Java反射-访问保护字段

您可能会遇到两个问题-字段可能无法正常访问（私有），并且不在您正在查看的类中，而是位于层次结构中的某个位置。

这样的事情甚至可以解决这些问题：

public class SomeExample {  public static void main(String[] args) throws Exception{    Object myObj = new SomeDerivedClass(1234);    Class myClass = myObj.getClass();    Field myField = getField(myClass, "value");    myField.setAccessible(true); //required if field is not normally accessible    System.out.println("value: " + myField.get(myObj));  }  private static Field getField(Class clazz, String fieldName)        throws NoSuchFieldException {    try {      return clazz.getDeclaredField(fieldName);    } catch (NoSuchFieldException e) {      Class superClass = clazz.getSuperclass();      if (superClass == null) {        throw e;      } else {        return getField(superClass, fieldName);      }    }  }}class SomebaseClass {  private Integer value;  SomebaseClass(Integer value) {    this.value = value;  }}class SomeDerivedClass extends SomebaseClass {  SomeDerivedClass(Integer value) {    super(value);  }}