### Question:
IntrospectUtil { public static boolean isCollectionType(Class<?> typeClazz) { if (typeClazz == null || typeClazz.isPrimitive()) { return false; } boolean isCollectionType = false; for (Class<?> collectionClazz : s_collectionTypes) { if (collectionClazz.isAssignableFrom(typeClazz)) { isCollectionType = true; break; } } return isCollectionType; }  static Class<?> getWrapperType(String primitiveType); static JTypeTable initializeJType(String fullyQualifiedClassName); static JTypeTable initializeAsyncInterfaceJType(String fullyQualifiedClassName); static void addAllTypesReferred(Class<?> type, Set<String> typeNameSet); static boolean hasAttachmentTypeRef(Class<?> type, Set<String> typeNameSet); static boolean isParameterizedType(Type type); static boolean isWildCardType(Type type); static boolean isGenericArrayType(Type type); static Method getMethodWithSignature(
				Class<?> clazz, 
				String methodName, 
				Class<?>[] params); static boolean hasCollectionType(Class<?>[] types); static boolean isCollectionType(Class<?> typeClazz); static Class<?> loadClass(String fullyQualifiedClassName); static Method[] getPublicInstanceMethods(Class<?> clazz); static Method[] getMatchedMethods(Class<?> clazz, Set<String> methodNameSet); static boolean isPublicInstanceMethod(Method method); static List<Method> getMethods(Class<?> clazz);  }### Answer:
@Test public void isCollectionTypeString() throws Exception { Assert.assertFalse(IntrospectUtil.isCollectionType(String.class)); }
@Test public void isCollectionTypeList() throws Exception { Assert.assertTrue(IntrospectUtil.isCollectionType(List.class)); }
@Test public void isCollectionTypeInteger() throws Exception { Assert.assertFalse(IntrospectUtil.isCollectionType(Integer.TYPE .getClass())); }
@Test public void isCollectionTypeHashtable() throws Exception { Assert.assertTrue(IntrospectUtil.isCollectionType(Hashtable.class)); }
@Test public void isCollectionTypeNull() throws Exception { Class<?> typeClass = null; Assert.assertFalse(IntrospectUtil.isCollectionType(typeClass)); }