org.polymap.core.workbench.dnd.DndUploadServlet.java Source code

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Here is the source code for org.polymap.core.workbench.dnd.DndUploadServlet.java

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/*                                                                                           
 * polymap.org                                                                               
 * Copyright 2012, Polymap GmbH, and individual contributors as indicated                    
 * by the @authors tag.                                                                      
 *                                                                                           
 * This is free software; you can redistribute it and/or modify it                           
 * under the terms of the GNU Lesser General Public License as                               
 * published by the Free Software Foundation; either version 3 of                            
 * the License, or (at your option) any later version.                                       
 *                                                                                           
 * This software is distributed in the hope that it will be useful,                          
 * but WITHOUT ANY WARRANTY; without even the implied warranty of                            
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU                          
 * Lesser General Public License for more details.                                           
 */
package org.polymap.core.workbench.dnd;

import java.util.ArrayList;
import java.util.List;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.io.IOUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.ListMultimap;

/**
 * This servlet handles DnD upload requests.
 *
 * @author <a href="http://www.polymap.de">Falko Braeutigam</a>
 * @since 3.1
 */
public class DndUploadServlet extends HttpServlet {

    private static final Log log = LogFactory.getLog(DndUploadServlet.class);

    private static final String CONTEXT_TEMP_DIR = "javax.servlet.context.tempdir";

    private static DndUploadServlet instance = null;

    public static DndUploadServlet instance() {
        assert instance != null;
        return instance;
    }

    public static File getUploadTempDir(final HttpSession session) {
        ServletContext context = session.getServletContext();
        StringBuffer path = new StringBuffer();
        File tempDir = (File) context.getAttribute(CONTEXT_TEMP_DIR);
        File result = new File(tempDir.getAbsolutePath(), session.getId());
        if (!result.exists()) {
            result.mkdir();
        }
        return result;
    }

    // instance *******************************************

    private ListMultimap<String, DesktopDropEvent> uploads = ArrayListMultimap.create();

    public DndUploadServlet() throws Exception {
        assert instance == null;
        instance = this;
        log.info("initialized.");
    }

    public List<DesktopDropEvent> uploads(HttpSession session) {
        assert session != null;
        ArrayList result = new ArrayList(uploads.get(session.getId()));
        uploads.clear();
        return result;
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        log.debug("POST-Request: " + request.getContentType() + ", length: " + request.getContentLength());
        OutputStream fout = null;
        try {
            // copy content into temp file
            final String contentType = request.getContentType();
            File dir = getUploadTempDir(request.getSession());
            final String filename = request.getHeader("X-Filename");
            assert filename != null;
            final File f = new File(dir, filename + "_" + System.currentTimeMillis());
            fout = new FileOutputStream(f);
            IOUtils.copy(request.getInputStream(), fout);
            fout.close();
            log.debug("    uploaded: " + f.getAbsolutePath());

            // create event
            final DesktopDropEvent event = new FileDropEvent() {
                public InputStream getInputStream() throws IOException {
                    return new BufferedInputStream(new FileInputStream(f));
                }

                public String getContentType() {
                    return contentType != null ? contentType : "";
                }

                public String getFileName() {
                    return filename;
                }
            };
            synchronized (uploads) {
                uploads.put(request.getSession().getId(), event);
            }
        } catch (Exception e) {
            log.error(e.getLocalizedMessage(), e);
            //throw new ServletException( e.getLocalizedMessage() );
            response.setStatus(409);
            response.getWriter().append(e.getLocalizedMessage()).flush();
            //sendError( 409, e.getLocalizedMessage() );
        } finally {
            IOUtils.closeQuietly(fout);
        }
    }

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        log.debug("Request: " + request.getQueryString());
    }

    protected String findClientIP(HttpServletRequest request) {
        String forwarded = request.getHeader("X-Forwarded-For");
        if (forwarded != null) {
            return forwarded;
        } else {
            return request.getRemoteHost();
        }
    }

}