(final Constructor<J> constructor, final Object[] args); static Constructor<J> findConstructor(final Class<J> clazz, final Class<?>[] parameterTypes); static Class<?> classForName(final String javaClassName); static Class<? extends J> classForName(final String javaClassName, final Class<J> type); static Object invoke(final Object instance, final Method method, final Object... args); static void set(final Object instance, final Field field, final Object value); static Object get(final Object instance, final Field field); static Method findMethod(final Class<?> clazz, final String methodName, final Class<?>... parameterTypes); static Collection<Field> getAllFields(final Class<?> clazz, final Class<? extends Annotation> annotation); static Collection<Method> getAllMethods(final Class<?> clazz, final Class<? extends Annotation> annotation); static Collection<Field> getAllFields(final Class<?> clazz); static Collection<Method> getAllMethods(final Class<?> clazz); static Set<Class<?>> getAllInterfaces(final Class<?> clazz); static Class<?> getGeneric(final Constructor<?> constructor, final int i); static Class<?> getGeneric(final Method method, final int i); static Class<?> getGeneric(final Field field); static Class<?> getGeneric(
			final Type type,
			final Supplier<RuntimeException> exceptionSupplier); static String getPropertyName(final Method method);  }### Answer:
@Test public void testNewInstance() { final String className = StringBuilder.class.getCanonicalName(); final Object created = ClassUtil.newInstance(className); assertEquals(StringBuilder.class, created.getClass()); }
@Test public void testNewInstanceWithType() { final String className = StringBuilder.class.getCanonicalName(); final StringBuilder created = ClassUtil.newInstance(className, StringBuilder.class); nop(created); assertEquals(StringBuilder.class, created.getClass()); }
@Test public void testNewInstanceWithTypeError() { assertThrows(Exception.class, () -> { final String className = StringBuilder.class.getCanonicalName() + "."; final StringBuilder created = ClassUtil.newInstance(className, StringBuilder.class); nop(created); }); }
@Test public void testNewInstanceWithClasss() { final Object created = ClassUtil.newInstance(StringBuilder.class); assertEquals(StringBuilder.class, created.getClass()); }
@Test public void testNewInstanceAbstract() { assertThrows(Exception.class, () -> { final String className = SAbstractD.class.getCanonicalName(); final Object created = ClassUtil.newInstance(className); nop(created); }); }
@Test public void testNewInstanceException() { assertThrows(Exception.class, () -> { final String className = SD.class.getCanonicalName(); final Object created = ClassUtil.newInstance(className); nop(created); }); }
@Test public void testNewInstanceFail() { assertThrows(Exception.class, () -> { final String className = StringBuilder.class.getCanonicalName() + "."; final Object created = ClassUtil.newInstance(className); nop(created); }); }