GWT实现文件上传下载

主要采用的两个包gwtextux.jar(0.4版本)和commons-fileupload-1.2.1.jar来完成。

在gwt.xml里添加此内容

如你所见,相关JS(在gwtextux.jar包里)放在public/js/下面,与xml对应

 

<module>
      <entry-point class='com.google.gwt.client.test'/>
      <stylesheet src='test.css' />
		<stylesheet src="js/resources/css/ext-all.css" />
	<script src="js/adapter/ext/ext-base.js" />
	<script src="js/ext-all.js" /> 
	 <inherits name="com.gwtext.GwtExt"/>



	        <!-- upload              -->
<servlet path="/UploadSvc" class="com.google.gwt.service.UploadSvcImpl" />
<inherits name="com.gwtextux.GwtExtUx"/>
<inherits name="com.gwtextux.UploadDialog"/>
<script src="js/Ext.ux.UploadDialog.js" />
		<!-- upload              -->

</module>

  客户端:

 import com.google.gwt.core.client.EntryPoint;  
 import com.google.gwt.user.client.ui.RootPanel;  
 import com.gwtext.client.widgets.Button;  
 import com.gwtext.client.widgets.Panel;  
 import com.gwtext.client.widgets.event.ButtonListenerAdapter;  
 import com.gwtext.client.core.EventObject;  
 import com.gwtext.client.core.UrlParam;  
 import com.gwtextux.client.widgets.upload.UploadDialog;  

public class UploadDialogSample implements EntryPoint{  
		 
	 public void onModuleLoad() {  
		 Panel panel = new Panel();  
		 Button button = new Button("Upload File", new ButtonListenerAdapter() {  
		     public void onClick(final Button button, EventObject e) {  
	       UploadDialog dialog = new UploadDialog();  
                        //于xml对应
	       dialog.setUrl("UploadSvc");  
                       //上传文件类型
	       //dialog.setPermittedExtensions(new String[]{"jpg", "gif"}); 
                       //参数
		     UrlParam param[] = new UrlParam[2];  
		     param[0]=new UrlParam("name1", "value1");  
		     param[1]=new UrlParam("name2", "value2");  
		     dialog.setBaseParams(param);  
		                             //上传数据名称 并非文件名
		     dialog.setPostVarName("myvar");  
		     dialog.show();  
			         }  
			     });  
		     panel.add(button);  
		     RootPanel.get().add(panel);  

	     }  
	 }  

 

 

 

 

 

服务端:

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
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 com.google.gwt.core.client.GWT;

public class UploadSvcImpl extends HttpServlet {

	private static final long serialVersionUID = 1L;

	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {

		/*
		 * The following commented code uses Apache Commons Upload
		 */
		// Check that we have a file upload request
		boolean isMultipart = ServletFileUpload.isMultipartContent(req);
		GWT.log("is multipart? " + Boolean.toString(isMultipart), null);
		// Create a new file upload handler
		ServletFileUpload upload = new ServletFileUpload();

		try {
			// Parse the request
			FileItemIterator iter = upload.getItemIterator(req);
			while (iter.hasNext()) {
				FileItemStream item = iter.next();
				String name = item.getFieldName();
				InputStream stream = item.openStream();
				if (item.isFormField()) {
					System.out.println("Form field " + name + " with value "
							+ Streams.asString(stream) + " detected.");
				} else {
					System.out.println("File field " + name
							+ " with file name " + item.getName()
							+ " detected.");
					BufferedInputStream inputStream = new BufferedInputStream(
							stream);// 获得输入流
					BufferedOutputStream outputStream = new BufferedOutputStream(
							new FileOutputStream(new File("/var/app/fax/"
									+ item.getName())));// 获得文件输出流
					Streams.copy(inputStream, outputStream, true); // 开始把文件写到你指定的上传文件夹
				}
				stream.close();
			}
			System.out.println("上传成功!");
		} catch (Exception ex) {
			ex.printStackTrace();
		}
	}

}

 

 

你也可以直接访问http://max-bazhenov.com/dev/upload-dialog-2.0/index.php 

 

 

下载:

grid里双击触发下载

	protected void onGridRowDblClick(GridPanel grid, int rowIndex, EventObject e) {
              // test.rar在 public目录下
		Window.open(GWT.getHostPageBaseURL()+"test.rar", "", "");
	}