Hi, Am 29.04.2011 22:00, schrieb Hiller, Dean (Contractor): > > Proof is below. The main summary is that DateTimeFieldType.java has NO > hashCode method so returns different hashcodes in different JVMs > L…..and AbstractPartialDate’s hashCode calls that hashCode which > varies from JVM to JVM so two dates that are equal become unequal. It > works in a single JVM since there is only one instance of > DateTimeFieldType in a JVM. >
This behaviour is okay according to my understanding of the general contract of hashCode() [1]: "(...) Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application (...)" In other words: it's okay to return different hashCodes when the same code runs inside different JVMs (which would be _different_ executions of the same application). If you want to compare value objects for equality, use equals(). The hashCode method has a significantly different contract. [1]: http://download.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html#hashCode%28%29 Best regards Ansgar > First bug I hit in joda time after using it for about 2 years(still > way better than the jdk time api ;) ). > > I have the following code to log what the LocalDate(or rather > AbstractPartialDate) is doing in it’s hashCode method > > It turns out the hashcode of the dt.getFieldType(i)(year, monthOfYear > and date are all different) returns different values on the different > servers!!!! Ouch!!!! > > This email is html color coded from eclipse copy so not sure if you > can read it???….. > > /log/.info("Resolver: saving rdbms key="+ overallKey > > + " hash1="+ pk.getAccountId().hashCode() + " hash2=" > > + pk.getMarketvalueDt().hashCode()); > > LocalDate dt = pk.getMarketvalueDt(); > > *for*(*int*i = 0; i < dt.size(); i++) { > > *int*val = dt.getValue(i); > > *int*typeHash = dt.getFieldType(i).hashCode(); > > /log/.info("type="+ dt.getFieldType(i) + " hashVal="+ val > > + " hashType="+ typeHash); > > } > > /log/.info("hash="+ dt.getChronology().hashCode()); > > Log from server 1…. > > 2011-04-29 13:41:53,209 INFO [Function Execution Processor1] > c.b.p.p.KeyMappingR > > esolution > > : Resolver: saving rdbms key=RdbmsKey > [rdbmsClass=com.broadridge.papr.olddb.marketvalue.ETLMvAccountDbo, > rdbmsKey=MvAccountPK [accountId=18487, marketvalueDt=2011-01-12]] > hash1=18487 hash2=-77876543 > > 2011-04-29 13:41:53,209 INFO [Function Execution Processor1] > c.b.p.p.KeyMappingResolution > > : type=year hashVal=2011 hashType=20028211 > > 2011-04-29 13:41:53,209 INFO [Function Execution Processor1] > c.b.p.p.KeyMappingResolution > > : type=monthOfYear hashVal=1 hashType=1235672037 > > 2011-04-29 13:41:53,209 INFO [Function Execution Processor1] > c.b.p.p.KeyMappingResolution > > : type=dayOfMonth hashVal=12 hashType=1773059369 > > 2011-04-29 13:41:53,209 INFO [Function Execution Processor1] > c.b.p.p.KeyMappingResolution > > : hash=885211 > > Log from server 2 > > 2011-04-29 13:41:53,210 INFO [PartitionedRegion Message Processor1] > c.b.p.p.KeyMappingResolution > > : Resolver: saving rdbms key=RdbmsKey > [rdbmsClass=com.broadridge.papr.olddb.marketvalue.ETLMvAccountDbo, > rdbmsKey=MvAccountPK [accountId=18487, marketvalueDt=2011-01-12]] > hash1=18487 hash2=-1292312838 > > 2011-04-29 13:41:53,210 INFO [PartitionedRegion Message Processor1] > c.b.p.p.KeyMappingResolution > > : type=year hashVal=2011 hashType=1905251818 > > 2011-04-29 13:41:53,210 INFO [PartitionedRegion Message Processor1] > c.b.p.p.KeyMappingResolution > > : type=monthOfYear hashVal=1 hashType=438644709 > > 2011-04-29 13:41:53,210 INFO [PartitionedRegion Message Processor1] > c.b.p.p.KeyMappingResolution > > : type=dayOfMonth hashVal=12 hashType=2137747659 > > 2011-04-29 13:41:53,210 INFO [PartitionedRegion Message Processor1] > c.b.p.p.KeyMappingResolution > > : hash=885211 > > *From:*Hiller, Dean (Contractor) > *Sent:* Friday, April 29, 2011 1:32 PM > *To:* 'joda-interest@lists.sourceforge.net' > *Subject:* hashCode on LocalDate failed in this instance > > We are using a nosql platform in which we shipped a LocalDate to > another server. The hashCode of LocalDate on the other server was > different than the one on my local server. I am still not why. The > toString spit out the exact same date AND on my local server when I > serialize/deserialize, the hashCode was still the same. It was only > when I serialized the LocalDate to another server and called hashcode > that I received a different result even though the toString is the > exact same date on both nodes. > > Is LocalDate grabbing some different timezone from the local computer > instead of serializing and sending that date. All of this comes from > simple new LocalDate().plusOrMinusXXX(int x) calls. We don’t use any > timezone stuff at this point though. > > Thanks, > > Dean > > This message and any attachments are intended only for the use of the > addressee and > may contain information that is privileged and confidential. If the reader of > the > message is not the intended recipient or an authorized representative of the > intended recipient, you are hereby notified that any dissemination of this > communication is strictly prohibited. If you have received this communication > in > error, please notify us immediately by e-mail and delete the message and any > attachments from your system. > > > > ------------------------------------------------------------------------------ > WhatsUp Gold - Download Free Network Management Software > The most intuitive, comprehensive, and cost-effective network > management toolset available today. Delivers lowest initial > acquisition cost and overall TCO of any competing solution. > http://p.sf.net/sfu/whatsupgold-sd > > > _______________________________________________ > Joda-interest mailing list > Joda-interest@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/joda-interest ------------------------------------------------------------------------------ WhatsUp Gold - Download Free Network Management Software The most intuitive, comprehensive, and cost-effective network management toolset available today. Delivers lowest initial acquisition cost and overall TCO of any competing solution. http://p.sf.net/sfu/whatsupgold-sd _______________________________________________ Joda-interest mailing list Joda-interest@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/joda-interest
