There is a problem when a bean has both getX() and hasX() or isX() methods and XML constraint mappings are used.

Example:

The test above throws an exception:

However, the code may work perfectly if the bean has only one property.

This happens because GetterPropertySelectionStrategy.getGetterMethodNameCandidates() returns Set<String> and org.hibernate.validator.internal.util.privilegedactions.GetMethodFromGetterNameCandidates#run iterates through Set, which does not provide any ordering guarantees.

The solution, probably, is using List instead of Set here.

There is PR with test which may help reproduce the issue and possible solution: