code: public void setRtfDocument(RtfDocument doc) {
          this.document = doc;
          if(headerAll != null) {
              headerAll.setRtfDocument(this.document);
          }
          if(headerFirst != null) {
              headerFirst.setRtfDocument(this.document);
          }
          if(headerLeft != null) {
              headerLeft.setRtfDocument(this.document);
          }
          if(headerRight != null) {
              headerRight.setRtfDocument(this.document);
          }
      }
docs: Sets the RtfDocument this RtfElement belongs to
  
  @param doc The RtfDocument to use