GWT strange serialization exception - java

I have application that calculates 9 statistictics that are stored in complex data structures as HashMap<String, TreeMap<String, Integer>> or even more complex. Every statistic implements interface IStatistic. Results are stored in List<IStatistic> and its size (for largest example) is 3.5MB (I have serialized it manually and put it to the file). When I send results to client sometimes (usually when data size goes over 1.5MB, i.e. when is less than some limit exception does not occur) strange exception occurs and it is never in same place..
I have read and tried every similar solution to the problem that I found here and at GWT official page like:
" 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 "
but nothing really helped. Also tried to debug it but it breaks down somewhere in GWT source and I can't see the source. It is interesting that for smaller data samples everything goes smooth.
I am using GWT 2.4.0. without appengine.
Does anyone had similar problem or has some advice to deal with this?
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)

For the first error, this almost certainly indicates that your server and client fell out of sync, and have a different view of what can be serialized and deserialized. Clearing the browser cache, or making sure that the server is running the same code as the client ( by redeploying to the server if running from google's appengine server, or restarting if running locally). From the string "2AS" it looks like you might be obfuscating type names - consider disabling that feature until you get this worked out for sure.
Second error:
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, this is a known issue in Chrome+Dev mode. It will not occur in other browsers, and it will not occur in Chrome in web mode. Using a different browser is the easiest way to avoid this - any code which runs a lot of JSNI code (any RPC code for example) will eventually run into this.
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)
This is occurring in this code:
#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
}
}
This suggests that obj is null at that line, and that you are maybe adding some null object to the TreeSet (within the TreeMap I'd imagine). Might be worth setting a breakpoint in that class, conditional on obj being null to establish if that is why, and if so, how to nail it down.

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at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.pentaho.commons.launcher.Launcher.main(Launcher.java:92)
As you have known by now, the null pointer exception is due to the reason it cannot locate the relevant java libraries. So you must have the paths defined for Java and kettle.

entities cannot be cast to javassist.util.proxy.Proxy

I do have an error trying to get datas into a proxy which should contains its own datas and some others coming from another proxy. ( Many To One Relation )
In my example, product proxy gets its own datas but it seems to be unable to get the Manufacturer proxy.
All i done is to add a getter and a setter in product proxy:
ManufacturerProxy getManufacturer ();
void setManufacturer (ManufacturerProxy manufacturer);
Sounds like something is missing. Can someone help me on this ?
Regards,
pierre
com.google.web.bindery.event.shared.UmbrellaException: Exception caught: Server Error: org.nit.persistance.entites.Manufacturer_$$_javassist_3 cannot be cast to javassist.util.proxy.Proxy
at com.google.web.bindery.requestfactory.shared.impl.AbstractRequestContext$StandardPayloadDialect.processPayload(AbstractRequestContext.java:414)
at com.google.web.bindery.requestfactory.shared.impl.AbstractRequestContext$5.onTransportSuccess(AbstractRequestContext.java:1151)
at com.google.web.bindery.requestfactory.gwt.client.DefaultRequestTransport$1.onResponseReceived(DefaultRequestTransport.java:136)
at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java:258)
at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:412)
at sun.reflect.GeneratedMethodAccessor127.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:338)
at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:219)
at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136)
at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:571)
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:279)
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:242)
at sun.reflect.GeneratedMethodAccessor45.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:293)
at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:547)
at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:364)
at java.lang.Thread.run(Unknown Source)

