分类： 系统运维
2009-08-18 10:07:57
使用FileUploadStatus这个类记录文件上传状态，并将其作为服务器端与web客户端之间通信的媒介，通过对这个类对象提供上传状态作为服务器回应发送给web客户端，web客户端使用JavaScript获得文件上传状态。源代码如下：
/**
* 本例程演示了通过Web上传文件过程中的进度显示。您可以对本例程进行任何修改和使用。
*
* 如需要转载，请注明作者。
*
* 作者： 刘作晨
*
*/
package liuzuochen.sample.upload;
import java.util.*;
public class FileUploadStatus {
//上传用户地址
private String uploadAddr;
//上传总量
private long uploadTotalSize = 0;
//读取上传总量
private long readTotalSize = 0;
//当前上传文件号
private int currentUploadFileNum = 0;
//成功读取上传文件数
private int successUploadFileCount = 0;
//状态
private String status = "";
//处理起始时间
private long processStartTime = 0l;
//处理终止时间
private long processEndTime = 0l;
//处理执行时间
private long processRunningTime = 0l;
//上传文件URL列表
private List uploadFileUrlList = new ArrayList();
//取消上传
private boolean cancel = false;
//上传base目录
private String baseDir = "";
public FileUploadStatus() {
}
public String getBaseDir() {
return baseDir;
}
public void setBaseDir(String baseDir) {
this.baseDir = baseDir;
}
public boolean getCancel() {
return cancel;
}
public void setCancel(boolean cancel) {
this.cancel = cancel;
}
public List getUploadFileUrlList() {
return uploadFileUrlList;
}
public void setUploadFileUrlList(List uploadFileUrlList)
{ this.uploadFileUrlList = uploadFileUrlList;
}
public long getProcessRunningTime() {
return processRunningTime;
}
public void setProcessRunningTime(long
processRunningTime) {
this.processRunningTime = processRunningTime;
}
public long getProcessEndTime() {
return processEndTime;
}
public void setProcessEndTime(long processEndTime) {
this.processEndTime = processEndTime;
}
public long getProcessStartTime() {
return processStartTime;
}
public void setProcessStartTime(long processStartTime) {
this.processStartTime = processStartTime;
}
public long getReadTotalSize() {
return readTotalSize;
}
public void setReadTotalSize(long readTotalSize) {
this.readTotalSize = readTotalSize;
}
public int getSuccessUploadFileCount() {
return successUploadFileCount;
}
public void setSuccessUploadFileCount(int
successUploadFileCount) {
this.successUploadFileCount =
successUploadFileCount;
}
public int getCurrentUploadFileNum() {
return currentUploadFileNum;
}
public void setCurrentUploadFileNum(int
currentUploadFileNum) {
this.currentUploadFileNum = currentUploadFileNum;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public long getUploadTotalSize() {
return uploadTotalSize;
}
public String getUploadAddr() {
return uploadAddr;
}
public void setUploadTotalSize(long uploadTotalSize) {
this.uploadTotalSize = uploadTotalSize;
}
public void setUploadAddr(String uploadAddr) {
this.uploadAddr = uploadAddr;
}
public String toJSon() {
StringBuffer strJSon = new StringBuffer();
strJSon.append("
{UploadTotalSize:").append(getUploadTotalSize()).append(
",")
.append
("ReadTotalSize:").append(getReadTotalSize()).append
(",")
.append
("CurrentUploadFileNum:").append(getCurrentUploadFileNum()).
append(",")
.append
("SuccessUploadFileCount:").append(
getSuccessUploadFileCount()).append(",") .append
("Status:'").append(getStatus()).append("',") .append
("ProcessStartTime:").append(getProcessStartTime()). append(",")
.append("ProcessEndTime:").append(getProcessEndTime()).append( ",")
.append("ProcessRunningTime:").append(getProcessRunningTime()).
