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我正在使用方法

   static void setFinalStatic(Field field, Object newValue) throws Exception
   {
      field.setAccessible(true);

      final Field modifiersField = Field.class.getDeclaredField("modifiers");
      modifiersField.setAccessible(true);
      modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);

      field.set(null, newValue);
   }  

用于更改private static final字段。
但是如果字段有类型Map我会得到异常

Exception in thread "main" java.lang.IllegalAccessException: Can not set static final java.util.Map field org.hibernate.type.TypeFactory.BASIC_TYPES to java.util.HashMap
    at sun.reflect.UnsafeFieldAccessorImpl.throwFinalFieldIllegalAccessException(UnsafeFieldAccessorImpl.java:55)
    at sun.reflect.UnsafeFieldAccessorImpl.throwFinalFieldIllegalAccessException(UnsafeFieldAccessorImpl.java:59)
    at sun.reflect.UnsafeQualifiedStaticObjectFieldAccessorImpl.set(UnsafeQualifiedStaticObjectFieldAccessorImpl.java:59)
    at java.lang.reflect.Field.set(Field.java:657)
    at com.company.tester.Main.setFinalStatic(Main.java:64)  

有任何想法吗?

更多代码

  Field types = TypeFactory.class.getDeclaredField("BASIC_TYPES");
  types.setAccessible(true);
  Map val = (Map) types.get(null);
  Map newMap = new HashMap(val);
  newMap.put(String.class.getName(), new MyType());
  setFinalStatic(TypeFactory.class.getDeclaredField("BASIC_TYPES"), new HashMap());
4

1 回答 1

3

field.setAccessible(true)轮流对该字段的所有安全检查。更改其明显的修饰符将无济于事。还有其他一些东西阻止了它的工作。

我不会尝试替换地图,而是尝试更新它。

Field types = TypeFactory.class.getDeclaredField("BASIC_TYPES");
types.setAccessible(true);
Object bt = types.get(null);
Field m = bt.getClass().getDeclaredField("m");
m.setAccessible(true);
Map val = (Map) m.get(bt);
val.put(String.class.getName(), new MyType());
于 2012-08-08T12:44:49.160 回答