Configure hash code calculation

[Peter Fouquet]

Hi,
I want attributes that are not set (null values) not to be change the hashCode.
For this, I want to set the magic value in the hashCode calculation from 43 to 0, for example
result = (result*PRIME) + (this.name == null ? 0 : this.name.hashCode());

Is it possible to configure the primeForNull in HandlerUtil.java
public static int primeForNull() {
return 43;
}

Thanks for any suggestions
Peter