Spring @ Autowired 개인 속성 주석 (set 방법 없 음)

오늘 은 POJO 클래스 의 개인 속성 이 @ Autowired 를 통 해 자동 으로 주입 되 는 것 을 보 았 습 니 다.
예전 에 이해 한 의존 주입 에 따라 주입 점 이 필요 합 니 다. set 방법 일 수도 있 고 구조 방법 일 수도 있 습 니 다. 그러나 이 속성 은 외부 access 를 통 해 주입 할 수 있 는 방법 이 없습니다. 그 는 어떻게 주입 합 니까?
인터넷 에서 한 번 검색 해 보 니 답 은 다음 과 같다.
stackoverflow.com/questions/4127365/how-can-spring-hibernate-access-private-members/4127403#4127403
You can set private a variable of another object through reflection. Here is an example on how to do it. Consider the following object with a private variable:
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3 public   class   MyBean {      private   String   message; }
Normally the message field wouldn't be accessible from outside MyBean, however, SnoopyClass can set and get its value. I wrote two static methods:  setValue  which can set a value into a private field called fieldName of an Object bean and a  getValue  method which can get the value of a private variable called fieldName from an Object bean.
The main method just demonstrates its use by creating an Object of MyBean class, setting the message variable and retrieving it. I've actually tested this code as a standalone application and it works.
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24 import   java.lang.reflect.Field; public   class   SnoopyClass {      private   static   void   setValue( Object   bean,  String   fieldName,  Object   value)              throws IllegalArgumentException, IllegalAccessException,              SecurityException, NoSuchFieldException {          Field privateVar = bean.getClass().getDeclaredField(fieldName);          privateVar.setAccessible( true );          privateVar. set (bean, value);      }      private   static   Object   getValue( Object   bean,  String   fieldName)              throws IllegalArgumentException, IllegalAccessException,              SecurityException, NoSuchFieldException {          Field privateVar = bean.getClass().getDeclaredField(fieldName);          privateVar.setAccessible( true );          return   privateVar. get (bean);      }      public   static   void   main( String [] argv)              throws IllegalArgumentException, SecurityException,              IllegalAccessException, NoSuchFieldException {           MyBean instance =  new   MyBean();           setValue(instance,  "message" ,  "Shht! Don't tell anyone!" );           System.out.println( "The message is '"   + getValue(instance,  "message" ));      } }
The implementation uses  getDeclaredField  method on the class of the Object, because this method can look for all fields, even private. In contrast,  getField  can only access public members. The next step is calling  setAccessible  on the field to allow reading and writing it. The last step, is simply use the  get  and  set  methods provided by the  java.lang.reflect.Field  class.
This kind of manipulation is allowed only if the security manager allows that. By default Java doesn't install any security manager, so in a standalone program that you launch through your IDE or the command line, you won't have any problems to use this technique. I've also tried, in a Spring Application under Tomcat, and it's still working.
The primary application, at least for me, is being able to set private variables in my unit tests, especially for Spring Beans, without polluting the interface with unneeded setters.