Swagger 3.0 array's null values

Question

Is it possible to define an array that can not contain null?

I'm compiling it to Java with Open API 3.0

For example for this

A:
  type: array
  minItems: 1
  items:
    $ref: "#/components/schemas/B"
B: 
 type: string
 pattern: ^[a-z]+$

I consider [null] or ["abc",null] invalid

Thanks in advance