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GWT奇怪的序列化異常

2012-04-28 78 views
3

我有一個應用程序，可以計算9個統計信息存儲在複雜的數據結構中，如HashMap<String, TreeMap<String, Integer>>或者更復雜。每個統計實現接口IStatistic。結果存儲在List<IStatistic>中，其大小（最大的例子）爲3.5MB（我已經手動序列化並將其存入文件）。有時我發送結果給客戶端（通常當數據大小超過1.5MB，即小於某些限制時，異常不會發生）奇怪的異常發生，並且它永遠不會在同一個地方..GWT奇怪的序列化異常

我已閱讀並嘗試每一個類似的解決方案，我發現這裏和在GWT官方頁面，如：

" https://developers.google.com/web-toolkit/doc/latest/tutorial/RPC http://stackoverflow.com/questions/2122798/gwt-occasional-com-google-gwt-user-client-rpc-serializationexception did you check http://code.google.com/webtoolkit/doc/latest/tutorial/RPC.html#serialize the article says: It has a default (zero argument) constructor with any access modifier (e.g. private Foo(){} will work) I'm allways forgetting zeroargument const. when I am making a serializable object :D "

但沒有什麼幫助。也試圖調試它，但它在GWT源中的某處出現故障，我無法看到源代碼。有趣的是，對於較小的數據樣本，一切都很順利。

我正在使用GWT 2.4.0。沒有appengine。

有沒有人有類似的問題，或有一些建議來解決這個問題？

Here are some example exceptions: 
    FIRST EXAMPLE: 
    com.google.gwt.user.client.rpc.IncompatibleRemoteServiceException: The response could not be deserialized 
     at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:221) 
     at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java:287) 
     at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:395) 
     at sun.reflect.GeneratedMethodAccessor52.invoke(Unknown Source) 
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
     at java.lang.reflect.Method.invoke(Unknown Source) 
     at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) 
     at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) 
     at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) 
     at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:337) 
     at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:218) 
     at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136) 
     at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561) 
     at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269) 
     at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91) 
     at com.google.gwt.core.client.impl.Impl.apply(Impl.java) 
     at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:213) 
     at sun.reflect.GeneratedMethodAccessor32.invoke(Unknown Source) 
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
     at java.lang.reflect.Method.invoke(Unknown Source) 
     at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) 
     at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) 
     at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) 
     at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:292) 
     at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:546) 
     at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:363) 
     at java.lang.Thread.run(Unknown Source) 
    Caused by: com.google.gwt.user.client.rpc.SerializationException: 2AS (6) 
     at com.google.gwt.user.client.rpc.impl.SerializerBase.getTypeHandler(SerializerBase.java:153) 
     at com.google.gwt.user.client.rpc.impl.SerializerBase.instantiate(SerializerBase.java:114) 
     at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:111) 
     at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
     at com.google.gwt.user.client.rpc.core.java.util.Map_CustomFieldSerializerBase.deserialize(Map_CustomFieldSerializerBase.java:38) 
     at com.google.gwt.user.client.rpc.core.java.util.TreeMap_CustomFieldSerializer.deserialize(TreeMap_CustomFieldSerializer.java:36) 
     at com.google.gwt.user.client.rpc.core.java.util.TreeMap_FieldSerializer.deserial(TreeMap_FieldSerializer.java:15) 
     at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
     at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
     at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
     at com.google.gwt.user.client.rpc.core.java.util.Map_CustomFieldSerializerBase.deserialize(Map_CustomFieldSerializerBase.java:39) 
     at com.google.gwt.user.client.rpc.core.java.util.HashMap_CustomFieldSerializer.deserialize(HashMap_CustomFieldSerializer.java:34) 
     at com.google.gwt.user.client.rpc.core.java.util.HashMap_FieldSerializer.deserial(HashMap_FieldSerializer.java:19) 
     at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
     at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
     at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
     at hr.fer.zesoi.metals.shared.statistic.result.StatisticM1Result_FieldSerializer.deserialize(StatisticM1Result_FieldSerializer.java:29) 
     at hr.fer.zesoi.metals.shared.statistic.result.StatisticM1Result_FieldSerializer.deserial(StatisticM1Result_FieldSerializer.java:51) 
     at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
     at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
     at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
     at com.google.gwt.user.client.rpc.core.java.util.Collection_CustomFieldSerializerBase.deserialize(Collection_CustomFieldSerializerBase.java:34) 
     at com.google.gwt.user.client.rpc.core.java.util.ArrayList_CustomFieldSerializer.deserialize(ArrayList_CustomFieldSerializer.java:34) 
     at com.google.gwt.user.client.rpc.core.java.util.ArrayList_FieldSerializer.deserial(ArrayList_FieldSerializer.java:19) 
     at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
     at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
     at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
     at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter$ResponseReader$8.read(RequestCallbackAdapter.java:106) 
     at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:214) 
     ... 26 more 



