org.zkoss.zul.Filedownload.java 源码

/* Filedownload.java

   Purpose:

   Description:

   History:
         Mon Apr 16 09:29:44     2007, Created by tomyeh

   Copyright (C) 2007 Potix Corporation. All Rights Reserved.

 {{IS_RIGHT
     This program is distributed under LGPL Version 2.1 in the hope that
     it will be useful, but WITHOUT ANY WARRANTY.
 }}IS_RIGHT
*/
 package org.zkoss.zul;

 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.InputStream;
 import java.io.Reader;
 import java.net.URL;

 import org.zkoss.util.media.AMedia;
 import org.zkoss.util.media.Media;
 import org.zkoss.zk.au.DeferredValue;
 import org.zkoss.zk.au.out.AuDownload;
 import org.zkoss.zk.ui.Desktop;
 import org.zkoss.zk.ui.Executions;
 import org.zkoss.zk.ui.sys.WebAppCtrl;

 /**
  * File download utilities.
  *
  * @author tomyeh
  * @see Fileupload
  */
 public class Filedownload {
     /** Open a download dialog to save the specified content at the client.
      */
     public static void save(Media media) {
         save(media, null);
     }

     /** Open a download dialog to save the specified content at the client
      * with the suggested file name.
      *
      * @param media the media to download
      * @param flnm the suggested file name, e.g., myfile.pdf.
      * If null, {@link Media#getName} is assumed.
      */
     public static void save(Media media, String flnm) {
         final Desktop desktop = Executions.getCurrent().getDesktop();
         ((WebAppCtrl) desktop.getWebApp()).getUiEngine().addResponse(new AuDownload(new DownloadURL(media, flnm))); //Bug 2114380
     }

     /** Open a download dialog to save the specified content at the client
      * with the suggested file name.
      *
      * @param content the content
      * @param contentType the content type (a.k.a., MIME type),
      * e.g., application/pdf
      * @param flnm the suggested file name, e.g., myfile.pdf.
      * If null, no suggested name is provided.
      */
     public static void save(byte[] content, String contentType, String flnm) {
         save(new AMedia(flnm, null, contentType, content), flnm);
     }

     /** Open a download dialog to save the specified content at the client
      * with the suggested file name.
      *
      * @param content the content
      * @param contentType the content type (a.k.a., MIME type),
      * e.g., application/pdf
      * @param flnm the suggested file name, e.g., myfile.pdf.
      * If null, no suggested name is provided.
      */
     public static void save(String content, String contentType, String flnm) {
         save(new AMedia(flnm, null, contentType, content), flnm);
     }

     /** Open a download dialog to save the specified content at the client
      * with the suggested file name.<br/>
      * Note: You don't need to close the content (a InputStream), it will be closed automatically after download.
      * @param content the content
      * @param contentType the content type (a.k.a., MIME type),
      * e.g., application/pdf
      * @param flnm the suggested file name, e.g., myfile.pdf.
      * If null, no suggested name is provided.
      */
     public static void save(InputStream content, String contentType, String flnm) {
         save(new AMedia(flnm, null, contentType, content), flnm);
     }

     /** Open a download dialog to save the specified content at the client
      * with the suggested file name.<br/>
      * Note: You don't need to close the content (a Reader), it will be closed automatically after download.
      * @param content the content
      * @param contentType the content type (a.k.a., MIME type),
      * e.g., application/pdf
      * @param flnm the suggested file name, e.g., myfile.pdf.
      * If null, no suggested name is provided.
      */
     public static void save(Reader content, String contentType, String flnm) {
         save(new AMedia(flnm, null, contentType, content), flnm);
     }

     /** Open a download dialog to save the specified file at the client.
      *
      * @param file the file to download to the client
      * @param contentType the content type, e.g., application/pdf.
      * Unlike other save methods, it is optional. If null, the file name's
      * extension is used to determine the content type.
      * @exception FileNotFoundException if the file is not found.
      * @since 3.0.8
      */
     public static void save(File file, String contentType) throws FileNotFoundException {
         save(new AMedia(file, contentType, null), file.getName());
     }

     /** Open a download dialog to save the resource of the specified URL
      * at the client.
      * The path must be retrievable by use of {@link org.zkoss.zk.ui.WebApp#getResource}.
      *
      * @param url the URL to get the resource
      * @param contentType the content type, e.g., application/pdf.
      * Unlike other save methods, it is optional. If null, the path's
      * extension is used to determine the content type.
      * @exception FileNotFoundException if the resource is not found.
      * @since 3.0.8
      */
     public static void save(URL url, String contentType) throws FileNotFoundException {
         String name = url.toExternalForm();
         int j = name.lastIndexOf('/');
         if (j >= 0 && j < name.length() - 1)
             name = name.substring(j + 1);
         save(new AMedia(url, contentType, null), name);
     }

     /** Open a download dialog to save the resource of the specified path
      * at the client.
      *
      * @param path the path of the resource.
      * It must be retrievable by use of {@link org.zkoss.zk.ui.WebApp#getResource}.
      * @param contentType the content type, e.g., application/pdf.
      * Unlike other save methods, it is optional. If null, the path's
      * extension is used to determine the content type.
      * @exception FileNotFoundException if the resource is not found.
      * @since 3.0.8
      */
     public static void save(String path, String contentType) throws FileNotFoundException {
         final URL url = Executions.getCurrent().getDesktop().getWebApp().getResource(path);
         if (url == null)
             throw new FileNotFoundException(path);
         save(url, contentType);
     }

     private static class DownloadURL implements DeferredValue {
         private final Media _media;
         private final String _path;

         private DownloadURL(Media media, String flnm) {
             _media = media;

             if (flnm == null)
                 flnm = media.getName();

             final StringBuffer sb = new StringBuffer(32);
             if (flnm != null && flnm.length() != 0) {
                 sb.append('/');
                 sb.append(flnm);
                 if (flnm.lastIndexOf('.') < 0) {
                     final String format = media.getFormat();
                     if (format != null)
                         sb.append('.').append(format);
                 }
             }
             _path = sb.toString();
         }

         public Object getValue() {
             return Executions.getCurrent().getDesktop().getDownloadMediaURI(_media, _path);
         }
     }
 }