org.polymap.rap.updownload.upload.FileUploadServlet.java Source code

Introduction

Here is the source code for org.polymap.rap.updownload.upload.FileUploadServlet.java

Source

/* 
 * polymap.org
 * Copyright (C) 2013, Falko Brutigam. All rights reserved.
 *
 * 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 3.0 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.rap.updownload.upload;

import java.util.Map;

import java.io.IOException;
import java.io.InputStream;

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

import org.apache.commons.fileupload.FileItemIterator;
import org.apache.commons.fileupload.FileItemStream;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.fileupload.util.Streams;
import org.apache.commons.io.IOUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.google.common.collect.MapMaker;

/**
 * 
 *
 * @author <a href="http://www.polymap.de">Falko Brutigam</a>
 */
public class FileUploadServlet extends HttpServlet {

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

    private static Map<String, IUploadHandler> handlers = new MapMaker().concurrencyLevel(2).softValues().makeMap();

    /**
     * Registers the given upload handler with the global upload servlet.
     * 
     * @param handler The handler to register. The handler is stored in a soft reference.
     * @return The URL to use for the given handler.
     */
    public static String addUploadHandler(IUploadHandler handler) {
        String key = String.valueOf(handler.hashCode());
        handlers.put(key, handler);
        return "fileupload?handler=" + key;
    }

    public static boolean removeUploadHandler(IUploadHandler handler) {
        String key = String.valueOf(handler.hashCode());
        return handlers.remove(key) != null;
    }

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

    private ServletFileUpload fileUpload = new ServletFileUpload();

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        try {
            FileItemIterator it = fileUpload.getItemIterator(req);
            while (it.hasNext()) {
                FileItemStream item = it.next();
                String name = item.getFieldName();
                InputStream in = item.openStream();
                try {
                    if (item.isFormField()) {
                        log.info("Form field " + name + " with value " + Streams.asString(in) + " detected.");
                    } else {
                        log.info("File field " + name + " with file name " + item.getName() + " detected.");

                        String key = req.getParameter("handler");
                        assert key != null;
                        IUploadHandler handler = handlers.get(key);
                        // for the upload field we always get just one item (which has the length of the request!?)
                        int length = req.getContentLength();
                        handler.uploadStarted(item.getName(), item.getContentType(), length, in);
                    }
                } finally {
                    IOUtils.closeQuietly(in);
                }
            }
        } catch (Exception e) {
            log.warn("", e);
            throw new RuntimeException(e);
        }
    }

}