iText在现有pdf中合并，缩放和旋转页面

Question

我希望连接现有的pdf，并将它们缩放并旋转到A4纵向页面。今天我用pdfWriter完成了这个：

for (int pageNum = 1; pageNum <= numberOfPages; pageNum++) {
    PdfImportedPage importedPage = writer.getImportedPage( reader, pageNum );
    AffineTransform transform = getAffineTransform(reader, writer, pageNum);
    pdfContentByte.addTemplate(importedPage, transform);
    document.newPage();
}


private AffineTransform getAffineTransform(PdfReader reader, PdfWriter writer, int pageNum) {
    Rectangle readerPageSize = reader.getPageSize( pageNum );
    Rectangle writerPageSize = writer.getPageSize();

    float rPageHeight = readerPageSize.getHeight();
    float rPageWidth = readerPageSize.getWidth();

    float wPageHeight = writerPageSize.getHeight();
    float wPageWidth = writerPageSize.getWidth();

    int pageRotation = reader.getPageRotation( pageNum );

    boolean rotate = (rPageWidth > rPageHeight) && (pageRotation == 0 || pageRotation == 180);
    if(!rotate)
        rotate = ((rPageHeight > rPageWidth) && (pageRotation == 90 || pageRotation ==270));
    //if changing rotation gives us better space rotate an extra 90 degrees.
    if(rotate) pageRotation += 90;
    double randrotate = (double)pageRotation * Math.PI/(double)180;

    AffineTransform transform = new AffineTransform();
    float margin = 0;
    float scale = 1.0f;
    if(pageRotation == 90 || pageRotation == 270 ){
        scale = Math.min((wPageHeight - 2 * margin) / rPageWidth, (wPageWidth- 2 * margin) / rPageHeight);
    } else {
        scale = Math.min(wPageHeight / rPageHeight, wPageWidth / rPageWidth);
    }

    transform.translate((wPageWidth/2) + margin, wPageHeight/2 + margin);
    transform.rotate(-randrotate);
    transform.scale(scale,scale);
    transform.translate(-rPageWidth/2,-rPageHeight/2);
    return transform;
}

这很好用，但删除了图层（OCG）和注释。 是否可以使用图层（OCG）和注释？这用于打印，所以我只需要pdf来显示它，我实际上并不需要图层或注释。