append(",") .append("Cancel:").append(getCancel()).append("}");
return strJSon.toString();
}
}
使用Common-FileUpload 1.2版本(20070103)。此版本提供了能够监视文件上传情况的 ProcessListener接口，
使开发者通过FileUploadBase类对象的setProcessListener方法植入自己的Listener。
FileUploadListener类实现了ProcessListener，在整个文件上传过程中，它对上传进度进行监控，
并且根据上传 情况实时的更新上传状态Bean。源代码如下：
/**
* 本例程演示了通过Web上传文件过程中的进度显示。您可以对本例程进行任何修改和使用。
*
* 如需要转载，请注明作者。
*
* 作者： 刘作晨
*
*/
package liuzuochen.sample.upload;
import org.apache.commons.fileupload.ProgressListener;
import javax.servlet.http.HttpServletRequest;
public class FileUploadListener implements ProgressListener{
private HttpServletRequest request=null;
public FileUploadListener(HttpServletRequest request){
this.request=request;
}
/**
* 更新状态
*/
public void update(long pBytesRead, long pContentLength, int pItems){
FileUploadStatus statusBean= BackGroundService.getStatusBean(request);
statusBean.setUploadTotalSize(pContentLength);
//读取完成
if (pContentLength == -1) {
statusBean.setStatus("完成对" + pItems +"个文件的读取:读取了 " + pBytesRead + " bytes.");
statusBean.setReadTotalSize(pBytesRead);
statusBean.setSuccessUploadFileCount(pItems);
statusBean.setProcessEndTime(System.currentTimeMillis());
statusBean.setProcessRunningTime(statusBean.getProcessEndTime());
//读取中
} else {
statusBean.setStatus("当前正在处理第" + pItems +"个文件:已经读取了 " + pBytesRead + " / " + pContentLength+ " bytes.");
statusBean.setReadTotalSize(pBytesRead);
statusBean.setCurrentUploadFileNum(pItems);
statusBean.setProcessRunningTime(System.currentTimeMillis());
}
BackGroundService.saveStatusBean(request,statusBean);
}
}
BackGroundService这个Servlet类负责接收Form Post数据、回应状态轮询请求、处理取消文件上传的请求。
尽管可以把这些功能相互分离开来，但为了简单明了，还是将它们放到Servlet中，只是由不同的方法进行分割。
源代码如下：
/**
* 本例程演示了通过Web上传文件过程中的进度显示。您可以对本例程进行任何修改和使用。
*
* 如需要转载，请注明作者。
*
* 作者： 刘作晨
*
*/
package liuzuochen.sample.upload;
import java.io.File;
import java.io.IOException;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.*;
public class BackGroundService extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
public static final String UPLOAD_DIR = "/upload";
public static final String DEFAULT_UPLOAD_FAILURE_URL = "./result.jsp";
public BackGroundService() {
super();
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
/**
* 从文件路径中取出文件名
*/
private String takeOutFileName(String filePath) {
int pos = filePath.lastIndexOf(File.separator);
if (pos > 0) {
return filePath.substring(pos + 1);
} else {
return filePath;
}
}
/**
* 从request中取出FileUploadStatus Bean
*/
public static FileUploadStatus getStatusBean(
HttpServletRequest request) {
BeanControler beanCtrl = BeanControler.getInstance();
return beanCtrl.getUploadStatus(request.getRemoteAddr());
}
/**
* 把FileUploadStatus Bean保存到类控制器BeanControler
*/
public static void saveStatusBean( HttpServletRequest request, FileUploadStatus statusBean) {
statusBean.setUploadAddr(request.getRemoteAddr());
BeanControler beanCtrl = BeanControler.getInstance();
beanCtrl.setUploadStatus(statusBean);
}
/**
* 删除已经上传的文件
*/
private void deleteUploadedFile(HttpServletRequest request) {
FileUploadStatus satusBean = getStatusBean(request);
for (int i = 0; i < satusBean.getUploadFileUrlList().size(); i++) {
File uploadedFile = new File(request.getRealPath(UPLOAD_DIR) + File.separator + satusBean.getUploadFileUrlList(). get(i));
uploadedFile.delete();
}
satusBean.getUploadFileUrlList().clear();
satusBean.setStatus("删除已上传的文件");
saveStatusBean(request, satusBean);
}
/**
* 上传过程中出错处理
*/
private void uploadExceptionHandle( HttpServletRequest request, String errMsg) throws ServletException, IOException {
//首先删除已经上传的文件
deleteUploadedFile(request);
FileUploadStatus satusBean = getStatusBean(request);
satusBean.setStatus(errMsg);
saveStatusBean(request, satusBean);
}
/**
* 初始化文件上传状态Bean
*/
private FileUploadStatus initStatusBean(HttpServletRequest
request) {
FileUploadStatus satusBean = new FileUploadStatus();
satusBean.setStatus("正在准备处理");
satusBean.setUploadTotalSize(request.getContentLength());
satusBean.setProcessStartTime(System.currentTimeMillis());
satusBean.setBaseDir(request.getContextPath() + UPLOAD_DIR);
return satusBean;
}
/**
* 处理文件上传
*/
