@SuppressWarnings("unchecked")
    public E asThis() {
        return (E) this;
    }
Returns this instance typed as the subclass type {@code E}.
<p>
This is the same as the expression:
</p>
<pre>
(B) this
</pre>

@return this instance typed as the subclass type {@code E}.
src/main/java/org/apache/commons/imaging/ImagingParameters.java