SECOND EXAMPLE: 
com.google.gwt.dev.shell.HostedModeException: Something other than an int was returned from JSNI method '@com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader::readInt()': JS value of type string, expected int 
    at com.google.gwt.dev.shell.JsValueGlue.getIntRange(JsValueGlue.java:266) 
    at com.google.gwt.dev.shell.JsValueGlue.get(JsValueGlue.java:144) 
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeInt(ModuleSpace.java:247) 
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeInt(JavaScriptHost.java:75) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.readInt(ClientSerializationStreamReader.java) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.readString(ClientSerializationStreamReader.java:104) 
    at com.google.gwt.user.client.rpc.core.java.lang.String_CustomFieldSerializer.instantiate(String_CustomFieldSerializer.java:37) 
    at com.google.gwt.user.client.rpc.core.java.lang.String_FieldSerializer.create(String_FieldSerializer.java:11) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.instantiate(SerializerBase.java:115) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:111) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.core.java.util.Collection_CustomFieldSerializerBase.deserialize(Collection_CustomFieldSerializerBase.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.TreeSet_CustomFieldSerializer.deserialize(TreeSet_CustomFieldSerializer.java:36) 
    at com.google.gwt.user.client.rpc.core.java.util.TreeSet_FieldSerializer.deserial(TreeSet_FieldSerializer.java:15) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.core.java.util.Map_CustomFieldSerializerBase.deserialize(Map_CustomFieldSerializerBase.java:39) 
    at com.google.gwt.user.client.rpc.core.java.util.HashMap_CustomFieldSerializer.deserialize(HashMap_CustomFieldSerializer.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.HashMap_FieldSerializer.deserial(HashMap_FieldSerializer.java:19) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at hr.fer.zesoi.metals.shared.statistic.IStatisticResult_FieldSerializer.deserialize(IStatisticResult_FieldSerializer.java:13) 
    at hr.fer.zesoi.metals.shared.statistic.result.StatisticM2Result_FieldSerializer.deserialize(StatisticM2Result_FieldSerializer.java:22) 
    at hr.fer.zesoi.metals.shared.statistic.result.StatisticM2Result_FieldSerializer.deserial(StatisticM2Result_FieldSerializer.java:40) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.core.java.util.Collection_CustomFieldSerializerBase.deserialize(Collection_CustomFieldSerializerBase.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.ArrayList_CustomFieldSerializer.deserialize(ArrayList_CustomFieldSerializer.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.ArrayList_FieldSerializer.deserial(ArrayList_FieldSerializer.java:19) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter$ResponseReader$8.read(RequestCallbackAdapter.java:106) 
    at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:214) 
    at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java:287) 
    at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:395) 
    at sun.reflect.GeneratedMethodAccessor37.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
    at java.lang.reflect.Method.invoke(Unknown Source) 
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) 
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) 
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) 
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:337) 
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:218) 
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136) 
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561) 
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269) 
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91) 
    at com.google.gwt.core.client.impl.Impl.apply(Impl.java) 
    at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:213) 
    at sun.reflect.GeneratedMethodAccessor32.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
    at java.lang.reflect.Method.invoke(Unknown Source) 
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) 
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) 
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) 
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:292) 
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:546) 
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:363) 
    at java.lang.Thread.run(Unknown Source) 


THIRD EXAMPLE: 

