public JBIG2Page(int page,
    JBIG2SegmentReader sr) 
{
			this.page = page;
			this.sr = sr;
}

 public  void addSegment(JBIG2Segment s) 
{
			segs.put(new Integer(s.segmentNumber), s);
}

 public byte[] getData(boolean for_embedding) throws IOException 
{
			ByteArrayOutputStream os = new ByteArrayOutputStream();
			for (Iterator i = segs.keySet().iterator(); i.hasNext();  ) {
				Integer sn = (Integer) i.next();
				JBIG2Segment s = (JBIG2Segment) segs.get(sn);
				// pdf reference 1.4, section 3.3.6 JBIG2Decode Filter
				// D.3 Embedded organisation
				if ( for_embedding && 
						( s.type == END_OF_FILE || s.type == END_OF_PAGE ) ) {
					continue;
				}
				if ( for_embedding ) {
					// change the page association to page 1
					byte[] headerData_emb = copyByteArray(s.headerData);
					if ( s.page_association_size ) {
						headerData_emb[s.page_association_offset] = 0x0;
						headerData_emb[s.page_association_offset+1] = 0x0;
						headerData_emb[s.page_association_offset+2] = 0x0;
						headerData_emb[s.page_association_offset+3] = 0x1;
					} else {
						headerData_emb[s.page_association_offset] = 0x1;
					}
					os.write(headerData_emb);
				} else {
					os.write(s.headerData);
				}
				os.write(s.data);
			}
			os.close();
			return os.toByteArray();
}

return as a single byte array the header-data for each segment in segment number order, EMBEDDED organization, but i am putting the needed segments in SEQUENTIAL organization. if for_embedding, skip the segment types that are known to be not for acrobat.