Unexpected error executing a simple map reduce operation

[jfcorugedo]

I want to use fongo (1.5.10 and 1.6.6) to test a very simple map reduce operation of my application.

During the execution of the map reduce, fongo trhows an unexpected error:

java.lang.RuntimeException: json can't serialize type : class org.mozilla.javascript.gen.c1 at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:77) at com.mongodb.util.JSONSerializers$MapSerializer.serialize(JSONSerializers.java:317) at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:79) at com.mongodb.util.JSONSerializers$IterableSerializer.serialize(JSONSerializers.java:290) at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:79) at com.mongodb.util.JSONSerializers$MapSerializer.serialize(JSONSerializers.java:317) at com.mongodb.util.ClassMapBasedObjectSerializer.serialize(ClassMapBasedObjectSerializer.java:79) at com.mongodb.util.JSON.serialize(JSON.java:54) at com.mongodb.util.JSON.serialize(JSON.java:40) at com.mongodb.BasicDBObject.toString(BasicDBObject.java:97) at java.lang.String.valueOf(String.java:2981) at java.lang.StringBuilder.append(StringBuilder.java:131) at com.mongodb.FongoDBCollection.insert(FongoDBCollection.java:114) at com.mongodb.DBCollection.insert(DBCollection.java:161) ...

The problem is in this line (FongoDBCollection.java:114):

  DBObject cloned = filterLists(Util.cloneIdFirst(encodeDecode(obj, encoder)));
  if (LOG.isDebugEnabled()) {
       LOG.debug("insert: " + cloned);
  }

When Logger tries to obtain a String representation of cloned object, it throws a RuntimeException.

If I turn off DEBUG traces of that class (<logger name="com.mongodb" level="INFO"/>) then everything works.

Can you take a look?

Thanks!

[twillouer]

Hi,

can you try against the master branch ?

I don't know exactly your set of test, can you provide me a simple case ?

[jfcorugedo]

Ok, I've tested your change and now it doesn't fail, but it doesn't print the content of the object either.

This line:

LOG.debug("insert:  {}", cloned);

Outputs this trace:

2016-03-08 12:37:47,141 [DEBUG] [main] com.mongodb.FongoDBCollection - insert:  [FAILED toString()]