private void processFileUpload(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
DiskFileItemFactory factory = new DiskFileItemFactory();
//设置内存缓冲区，超过后写入临时文件
factory.setSizeThreshold(10240000);
//设置临时文件存储位置
factory.setRepository(new File(request.getRealPath("/upload/temp")));
ServletFileUpload upload = new ServletFileUpload(factory);
//设置单个文件的最大上传值
upload.setFileSizeMax(102400000);
//设置整个request的最大值
upload.setSizeMax(102400000);
upload.setProgressListener(new FileUploadListener(request));
//保存初始化后的FileUploadStatus Bean
saveStatusBean(request, initStatusBean(request));
String forwardURL = "";
try {
List items = upload.parseRequest(request);
//获得返回url
for (int i = 0; i < items.size(); i++) {
FileItem item = (FileItem) items.get(i);
if (item.isFormField()) {
forwardURL = item.getString();
break;
}
}
//处理文件上传
for (int i = 0; i < items.size(); i++) {
FileItem item = (FileItem) items.get(i);
//取消上传
if (getStatusBean(request).getCancel()) {
deleteUploadedFile(request);
break;
}
//保存文件
else if (!item.isFormField() && item.getName().length() > 0) {
String fileName = takeOutFileName(item.getName());
File uploadedFile = new File(request.getRealPath(UPLOAD_DIR) +
File.separator + fileName); item.write(uploadedFile); //更新上传文件列表 FileUploadStatus
satusBean = getStatusBean(request);
satusBean.getUploadFileUrlList().add(fileName);
saveStatusBean(request, satusBean);
Thread.sleep(500);
}
}
} catch (FileUploadException e) {
uploadExceptionHandle(request, "上传文件时发生错误:" + e.getMessage());
} catch (Exception e) {
uploadExceptionHandle(request, "保存上传文件时发生错误:" + e.getMessage());
}
if (forwardURL.length() == 0) {
forwardURL = DEFAULT_UPLOAD_FAILURE_URL;
}
request.getRequestDispatcher(forwardURL).forward(request, response);
}
/**
* 回应上传状态查询
*/
private void responseStatusQuery(HttpServletRequest request,
HttpServletResponse response) throws IOException {
response.setContentType("text/xml");
response.setCharacterEncoding("UTF-8");
response.setHeader("Cache-Control", "no-cache");
FileUploadStatus satusBean = getStatusBean(request);
response.getWriter().write(satusBean.toJSon());
}
/**
* 处理取消文件上传
*/
private void processCancelFileUpload(HttpServletRequest request,
HttpServletResponse response) throws IOException {
FileUploadStatus satusBean = getStatusBean(request);
satusBean.setCancel(true);
saveStatusBean(request, satusBean);
responseStatusQuery(request, response);
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (isMultipart) {
processFileUpload(request, response);
} else {
request.setCharacterEncoding("UTF-8");
if (request.getParameter("uploadStatus") != null) {
responseStatusQuery(request, response);
}
if (request.getParameter("cancelUpload") != null) {
processCancelFileUpload(request, response);
}
}
}
}
这是一个单例类，它的功能是为客户端保存文件上传状态，这里我没有使用Session来存储 文件上传状态，
因为对于AJAX这种异步调用，服务器会开启不同的Session，所以无法通过Session保存文件上传状态。
我并不认为这种方法最好，如果有更好的方法，欢迎大家一起讨论。 源代码如下：
/**
* 本例程演示了通过Web上传文件过程中的进度显示。您可以对本例程进行任何修改和使用。
*
* 如需要转载，请注明作者。
*
* 作者： 刘作晨
*
*/
package liuzuochen.sample.upload;
import java.util.Vector;
public class BeanControler {
private static BeanControler beanControler = new BeanControler();
private Vector vector = new Vector();
private BeanControler() {
}
public static BeanControler getInstance() {
return beanControler;
}
/**
* 取得相应FileUploadStatus类对象的存储位置
*/
private int indexOf(String strID) {
int nReturn = -1;
for (int i = 0; i < vector.size(); i++) {
FileUploadStatus status = (FileUploadStatus) vector.elementAt(i);
if (status.getUploadAddr().equals(strID)) {
nReturn = i;
break;
}
}
return nReturn;
}
/**
* 取得相应FileUploadStatus类对象
*/
public FileUploadStatus getUploadStatus(String strID) {
return (FileUploadStatus) vector.elementAt(indexOf(strID));
}
/**
* 存储FileUploadStatus类对象
*/
public void setUploadStatus(FileUploadStatus status) {
int nIndex = indexOf(status.getUploadAddr());
if ( -1 == nIndex) {
vector.add(status);
} else {
vector.insertElementAt(status, nIndex);
vector.removeElementAt(nIndex + 1);
}
}
/**
* 删除FileUploadStatus类对象
*/
public void removeUploadStatus(String strID){
int nIndex = indexOf(strID);
if(-1!=nIndex)
vector.removeElementAt(nIndex);
}
}
