private float[] popFloatArray() throws PDFParseException {
        Object obj = stack.pop();
        if (!(obj instanceof Object[])) {
            throw new PDFParseException("Expected an [array] here.");
        }
        Object[] source = (Object[]) obj;
        float[] ary = new float[source.length];
        for (int i = 0; i < ary.length; i++) {
            if (source[i] instanceof Double) {
                ary[i] = ((Double) source[i]).floatValue();
            } else {
                throw new PDFParseException("This array doesn't consist only of floats.");
            }
        }
        return ary;
    }