title: spring data mongodb enum mapping converter
body: <p>I would like code not throws exception when java code load enum value from mongo that not exists in enum code </p>
  
  <p>Exemple : </p>
  
  <pre><code>java.lang.IllegalArgumentException: No enum constant fr.myapp.type.OrderOptionEnum.TELEPHONE
  at java.lang.Enum.valueOf(Enum.java:238)
  at org.springframework.data.mongodb.core.convert.MappingMongoConverter.getPotentiallyConvertedSimpleRead(MappingMongoConverter.java:819)
  at org.springframework.data.mongodb.core.convert.MappingMongoConverter.readCollectionOrArray(MappingMongoConverter.java:909)
  at org.springframework.data.mongodb.core.convert.MappingMongoConverter.readValue(MappingMongoConverter.java:1184)
  </code></pre>
  
  <p>Because TELEPHONE not existe in OrderOptionEnum</p>
  
  <p>I juste want the code return null value</p>
  
  <p>Any idea ?</p>
  
  <p>Regards</p>