Fixed java/spring oneOf generator (Inline oneOf support) #11932

Created by: wagnerrobsan

Fixes #11932 (closed)

When generating a spring or java code with a spec that contains an attribute with an inline oneOf, the code generator creates a code with a bug.

Currently, before the code generation, the DefaultGenerator validates the schema type, if the schema is an object, it calls the default setTypeProperties method in the IJsonSchemaValidationProperties interface to validate the schema. If the schema is an object, the CodegenModel isMap attribute is set to true, which incorrectly creates the code with an additional method for Map structures.

This simple change modifies the Schema type from object to the OneOf interface created to support the provided sub-subschemas.

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