    java.lang.NullPointerException 
    at java.util.TreeMap.put(Unknown Source) 
    at java.util.TreeSet.add(Unknown Source) 
    at com.google.gwt.user.client.rpc.core.java.util.Collection_CustomFieldSerializerBase.deserialize(Collection_CustomFieldSerializerBase.java:35) 
    at com.google.gwt.user.client.rpc.core.java.util.TreeSet_CustomFieldSerializer.deserialize(TreeSet_CustomFieldSerializer.java:36) 
    at com.google.gwt.user.client.rpc.core.java.util.TreeSet_FieldSerializer.deserial(TreeSet_FieldSerializer.java:15) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.core.java.util.Map_CustomFieldSerializerBase.deserialize(Map_CustomFieldSerializerBase.java:39) 
    at com.google.gwt.user.client.rpc.core.java.util.HashMap_CustomFieldSerializer.deserialize(HashMap_CustomFieldSerializer.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.HashMap_FieldSerializer.deserial(HashMap_FieldSerializer.java:19) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at hr.fer.zesoi.metals.shared.statistic.IStatisticResult_FieldSerializer.deserialize(IStatisticResult_FieldSerializer.java:13) 
    at hr.fer.zesoi.metals.shared.statistic.result.StatisticM4Result_FieldSerializer.deserialize(StatisticM4Result_FieldSerializer.java:44) 
    at hr.fer.zesoi.metals.shared.statistic.result.StatisticM4Result_FieldSerializer.deserial(StatisticM4Result_FieldSerializer.java:66) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.core.java.util.Collection_CustomFieldSerializerBase.deserialize(Collection_CustomFieldSerializerBase.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.ArrayList_CustomFieldSerializer.deserialize(ArrayList_CustomFieldSerializer.java:34) 
    at com.google.gwt.user.client.rpc.core.java.util.ArrayList_FieldSerializer.deserial(ArrayList_FieldSerializer.java:19) 
    at com.google.gwt.user.client.rpc.impl.SerializerBase.deserialize(SerializerBase.java:95) 
    at com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader.deserialize(ClientSerializationStreamReader.java:113) 
    at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamReader.readObject(AbstractSerializationStreamReader.java:119) 
    at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter$ResponseReader$8.read(RequestCallbackAdapter.java:106) 
    at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:214) 
    at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java:287) 
    at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:395) 
    at sun.reflect.GeneratedMethodAccessor47.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
    at java.lang.reflect.Method.invoke(Unknown Source) 
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) 
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) 
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) 
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:337) 
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:218) 
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136) 
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561) 
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269) 
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91) 
    at com.google.gwt.core.client.impl.Impl.apply(Impl.java) 
    at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:213) 
    at sun.reflect.GeneratedMethodAccessor42.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
    at java.lang.reflect.Method.invoke(Unknown Source) 
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) 
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) 
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) 
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:292) 
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:546) 
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:363) 
    at java.lang.Thread.run(Unknown Source)

來源

2012-04-28 user1362565

回答

2

對於第一個錯誤，這幾乎可以肯定表明你的服務器和客戶端的下跌不同步，以及有什麼可序列化和反序列化有不同的看法。清除瀏覽器緩存，或確保服務器運行與客戶端相同的代碼（如果從谷歌的appengine服務器運行，重新部署到服務器，或者在本地運行時重新啓動）。從字符串「2AS」看起來好像你可能會混淆類型名稱 - 考慮禁用該功能，直到你確實解決這個問題。

二錯誤：

com.google.gwt.dev.shell.HostedModeException: Something other than an int was returned from JSNI method '@com.google.gwt.user.client.rpc.impl.ClientSerializationStreamReader::readInt()': JS value of type string, expected int 
at com.google.gwt.dev.shell.JsValueGlue.getIntRange(JsValueGlue.java:266) 
at com.google.gwt.dev.shell.JsValueGlue.get(JsValueGlue.java:144) 
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeInt(ModuleSpace.java:247) 
at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeInt(JavaScriptHost.java:75)

Fortunatly，這是在Chrome +開發模式的已知問題。它不會在其他瀏覽器中出現，並且在網絡模式下不會發生在Chrome中。使用不同的瀏覽器是避免這種情況的最簡單方法 - 任何運行大量JSNI代碼（例如任何RPC代碼）的代碼最終都會遇到這種情況。

java.lang.NullPointerException 
at java.util.TreeMap.put(Unknown Source) 
at java.util.TreeSet.add(Unknown Source) 
at com.google.gwt.user.client.rpc.core.java.util.Collection_CustomFieldSerializerBase.deserialize(Collection_CustomFieldSerializerBase.java:35) 
at com.google.gwt.user.client.rpc.core.java.util.TreeSet_CustomFieldSerializer.deserialize(TreeSet_CustomFieldSerializer.java:36) 
at com.google.gwt.user.client.rpc.core.java.util.TreeSet_FieldSerializer.deserial(TreeSet_FieldSerializer.java:15)

這是發生在這個代碼：

@SuppressWarnings("unchecked") 
public final class Collection_CustomFieldSerializerBase { 

    public static void deserialize(SerializationStreamReader streamReader, 
     Collection instance) throws SerializationException { 
    int size = streamReader.readInt(); 
    for (int i = 0; i < size; ++i) { 
     Object obj = streamReader.readObject(); 
     instance.add(obj); //line 35 
    } 
    }

這表明obj爲空在該行，那你也許添加一些空對象到TreeSet中（樹形圖中我會內想像）。可能值得在該類中設置一個斷點，以obj爲空來確定是否這是爲什麼，如果是的話，如何定下來。

來源

2012-04-28 20:50:12

+0

非常感謝您對異常的詳細解釋！我已經設法解決我的申請..謝謝！ :)） – user1362565 2012-04-29 09:10:14

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