struts上传下载实现
在god老大的激励之下，我开始着手做这个上传下载了，由于它只是个作业，所以我能做的就是完成它，完美和时间的权衡下，时间最重要，我花了一个星期使用不熟练的struts来写程序，对于struts的精神理解已经很透彻了，只是struts标签库里的东西，各种form还没有完全熟悉，呵呵，反正god老大的东西不要struts开发，这也为程序留下缺陷埋下伏笔。下面列出我的代码：
上传：
selfile.jsp
<%@ page language="java"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html" prefix="html"%>
------------------------------------------------------------------------------------
UploadForm.java
package com.vv.struts.form;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts.action.*;
import org.apache.struts.upload.*;
/**
*
Title:UpLoadForm
*
Description: QRRSMMS
*
Copyright: Copyright (c) 2004 jiahansoft
*
Company: jiahansoft
* @author wanghw
* @version 1.0
*/
public class UploadForm extends ActionForm {
public static final String ERROR_PROPERTY_MAX_LENGTH_EXCEEDED = "org.apache.struts.webapp.upload.MaxLengthExceeded";
protected FormFile theFile;
public FormFile getTheFile() {
return theFile;
}
public void setTheFile(FormFile theFile) {
this.theFile = theFile;
}
public ActionErrors validate(ActionMapping mapping, HttpServletRequest request)
{
ActionErrors errors = null;
//has the maximum length been exceeded?
Boolean maxLengthExceeded = (Boolean)
request.getAttribute(MultipartRequestHandler.ATTRIBUTE_MAX_LENGTH_EXCEEDED);
if ((maxLengthExceeded != null) && (maxLengthExceeded.booleanValue()))
{
errors = new ActionErrors();
errors.add(ERROR_PROPERTY_MAX_LENGTH_EXCEEDED, new ActionError("maxLengthExceeded"));
}
return errors;
}
}
-------------------------------------------------------------------------------------
UploadAction.java
package com.vv.struts.action;
import java.io.*;
import javax.servlet.http.*;
import org.apache.struts.action.*;
import org.apache.struts.upload.FormFile;
import com.vv.struts.form.UploadForm;
/**
*
Title:UpLoadAction
*
Description: QRRSMMS
*
Copyright: Copyright (c) 2004 jiahansoft
*
Company: jiahansoft
* @author wanghw
* @version 1.0
*/
public class UploadAction extends Action {
public ActionForward execute(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
throws Exception {
if(form==null) System.out.println("null");
if (form instanceof UploadForm) {//如果form是uploadsForm
String encoding = request.getCharacterEncoding();
if ((encoding != null) && (encoding.equalsIgnoreCase("utf-8")))
{
response.setContentType("text/html; charset=gb2312");//如果没有指定编码，编码格式为gb2312
}
UploadForm theForm = (UploadForm ) form;
FormFile file = theForm.getTheFile();//取得上传的文件
try {
InputStream stream = file.getInputStream();//把文件读入
String filePath = request.getRealPath("/");//取当前系统路径
ByteArrayOutputStream baos = new ByteArrayOutputStream();
OutputStream bos = new FileOutputStream(filePath + "/file/" +
file.getFileName());//建立一个上传文件的输出流
//System.out.println(filePath+"/"+file.getFileName());
int bytesRead = 0;
byte[] buffer = new byte[8192];
while ( (bytesRead = stream.read(buffer, 0, 8192)) != -1) {
bos.write(buffer, 0, bytesRead);//将文件写入服务器
}
bos.close();
stream.close();
}catch(Exception e){
System.err.print(e);
}
//request.setAttribute("dat",file.getFileName());
return mapping.findForward("success");
}
return null;
}
}
其它的都是几个次要的页面，老实这部分基本上就是我抄的，虽然我也能写，但是他确实比我写的好，特别是对struts的字段的使用，这些都是我不知道的，我做的只是修改成我要的程序，唯一不好的就是它使用request.getRealPath("/")，这个方法很危险，可是一时间我没有找到更好的方法代替它，这些是可以避免的，为什么使用它和后面的下载有关系，呵呵。
下载：
test.jsp
<%@ page language="java"%>
---------------------------------------------------------------------------
download.jsp
<%@ page language="java" contentType="text/html;charset=UTF-8"%>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-bean" prefix="bean" %>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-html" prefix="html" %>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-logic" prefix="logic" %>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-tiles" prefix="tiles" %>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-template" prefix="template" %>