GWT NoSuchElementException with HTMLPanel and addAndReplaceElement method

Here some explanations.
If my HTML page contains :
<div id="cancel_date">
<h3 id="cancel_date_title"></h3>
<table align="center">
<tr>
<td id="cancel_date_labelDetailService"></td>
<td id="cancel_date_detailService"></td>
</tr>
</table>
</div>
If my code contains
HTMLPanel container = HTMLPanel.wrap(Document.get().getElementById("cancel_date"));
public void init(){
container.add(getMyWidget(), "cancel_date_detailService");
}
public void reload(){
container.addAndReplaceElement(getService(), "cancel_date_detailService");
}
The first time I load my page, I initialize it with the method init(). The second time and after, I call the method reload().
The first time I call the method reload(), everything works fine. But after, I have a NoSuchElementException like this :
ERROR: Uncaught exception escaped
com.google.gwt.event.shared.UmbrellaException: One or more exceptions caught, see full set in UmbrellaException#getCauses
at com.google.gwt.event.shared.EventBus.castFireEvent(EventBus.java:69)
at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:57)
at be.mims.bookme.client.gui.component.MyCellTableFuturDates$7.onSuccess(MyCellTableFuturDates.java:134)
at be.mims.bookme.client.gui.component.MyCellTableFuturDates$7.onSuccess(MyCellTableFuturDates.java:1)
at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:232)
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.GeneratedMethodAccessor88.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
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.GeneratedMethodAccessor79.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
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(Thread.java:722)
Caused by: java.util.NoSuchElementException: cancel_date_detailService
at com.google.gwt.user.client.ui.HTMLPanel.addAndReplaceElement(HTMLPanel.java:224)
at be.mims.bookme.client.gui.FactoryCancelDate.showCancelDate(FactoryCancelDate.java:128)
at be.mims.bookme.client.BookMe.show(BookMe.java:277)
at be.mims.bookme.client.event.StateEvent.dispatch(StateEvent.java:31)
at be.mims.bookme.client.event.StateEvent.dispatch(StateEvent.java:1)
at com.google.gwt.event.shared.GwtEvent.dispatch(GwtEvent.java:1)
at com.google.web.bindery.event.shared.EventBus.dispatchEvent(EventBus.java:40)
at com.google.web.bindery.event.shared.SimpleEventBus.doFire(SimpleEventBus.java:193)
at com.google.web.bindery.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:88)
at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:52)
at com.google.gwt.event.shared.EventBus.castFireEvent(EventBus.java:67)
at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:57)
at be.mims.bookme.client.gui.component.MyCellTableFuturDates$7.onSuccess(MyCellTableFuturDates.java:134)
at be.mims.bookme.client.gui.component.MyCellTableFuturDates$7.onSuccess(MyCellTableFuturDates.java:1)
at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:232)
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.GeneratedMethodAccessor88.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
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.GeneratedMethodAccessor79.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
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(Thread.java:722)
And if I go into the SimpleEventBus class where is the exception:
java.util.NoSuchElementException: cancel_date_detailService
at com.google.gwt.user.client.ui.HTMLPanel.addAndReplaceElement(HTMLPanel.java:224)
at be.mims.bookme.client.gui.FactoryDetailRdv.showDetailsDate(FactoryDetailRdv.java:72)
at be.mims.bookme.client.BookMe.show(BookMe.java:228)
at be.mims.bookme.client.event.StateEvent.dispatch(StateEvent.java:31)
at be.mims.bookme.client.event.StateEvent.dispatch(StateEvent.java:1)
at com.google.gwt.event.shared.GwtEvent.dispatch(GwtEvent.java:1)
at com.google.web.bindery.event.shared.EventBus.dispatchEvent(EventBus.java:40)
at com.google.web.bindery.event.shared.SimpleEventBus.doFire(SimpleEventBus.java:193)
at com.google.web.bindery.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:88)
at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:52)
at com.google.gwt.event.shared.EventBus.castFireEvent(EventBus.java:67)
at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:57)
at be.mims.bookme.client.gui.component.MyCellTableFuturDates$7.onSuccess(MyCellTableFuturDates.java:130)
at be.mims.bookme.client.gui.component.MyCellTableFuturDates$7.onSuccess(MyCellTableFuturDates.java:1)
at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:232)
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.GeneratedMethodAccessor174.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
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.GeneratedMethodAccessor166.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
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(Thread.java:722)
I use GWT 2.4.0
Thanks a lot for help!!!
As its name implies, addAndReplaceElement find the element and replaces it with the given widget. Once you called addAndReplaceElement once for an element, that one element is gone, so the second call obviously won't find it, resulting in the NoSuchElementException you're seeing.
If you ever want to replace your widget with another, then you need to wrap it in an element (i.e. call add instead of addAndReplaceElement), and use remove to remove the previous widget.
Hard to say without a look at your getService() method, but my best guess is that after you call reload() the 1st time the element it's looking for is being replaced. Every other time, the block to be replaced no longer exists, throwing the exception.

Casting problems with Google Maps API

I'm trying to run the following line:
Directions.loadFromWaypoints((Waypoint[])waypoints.toArray(), opts);
But I'm getting:
23:41:44.595 [ERROR] [carathome] Uncaught exception escaped
java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Lcom.google.gwt.maps.client.geocode.Waypoint;
at com.presasystems.gwt.carathome.client.widgets.MostrarLinhasPanel$1$1.onSuccess(MostrarLinhasPanel.java:72)
at com.presasystems.gwt.carathome.client.widgets.MostrarLinhasPanel$1$1.onSuccess(MostrarLinhasPanel.java:1)
at com.google.gwt.user.client.rpc.impl.RequestCallbackAdapter.onResponseReceived(RequestCallbackAdapter.java:216)
at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java:287)
at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:393)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.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:157)
at com.google.gwt.dev.shell.BrowserChannel.reactToMessagesWhileWaitingForReturn(BrowserChannel.java:1713)
at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:165)
at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:120)
at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:507)
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:264)
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:188)
at sun.reflect.GeneratedMethodAccessor9.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:157)
at com.google.gwt.dev.shell.BrowserChannel.reactToMessages(BrowserChannel.java:1668)
at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:401)
at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:222)
at java.lang.Thread.run(Unknown Source)
Why? Shouldn't this cast work? How can I do this in an elegant fashion?
Thanks in advance
Try
Directions.loadFromWaypoints((Waypoint[])(waypoints.toArray()), opts);
Alternatively
Waypoint[] array = new Waypoint[0];
array = waypoints.toArray(array);
Directions.loadFromWaypoints(array, opts);
Or more simply
Waypoint[] array = waypoints.toArray(new Waypoint[0]);
Directions.loadFromWaypoints(array, opts);
See also List#toArray(T[] a).
Addendum: Initially, I thought your cast was a precedence problem. The generic parameter T in List#toArray(T[] a) eliminates the need for an explicit cast by ensuring that the "runtime type of the returned array is that of the specified array." In effect, it "acts as bridge between array-based and collection-based APIs."

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