[CALCITE-2677] Struct types with one field are not mapped correctly to Java Classes

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.17.0
• Fix Version/s: 1.19.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Stamatis Zampetakis
• Reporter: Stamatis Zampetakis
• Created: 16/Nov/18 13:51
• Updated: 25/Mar/19 00:11
• Resolved: 10/Mar/19 23:57

Description

There are various places in the code where given a RelDataType we need to obtain the respective Java Class/Type. This is done mainly through JavaTypeFactory#getJavaClass. For the Calcite runtime it passes through PhysType#fieldClass and PhysType#getJavaFieldType. 

However, when the RelDataType is a struct of one field the returned Class/Type is not the correct one since the struct type is simplified to the type of its component. 

Issue Links

• is related to: CALCITE-2776 Wrong value when accessing struct types with one attribute
• links to: GitHub Pull Request #923