FileUpload

====== Dateien auf den Server hochladen ======
FIXME IE sendet kompletten Pfad...

===== Voraussetzungen =====
http://commons.apache.org/fileupload/ \\ 
http://commons.apache.org/io/

===== Formular zum Hochladen =====
<code java>
import java.io.PrintWriter;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
public class FileUpload extends HttpServlet {
 
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            out.println("<html>");
            out.println("<head>");
            out.println("<title>FileUpload</title>");
            out.println("</head>");
            out.println("<form enctype=\"multipart/form-data\" method=\"POST\" action=\"SaveData\">");
            out.println("<table>");
            for (int i = 0; i < 5; i++) {
                out.println("<tr>");
                out.println("<td>File " + (i + 1) + ": </td>");
                out.println("<td><input type=\"file\" name=\"file" + i + "\"></td>");
                out.println("</tr>");
            }
            out.println("</table>");
            out.println("</form");
            out.println("</html>");
        } finally {
            out.close();
        }
    }
 
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }
 
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }
 
    @Override
    public String getServletInfo() {
        return "Short description";
    }
}
</code>

===== Verarbeitung am Server =====
<code java>
import java.io.IOException;
import java.io.PrintWriter;
import java.io.File;
import java.util.Iterator;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.tomcat.util.http.fileupload.FileItem;
import org.apache.tomcat.util.http.fileupload.FileUploadException;
import org.apache.tomcat.util.http.fileupload.disk.DiskFileItemFactory;
import org.apache.tomcat.util.http.fileupload.servlet.ServletFileUpload;

public class SaveData extends HttpServlet {

    private String filePath = "data/";
    private File file;
    final private int maxSize = 10000000;      // 10 MB
    final private int maxThreshold = 1000000;  // 1 MB

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException, FileUploadException, Exception {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            File dir = new File(filePath);
            if (!dir.exists()) {
                dir.mkdirs();
            }
            DiskFileItemFactory factory = new DiskFileItemFactory();
            factory.setSizeThreshold(maxThreshold);
            factory.setRepository(new File("."));
            ServletFileUpload upload = new ServletFileUpload(factory);
            upload.setSizeMax(maxSize);
            List fileItems = upload.parseRequest(request);
            Iterator it = fileItems.iterator();
            while (it.hasNext()) {
                FileItem fi = (FileItem) it.next();
                if (!fi.isFormField()) {
                    file = new File(filePath + fi.getName());
                    fi.write(file);
                }
            }
        } finally {
            out.close();
        }
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (FileUploadException ex) {
            Logger.getLogger(CsvReceiver.class.getName()).log(Level.SEVERE, null, ex);
        } catch (Exception ex) {
            Logger.getLogger(CsvReceiver.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (FileUploadException ex) {
            Logger.getLogger(CsvReceiver.class.getName()).log(Level.SEVERE, null, ex);
        } catch (Exception ex) {
            Logger.getLogger(CsvReceiver.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    @Override
    public String getServletInfo() {
        return "Short description";
    }
}
</code>