[BUG] [JAVA] Inheritance: required param of child not correct

Description

If child defines a parameter as required but parent does not have it as required, it generates a new parameter for the child (name shadowing).

openapi-generator version

6.0.1 (using java)

Generation Details & Steps to reproduce

e.g. with a yaml similar to this:

parent:
  properties:
    param:
      type: string

child:
  allOf:
    $ref: 'parent'
    type: object
    required:
      param

Then the child class has its own attribute 'param' and does not inherit from parent (neither the attribute nor its getter and setter). Hence inheritance is not done properly.

Expected Behavior

I expect the child class to inherit the 'param' and its setter and getter from the parent.

Suggest a fix

I think the 'pojo.mustache' need the {{isInherited}} to call super in those cases.

Start by reproducing the issue with the YAML example and inspect the Java generator's pojo.mustache template, particularly the isInherited handling. Done means the child reuses the parent's param attribute, getter, and setter instead of generating shadowing members.