如题 二楼上代码
java.io.NotSerializableException: com.client.Ac01
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1081)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:302)
at java.util.ArrayList.writeObject(ArrayList.java:569)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:917)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1339)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1290)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1079)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:302)
at com.client.Client.inokeServlet(Client.java:22)
at com.client.Client.testAc01(Client.java:76)
at com.client.Client.main(Client.java:92)
Exception in thread "main" java.lang.NullPointerException
at com.client.Client.main(Client.java:94)

求大神帮忙

ObjectOutputStream dataout = new ObjectOutputStream(con.getOutputStream());
dataout.writeObject(listObj);
dataout.flush();
dataout.close();
调用writeObject()出现异常

没人吗？ 好吧....跪了....