map集合遍历的两种方式，在spring中的依赖注入

/**     * map集合注入     */        @Test        public void testBookMAP(){            ApplicationContext ac=new ClassPathXmlApplicationContext("spring.xml");            Book book=ac.getBean("book", Book.class);            Map<Integer, Book> mapBooks = book.getNameMap();            Set<Integer> keySet = mapBooks.keySet();            //迭代器遍历            /*Iterator<Integer> iterator = keySet.iterator();            while (iterator.hasNext()) {                Integer key=iterator.next();                Book book2 = mapBooks.get(key);                System.out.println(book2.getName());            }*/        //增强for遍历            for(Integer i:keySet){                Integer key=(Integer)i;                System.out.println(key+"--"+mapBooks.get(key).getName());            }    }