import lotus.domino.*;

import java.io.*;
import java.util.*;
import java.lang.*;
import javax.servlet.*;
import javax.servlet.http.*;

/**
 * A servlet example of a method by which 
 * attachments are always downloaded by 
 * the browser
 *
 * Creation date: (4/6/2002 1:25:45 PM)
 * @author: Jon LeDrew
 */
public class GetNotesAttachment extends javax.servlet.http.HttpServlet {
    
/**
 * Process incoming HTTP GET requests
 *
 * @param request Object that encapsulates the request to the servlet
 * @param response Object that encapsulates the response from the servlet
 */
public void doGet(javax.servlet.http.HttpServletRequest request,javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, java.io.IOException {

	ServletOutputStream op;
	InputStream is;
	BufferedInputStream bis;
	String unid;
	String filename;
	String dbpath;

    try {

	//request parameters Notes UNID, Attachment Filename and the Database Path.
        unid        = request.getParameter("unid");
        filename    = request.getParameter("filename");
        dbpath      = request.getParameter("dbpath");

        /***************************************************************
        public boolean getAttachment obviously returns a boolean value
        and sets the private BufferedInputStream bis if the db, doc and attachment are found
        ***************************************************************/
        bis = getAttachment(unid, filename, dbpath);

        if (bis != null) {

            int bytesA = bis.available();
            //the size of the attachment. no. of bytes

            byte [] attachment = new byte[bytesA];
            //create a new byte array specifying the size the same as the size of the attachment

            response.setContentType("application/download");
            response.setContentLength(bytesA);
            response.setHeader("Content-Disposition","attachment;filename=\"" + filename + "\"");
            op = response.getOutputStream();
            //set the response details

            while (true) {
	            int bytesRead = bis.read(attachment, 0, attachment.length);
	            if (bytesRead < 0)
	            	break;
                    op.write(attachment, 0, bytesRead);
	    }
            //read the BufferedInputStream into the byte array
            //write the array to the ServletOutputStream

            //clean up
            bis.close();
            op.flush();
            op.close();
        } else {
	        //Send an error if getAttachment returns false.
	        response.sendError( response.SC_INTERNAL_SERVER_ERROR, 
                    "Could not find the specified attachment - <a href=\"/"
                        + dbpath + "/0/" + unid + "/$file/" + filename + "\">" + filename + "</a>" );

	        /**************************************************************
	        If custom error messages are required.
	        response.setContentType("text/html");
	        pw = response.getWriter();
	        pw.println("Error");
	        **************************************************************/
        }
    
    } catch (IOException e) {
        response.sendError( response.SC_INTERNAL_SERVER_ERROR, 
                    "An IO error ocurred while trying to retrieve file" );
        //e.printStackTrace();
    }
}
/**
 * Insert the method's description here.
 * Creation date: (4/6/2002 1:30:20 PM)
 * @return boolean
 */
public BufferedInputStream getAttachment(String unid, String filename, String dbpath) {

    InputStream is = null;
    BufferedInputStream bis = null;
    NotesThread nThread = new NotesThread();
    //New instance NotesThread

    try {
        nThread.sinitThread();
        Session sess = NotesFactory.createSession();

		/*************************************************************************
		This method creates a Notes Session.  This method uses the local user config if the server is 'local'
		and uses the server permissions if the database is referenced on a server.
		Use Session sess = NotesFactory.createSession((String) null,ID,Password);
		where ID and Password are valid values for a users internet name and password
		*************************************************************************/

        Database dwnldsrvlt = sess.getDatabase(null, dbpath);

        /*************************************************************************
        Set dwnldsrvlt using Session's getDatabase method.  getDatabase(String server, String dbpath)
		null indicates that the session environment is to be used.
        *************************************************************************/

		if (dwnldsrvlt.isOpen()) {
            Document doc = dwnldsrvlt.getDocumentByUNID(unid);
            if (doc != null) {
                EmbeddedObject em = doc.getAttachment(filename);
                if (em != null) {
                    is = em.getInputStream();
                    bis = new BufferedInputStream(is);
                    if (sess != null){
                		sess.recycle();
                	}
                }
            }
        } else {
            dwnldsrvlt.open();
            Document doc = dwnldsrvlt.getDocumentByUNID(unid);
            if (doc != null) {
                EmbeddedObject em = doc.getAttachment(filename);
                if (em != null) {
                    is = em.getInputStream();
                    bis = new BufferedInputStream(is);
                    if (sess != null){
                		sess.recycle();
                	}
                }
            }
        }
    } catch (NotesException ne) {
        /****************************************************************
	Exception caught if the database or document aren't found.
        Returning false executes the finally clause and terminates the NotesThread.
        pw.println(ne.id + " " + ne.text); for custom messages on failure to find the db, doc or
        the attachment.
        ****************************************************************/
	ne.printStackTrace();
            
    } catch (Exception e) {
	e.printStackTrace();
                
    } finally {
        nThread.stermThread();
        //Terminate the thread.
        return bis;
    }
}//end getAttachment
}