자바 반사 기술 총화

@Test
public void test() throws ClassNotFoundException {
    //    ：   .class
    Class<Book> bookClass = Book.class;
    //    ：   .getClass()
    Class<? extends Book> aClass = new Book().getClass();
    //    ：        Class  
    Class<?> aClass1 = Class.forName("com.demo07.Book");
}

@Test
public void test3() throws Exception {
    //   class  
    Class<?> aClass = Class.forName("com.demo07.Book");
    //       
    Constructor<?> constructor = aClass.getDeclaredConstructor(String.class, Double.class);
    //   java      
    constructor.setAccessible(true);
    //     
    Book book = (Book) constructor.newInstance("    ", 45.0);
    System.out.println(book.toString());

    //         public     
    Field[] fields = aClass.getFields();
    //            
    Field[] declaredFields = aClass.getDeclaredFields();
    //             public     
    Method[] methods = aClass.getMethods();
    //          
    Method[] declaredMethods = aClass.getDeclaredMethods();
    //       
    Method setBookName = aClass.getDeclaredMethod("setBookName", String.class);
    setBookName.setAccessible(true);
    //     ：     ：    ，  
    setBookName.invoke(book, "    ");
    Method getBookName = aClass.getDeclaredMethod("getBookName");
    getBookName.setAccessible(true);
    System.out.println(getBookName.invoke(book));

    //         
    Table table = (Table) aClass.getAnnotation(Table.class);
    System.out.println(table.value());
    Field bookName = aClass.getDeclaredField("bookName");
    //           
    Colnum colnum = bookName.getAnnotation(Colnum.class);
    System.out.println(colnum.name());
    System.out.println(colnum.type());
    System.out.println(colnum.lenght());
}