pdf - iText setting Creation Date & Modified Date in sandbox.stamper.SuperImpose.java -

i'm trying set creation date & modified date in superimposing content 1 pdf pdf example sandbox.stamper.superimpose.java.

the principle (i think) clear:

use getinfo() & do

info.put(pdfname.creationdate, new pdfdate(calendar)); 

or

info.put("creationdate", "d:20160508090344+02'00'"); 

depending on whether hashmap<string, string> or pdfdictionary available.

but where? can't quite seem find right place insert code... i'm having trouble overwriting original title attribute.

please take @ following files state.pdf , state_metadata.pdf.

the metadata of former looks this:

the metadata of latter looks this:

you can see title , dates have changed.

now take @ changemetadata example find out how done:

public void manipulatepdf(string src, string dest) throws ioexception, documentexception {     pdfreader reader = new pdfreader(src);     pdfstamper stamper = new pdfstamper(reader, new fileoutputstream(dest));     map info = reader.getinfo();     info.put("title", "new title");     info.put("creationdate", new pdfdate().tostring());     stamper.setmoreinfo(info);     bytearrayoutputstream baos = new bytearrayoutputstream();     xmpwriter xmp = new xmpwriter(baos, info);     xmp.close();     stamper.setxmpmetadata(baos.tobytearray());     stamper.close();     reader.close(); } 

changing title easy:

info.put("title", "new title"); 

changing creation date requires use specific date format, why used pdfdate object:

info.put("creationdate", new pdfdate().tostring()); 

old versions of itext may not allow creation date changed, please make sure you're using recent itext version.

the modification date changed automatically. current date used , can't override this.

the following lines change metadata in info dictionary:

map info = reader.getinfo(); info.put("title", "new title"); info.put("creationdate", new pdfdate().tostring()); stamper.setmoreinfo(info); 

if use old version of adobe reader, see change, more recent pdf viewers give preference metadata stored in xmp metadata stream. means have create new xmp stream:

bytearrayoutputstream baos = new bytearrayoutputstream(); xmpwriter xmp = new xmpwriter(baos, info); xmp.close(); stamper.setxmpmetadata(baos.tobytearray()); 

when you've changed title in info dictionary , don't see change, should try changing xmp metadata too. pdf 2 different sets of metadata contradict each other considered being invalid pdf in cases (e.g. when need meet pdf/a compliance).