<%@ taglib uri="http://jakarta.apache.org/struts/tags-nested" prefix="nested" %>
xmlns:w="urn:schemas-microsoft-com:office:word"
xmlns="http://www.w3.org/TR/REC-html40">
对于struts的标签一直不是很理解，在做这个的时候受了不少的苦呀，原来iterate里的row可以作为html:link的属性值，我一直都不知道怎么来动态生成需要的链接，看了好多的例子，甚至在action里要输出到jsp的字符串上再加入字符串“
DownloadAction.java
package com.vv.struts.action;
import org.apache.struts.action.*;
import javax.servlet.http.*;
import java.io.File;
import java.util.*;
/**
*
Title:DownloadWordAction
*
Description: QRRSMMS
*
Copyright: Copyright (c) 2004 jiahansoft
*
Company: jiahansoft
* @author wanghw
* @version 1.0
*/
public class DownloadAction extends Action {
File myDir;
File[] contents;
public ActionForward execute(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
throws Exception {
DynaActionForm testForm = (DynaActionForm)form;
testForm.set("name","a test word");
ArrayList list = new ArrayList();
String path=request.getRealPath("/")+"file";
String FullPath;
System.out.println(path);
myDir=new File(path);
list.clear();
contents=myDir.listFiles();
//HashMap row = new HashMap();
//System.out.println(contents.length);
for(int i=0;i
//row.put("1",FullPath);
list.add(FullPath);
System.out.println(FullPath);
}
request.setAttribute("list",list);
return mapping.findForward("display");
}
}
又用了限制级的方法，我也不想的我已用相对路径它就报错，我必须承认，这个写的不够标准，应该用资源文件存储文件路径，而不是反复列举，为什么我不用呢？我当时忘了可以用资源文件了。。。。。。。
LoadedForm.java
package com.vv.struts.form;
import org.apache.struts.action.ActionForm;
/**
* MyEclipse Struts
* Creation date: 05-18-2006
*
* XDoclet definition:
* @struts:form name="loadedForm"
*/
public class LoadedForm extends ActionForm {
// --------------------------------------------------------- Instance Variables
/** name property */
private String name;
/**
* Returns the name.
* @return String
*/
public String getName() {
return name;
}
/**
* Set the name.
* @param name The name to set
*/
public void setName(String name) {
this.name = name;
}
}
---------------------------------------------------------------------------------
LoadedAction.java
package com.vv.struts.action;
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 java.io.*;
import com.vv.struts.form.LoadedForm;
/**
* MyEclipse Struts
* Creation date: 05-17-2006
*
* XDoclet definition:
* @struts:action validate="true"
*/
public class LoadedAction extends Action {
// --------------------------------------------------------- Instance Variables
// --------------------------------------------------------- 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{
LoadedForm doc=(LoadedForm)form;
//if(form==null) System.out.println("null");
String docName = doc.getName();
File f;
if(docName!=""){
String docFullPath=request.getRealPath("/");
//System.out.println(docFullPath);
String Name = docName.substring(0,docName.lastIndexOf("."));
String prefix = docName.substring(docName.lastIndexOf("."));
//byte[] dn=Name.getBytes("UTF-8");
//Name =new String(dn,"ISO-8859-1");
//Name=java.net.URLEncoder.encode(Name,"GBK");
docName = Name +prefix;
System.out.println();
System.out.println(docName);
f = new File(docFullPath+"file//"+docName);
if (!f.exists())
{
return (mapping.findForward("nofile"));
}
BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));
byte[] buf = new byte[1024];
int len = 0;
response.reset();
response.setContentType("application/x-msdownload;charset=UTF-8");
response.setHeader("Content-Disposition", "attachment; filename=" +docName);
OutputStream out = response.getOutputStream();
while((len = br.read(buf)) >0)
out.write(buf,0,len);
br.close();
out.close();
return mapping.findForward("download");
}
return mapping.findForward("nofile");
}
}
我还是不幸运的遇见中文乱码问题，如果下载的是中文文件的话，那么name的值就是乱码，虽然我用了转换字符的代码，可惜事实上它没有用，在：http://www.mx68.com/WebDeveloper/Print.asp?ArticleID=41762&Page=1中的三个方法我都使用了，可是都没什么太大的变化，只是显示不同的乱码而已，郁闷。实在不行了，只能把这篇不怎么样的作业上交god了。作为个程序员来说，它应该是追求完美的，但是我认为效率和时间是个凸函数，并不是但方面的极致就是最好，两者的最佳切合点才是最好。