struts中获取上传文件的大小
我在做上传文件.我想在点击浏览的时候可以获取文件的大小.请问如何实现. 
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------解决方案--------------------/* 
  * Generated by MyEclipse Struts 
  * Template path: templates/java/JavaClass.vtl 
  */ 
 package demo;   
 import java.io.FileOutputStream; 
 import java.io.InputStream; 
 import java.io.OutputStream; 
 import javax.servlet.http.HttpServletRequest; 
 import javax.servlet.http.HttpServletResponse; 
 import org.apache.struts.action.Action; 
 import org.apache.struts.action.ActionForm; 
 import org.apache.struts.action.ActionForward; 
 import org.apache.struts.action.ActionMapping; 
 import org.apache.struts.upload.FormFile;   
 /** 
  * MyEclipse Struts Creation date: 07-02-2007 
  *  
  * XDoclet definition: 
  *  
  * @struts.action validate= "true " 
  */ 
 public class UploadAction extends Action { 
 	/* 
 	 * Generated Methods 
 	 */   
 	/** 
 	 * Method execute 
 	 *  
 	 * @param mapping 
 	 * @param form 
 	 * @param request 
 	 * @param response 
 	 * @return ActionForward 
 	 */   
 	public ActionForward execute(ActionMapping mapping, ActionForm form, 
 			HttpServletRequest request, HttpServletResponse response) 
 			throws Exception { 
 		// 获取UploadBeanForm 
 		UploadBeanForm uploadBeanForm = (UploadBeanForm) form; 
 		// 从UploadBeanForm里面获取用户要上传的文件 
 		FormFile file = uploadBeanForm.getFile(); 
 		if (file == null) { 
 			return mapping.findForward( " "); 
 		}   
 		// 获取文件相关信息 
 		String fileName = file.getFileName(); 
 		uploadBeanForm.setFilename(fileName); 
 		String size = Integer.toString(file.getFileSize()); 
 		uploadBeanForm.setSize(size);   
 		// 获取文件的输入流 
 		InputStream is = file.getInputStream(); 
 		// 获取文件在服务器上的存储路径。 
 		String storePath = servlet.getServletContext().getRealPath( 
 				 "/fileupload "); 
 		/* storePath为绝对路径 */ 
 		// String storePath =  "F:\\fileupload "; 
 		// 获取文件的输出流 
 		OutputStream os = new FileOutputStream(storePath +  "/ " + fileName); 
 		// 开始上传文件 
 		int bytes = 0; 
 		byte[] buffer = new byte[8192]; 
 		while ((bytes = is.read(buffer, 0, 8192)) != -1) { 
 			os.write(buffer, 0, 8192); 
 		} 
 		// 关闭输出流 
 		os.close(); 
 		// 关闭输入流 
 		is.close(); 
 		// 释放文件连接 
 		file.destroy(); 
 		return mapping.findForward( "fileUpload "); 
 	} 
 }
------解决方案--------------------html可以的,在jsp中也行
------解决方案--------------------jsp和html是一样的。你的那个用js实现的肯定也可以在jsp中用的。