話不多說,直接上代碼。
//創建對象
User user = new User();
//使用反射機制創建對象
Class<?> forName = Class.forName("com.User");
//默認使用無參構造對象
//User classUser = (User)forName.newInstance();
//System.out.println(classUser);
//創建有參的構造函數
Constructor<?> userHasArgs = forName.getConstructor(String.class,String.class);
User userNew = (User)userHasArgs.newInstance("20","李四");
System.out.println(userNew.toString());
Class<?> forName = Class.forName("com.User");
//獲取類的所有的屬性名稱
Field[] declaredFields = forName.getDeclaredFields();
for (Field field : declaredFields) {
System.out.println(field.getName());
}
//獲取所有的方法名稱
Method[] methods = forName.getMethods();
for (Method method : methods) {
System.out.println(method.getName());
}
User user = (User)forName.newInstance();
Field id = forName.getDeclaredField("id");
id.setAccessible(true);
id.set(user, "20");
Field name = forName.getDeclaredField("name");
name.setAccessible(true);
name.set(user, "張三");
System.out.println(user);
常用知識點:
//禁止Java的反射機制
//將對應的構造參數以及無參構造方法去掉就可以禁用或者改爲私有的