JPA Attribute Converter ignored in Criteria Query Where Clause

When using a JPA Attribute Converter which converts numeric basic types in a WHERE Clause in a Criteria Query, the Attribute Converter is not used when the supplied numeric literal is negative.

A little background to the issue: X509 certificate serial numbers represented as Java BigIntegers should be persisted as uppercase Hex Strings in a VARCHAR Table Column. To convert between BigIntegers and Strings, a JPA Attribute Adapter is used. Everything works fine, except for one thing: When using the converted BigInteger field to query the database using the Criteria API, the serial number is not converted and the database returns an error because the type does not match (ORA-01722: invalid number). This only happens when the literal used in the WHEN clause is negative though. Positive literals work fine.

The issue seems to be related to how the AST is built for the resulting HQL Query, since a negative integer literal is split into separate AST Nodes. A UnaryArithmeticNode does not implement the ExpectedTypeAwareNode Interface, which results in the BinaryLogicOperatorNode not applying the Property Adapter to the right hand side of the equals expression. The literal is therefore not converted into the correct type.

HQL AST for the failing query:

A sample project showcasing the issue is located over at GitHub.