IndexedField annotation in proto file causes java.lang.NumberFormatException

      Start  7: queryTest

7: Test command: /artifacts/jdg-cpp-client-JDG_7.1.1.Final-BOTH/rhel7/build/queryTest
7: Test timeout computed to be: 1500
7: Tests for Query
7: User(id=3,name=Tom,surname=Cat)
7: User(id=4,name=Jerry,surname=Mouse)
7: Tom  Cat
7: Jerry  Mouse
7: terminate called after throwing an instance of 'infinispan::hotrod::HotRodClientException'
7:   what():  java.lang.NumberFormatException: For input string: "_null_"
 7/22 Test  #7: queryTest ........................***Exception: Other  0.27 sec
test 8
      Start  8: queryTest-static

8: Test command: /artifacts/jdg-cpp-client-JDG_7.1.1.Final-BOTH/rhel7/build/queryTest-static
8: Test timeout computed to be: 1500
8: Tests for Query
8: User(id=3,name=Tom,surname=Cat)
8: User(id=4,name=Jerry,surname=Mouse)
8: Tom  Cat
8: Jerry  Mouse
8: terminate called after throwing an instance of 'infinispan::hotrod::HotRodClientException'
8:   what():  java.lang.NumberFormatException: For input string: "_null_"
 8/22 Test  #8: queryTest-static .................***Exception: Other  0.08 sec