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java - IText edit or remove the layer on PDF

H All,

I am Using IText for adding text layers on PDF. Now i want to edit the existing layers on the PDF, layers are also created by IText only. Seems IText dont have such methods to suppport.

I thought of other way around is remove existing Layer and place new layer on its place. Seems remove also not supported by IText. Any way todo these?

Thanks in adavance.

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As it turned out in comments, the layers in question are what iText indeed calls layers but what actually in PDF lingo is called optional content groups.

There indeed is a utility class for removing such layers in the iText Xtra package (not the extrajars, but itext-xtra.jar): com.itextpdf.text.pdf.ocg.OCGRemover which makes use of the class OCGParser in the same package.

/**
 * Class that knows how to remove OCG layers.
 */
public class OCGRemover
{
    /**
     * Removes layers from a PDF document
     * @param reader    a PdfReader containing a PDF document
     * @param layers    a sequence of names of OCG layers
     * @throws IOException
     */
    public void removeLayers(PdfReader reader, String... layers) throws IOException
    [...]
}

After applying that method to a PdfReader you obviously have to save the changes, e.g. by means of a PdfStamper.


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