如何找到Java類中的哪個對象不能被序列化？

Question

我的應用程序出現以下錯誤：

WARNING: Cannot serialize session attribute org.ajax4jsf.application.AjaxStateHolder for session 27420D80AE859865FCD27E869C330659
java.io.NotSerializableException: com.his.op.patreg.web.RegistrationForm$5
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
    at java.util.HashMap.writeObject(HashMap.java:1129)
    at sun.reflect.GeneratedMethodAccessor165.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1495)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
    at java.util.HashMap.writeObject(HashMap.java:1129)
    at sun.reflect.GeneratedMethodAccessor165.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1495)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547)
    at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:440)
    at org.ajax4jsf.application.AjaxStateHolder.writeObject(AjaxStateHolder.java:197)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1495)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
    at org.apache.catalina.session.StandardSession.writeObject(StandardSession.java:1700)
    at org.apache.catalina.session.StandardSession.writeObjectData(StandardSession.java:1092)
    at org.apache.catalina.session.FileStore.save(FileStore.java:341)
    at org.apache.catalina.valves.PersistentValve.invoke(PersistentValve.java:187)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1137)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

堆棧跟蹤沒有提供有關哪個對象無法序列化的任何有用信息。 有什么好的方法可以找到問題孩子嗎？ 我的類太大並且包含很多屬性，並且該屬性包含其他幾個屬性，因此很難找出哪個屬性不可序列化。

Answer 1

堆棧跟蹤的這一部分：

java.io.NotSerializableException: com.his.op.patreg.web.RegistrationForm$5

是不可序列化的類。 RegistrationForm$5表示它是在com.his.op.patreg.web.RegistrationForm中實例化的匿名類。

Answer 2

查找com.his.op.patreg.web.RegistrationForm$5 （在目標目錄中名為RegistrationForm$5.class ）並在將反編譯它的 IDE 中打開它。

內容應該會提示您它是RegistrationForm中的哪個匿名類。 然后使該類實現Serializable 。

Answer 3

-Dsun.io.serialization.extendedDebugInfo=true傳遞給 JVM。

例如：在startup.bat中添加SET CATALINA_OPTS=%CATALINA_OPTS% -Dsun.io.serialization.extendedDebugInfo=true