test/org/apache/pig/builtin/avro/data/json/recordsWithMaps.json

{"key" : "A",
 "value" : 1,
 "parameters" : {
   "comment" : "first test case"
   }
}
{"key" : "B",
 "value" : 2,
 "parameters" : {
    "comment" : "second map item",
    "also" : "the next item has an empty map"
    }
}
{"key" : "C",
 "value" : 3,
 "parameters" : {}
}