[CALCITE-4379] Meta.Frame created with java float values in rows hits a ClassCastException in toProto()

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.17.0
• Fix Version/s: avatica-1.18.0
• Component/s: avatica
• Labels: pull-request-available
• Assignee: Dmitri Bourlatchkov
• Reporter: Dmitri Bourlatchkov
• Created: 05/Nov/20 17:25
• Updated: 18/May/21 11:22
• Resolved: 13/Nov/20 21:44

Description

Use case:

• Custom Meta implementation
• Meta.Frame.create(offset, done, rows) is called with a row (a List) containing a java Float value
  • Note: the float value is fetched from Apache Cassandra, which has 32-bit float types (unlike SQL).
  • Related email discussion
• The Frame is serialized by calling its .toProto() method
• ClassCastException occurs

Exception snippet:

java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Float
at org.apache.calcite.avatica.remote.TypedValue.writeToProtoWithType(TypedValue.java:600)
at org.apache.calcite.avatica.remote.TypedValue.toProto(TypedValue.java:805)
at org.apache.calcite.avatica.Meta$Frame.serializeScalar(Meta.java:991)
at org.apache.calcite.avatica.Meta$Frame.parseColumn(Meta.java:977)
at org.apache.calcite.avatica.Meta$Frame.toProto(Meta.java:942)
at org.apache.calcite.avatica.remote.Service$FetchResponse.serialize(Service.java:1468)
[...snip...]