方法引发了'java.lang.IllegalArgumentException'异常。如何使用java反射设置私有最终值

Question

 @Test
    void partitionProcessorTest() throws Exception {
     
        EventData eventData = new EventData(body);
        
        //  below line code for finding nested class
        Class<?> []clazz = eventData.getClass().getDeclaredClasses();

        // and this is my inner class object 
        Class<?> inner = clazz[0];

        // this is my inner class constructer 
        Constructor<?> constructor = inner.getDeclaredConstructor();
        constructor.setAccessible(true);
        Object obj = constructor.newInstance();

        // this is my sequenceNumber field. which is private final Long type, in inner class 
        Field f = inner.getDeclaredField("sequenceNumber");
        f.setAccessible(true);

        //I am trying to remove final keyword from declared field in my inner class
        Field filed= Field.class.getDeclaredField("modifiers");
        filed.setAccessible(true);
        filed.setInt(f, f.getModifiers() & ~Modifier.FINAL);
       
        // but iam getting exception, where i am donig mistake please suggest me  
        // In this line i am getting exception --> f.setLong(eventData , 10l);
        try{
        f.setLong(eventData , 10l);
        }
        catch(Throwable e)
        {
        e.printStackTrace();
        }
        System.out.println(obj);
    }

com.azure.messaging.eventhubs.models.eventcontext.updateCheckPoint(eventcontext.java:101)com.tdchannels.sdk.ms.channel.services.eventhubconsumerthread.lambda$new$0(eventhubconsumerthread.java:106)com.tdchannels.sdk.ms.channel.services.impl.eventhubconsumerthread.partitionprocessortest(eventhubconsumerserviceimplest.java:99)

Answer 1

无法将java.lang.long字段com.azure.messaging.eventHubs.EventData$SystemProperties.SequenceNumber设置为（long）10

根据跟踪，您正在将long原语设置为long object，请尝试将对象设置为long而不是long

像这样

Long aLong = Long.valueOf(100);
try{
    f.setLong(eventData , aLong);
}
catch(Throwable e)
{
    e.printStackTrace();
}