DataHelperImpl.toDate was report a NullPointerException

[Li...@Foresee.com.cn]

Hi All , 
      when I  read the data from a table , there is a Datetime field in the
table ,
if the datetime field'value is null , the SDO will produce a
NullPointException ,
Maybe this is a bug , and How to fixed it  ? 
 
Exception content as follow : 
 
12:02:21,015 [main] ERROR [DasService] 
java.lang.NullPointerException
 at
org.apache.tuscany.sdo.helper.DataHelperImpl.toDate(DataHelperImpl.java:48)
 at
org.apache.tuscany.sdo.model.impl.ModelFactoryImpl.createDateFromString(Mode
lFactoryImpl.java:1931)
 at
org.apache.tuscany.sdo.model.impl.ModelFactoryImpl.createFromString(ModelFac
toryImpl.java:224)
 at
org.apache.tuscany.sdo.impl.FactoryBase$SDOEFactoryImpl.createFromString(Fac
toryBase.java:270)
 at
org.eclipse.emf.ecore.util.EcoreUtil.createFromString(EcoreUtil.java:2982)
 at
org.eclipse.emf.ecore.change.impl.FeatureChangeImpl.getValue(FeatureChangeIm
pl.java:428)
 at
org.apache.tuscany.sdo.impl.ChangeSummarySettingImpl.getValue(ChangeSummaryS
ettingImpl.java:89)
 at
org.apache.tuscany.das.rdb.util.DataObjectUtil.restoreAttributeValues(DataOb
jectUtil.java:74)
 at
org.apache.tuscany.das.rdb.util.DataObjectUtil.getRestoredCopy(DataObjectUti
l.java:41)
 at
org.apache.tuscany.das.rdb.impl.DeleteOperation.<init>(DeleteOperation.java:
34)
 at
org.apache.tuscany.das.rdb.impl.ChangeFactory.createDeleteOperation(ChangeFa
ctory.java:77)
 at
org.apache.tuscany.das.rdb.impl.ChangeSummarizer.createChange(ChangeSummariz
er.java:103)
 at
org.apache.tuscany.das.rdb.impl.ChangeSummarizer.loadChanges(ChangeSummarize
r.java:80)
 at
org.apache.tuscany.das.rdb.impl.ApplyChangesCommandImpl.execute(ApplyChanges
CommandImpl.java:64)
 at org.apache.tuscany.das.rdb.impl.DASImpl.applyChanges(DASImpl.java:310)
 
 
 
Best Regards ,
 
 
Li Taojian