code: public static <T extends Transform> T multiply (AffineTransform a, AffineTransform b, T into) {
          return multiply(a.m00, a.m01, a.m10, a.m11, a.tx, a.ty,
                          b.m00, b.m01, b.m10, b.m11, b.tx, b.ty, into);
      }
docs: Multiplies the supplied two affine transforms, storing the result in {@code into}. {@code
  into} may refer to the same instance as {@code a} or {@code b}.
  @return {@code into} for chaining.