文件操作java源码

package ds.sw.servlet;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.io.UnsupportedEncodingException;import java.net.URLEncoder;import java.util.Arrays;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.UUID;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.commons.fileupload.FileItem;import org.apache.commons.fileupload.FileUploadBase;import org.apache.commons.fileupload.disk.DiskFileItemFactory;import org.apache.commons.fileupload.servlet.ServletFileUpload;public class FileServlet extends HttpServlet {private static final long serialVersionUID = 1L;public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {request.setCharacterEncoding("utf-8");String method = request.getParameter("method");if(method.equals("upload")){upload(request,response);}else if(method.equals("listfile")){listAll(request,response);}else if(method.equals("listMuban")){listMuban(request,response);}else if(method.equals("download")){download(request,response);}else if(method.equals("downloadM")){downloadM(request,response);}else if(method.equals("delete")){delete(request,response);}else if(method.equals("deleteM")){deleteM(request,response);}else{request.getRequestDispatcher("/back/error.jsp");}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {this.doGet(request, response);}@SuppressWarnings("rawtypes")public void upload(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{//限定文件类型List types = Arrays.asList("doc","docx","zip","rar");//创建磁盘工厂DiskFileItemFactory factory = new DiskFileItemFactory();factory.setSizeThreshold(1024*1024*5);//设置缓存区大小为5Mfactory.setRepository(new File(this.getServletContext().getRealPath("/WEB-INF/file/temp")));//设置缓存区文件夹所在目录为当前项目下的temp文件夹//创建解析器ServletFileUpload jiexiqi = new ServletFileUpload(factory);jiexiqi.setHeaderEncoding("utf-8");//设置文件名的编码方式//限定文件大小jiexiqi.setSizeMax(1024*1024*5);//设置上传文件的最大值不能超过5Mtry {//解析完成后生成一个文件项目列表listList<FileItem> list = jiexiqi.parseRequest(request);for(FileItem item:list){if(item.isFormField()){//为普通输入项String inputName = item.getFieldName();String inputValue = item.getString("utf-8");//设置输入项编码方式System.out.println(inputName + "=" +inputValue);}else{//代表item封装的是上传文件String filename = item.getName().substring(item.getName().lastIndexOf("\\")+1);//获取文件名if(filename.equals(null)||filename.trim().equals("")){request.setAttribute("message","你还没选择上传文件，请反回重新选择上传的文件！");request.getRequestDispatcher("/back/message.jsp").forward(request, response);return;}//限定文件上传了类型String ext = filename.substring((filename.lastIndexOf(".")+1));    //获得文件扩展名if(!types.contains(ext)){request.setAttribute("message","本系统不支持 ."+ext+" 格式的文件上传！");request.getRequestDispatcher("/back/message.jsp").forward(request, response);return;}InputStream in =item.getInputStream();int len = 0;byte buffer[] =new byte[1024];String savepath = this.getServletContext().getRealPath("/WEB-INF/file/download");String saveFileName = uniqueFileName(filename);FileOutputStream out = new FileOutputStream(savepath+File.separator +saveFileName);//File.separator用于生成分隔符，避免操作系统误判while((len = in.read(buffer))>0){out.write(buffer, 0, len);}in.close();out.close();item.delete();//删除缓存区临时文件} }}catch(FileUploadBase.SizeLimitExceededException e1){request.setAttribute("message","上传文件大小不能超过5M");request.getRequestDispatcher("/back/message.jsp").forward(request, response);return;} catch (Exception e) {throw new RuntimeException(e);}request.setAttribute("message","你的文件已经上传成功！");request.getRequestDispatcher("/back/message.jsp").forward(request, response);}@SuppressWarnings("rawtypes")public void listAll(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String path = this.getServletContext().getRealPath("/WEB-INF/file/upload");Map map = new HashMap();listfile(new File(path),map);request.setAttribute("map",map);request.getRequestDispatcher("/back/listfile.jsp").forward(request, response);}@SuppressWarnings("rawtypes")public void listMuban(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String path = this.getServletContext().getRealPath("/WEB-INF/file/download");Map map = new HashMap();listfile(new File(path),map);request.setAttribute("map",map);request.getRequestDispatcher("/back/listMuban.jsp").forward(request, response);}@SuppressWarnings({ "rawtypes", "unchecked" })public void listfile(File file,Map map){if(!file.isFile()){File children[] = file.listFiles();for(File f : children){listfile(f, map);}}else{String filename = file.getName().substring(file.getName().indexOf("_")+1);map.put(file.getName(),filename); }}public void download(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {// 得到要下载的文件名 uuidString filename = request.getParameter("filename");filename = new String(filename.getBytes("iso8859-1"), "UTF-8");// 找出这个文件 url c:\\String path = this.getServletContext().getRealPath("/WEB-INF/file/upload") ;File file = new File(path + File.separator +filename);if (!file.exists()) {request.setAttribute("message", "对不起，您要下载的资源已被删除");request.getRequestDispatcher("/back/message.jsp").forward(request,response);return;}// 得到文件的原始文件名String oldname = file.getName().substring(file.getName().indexOf("_") + 1);// 通知浏览器以下载方式打开下面发送的数据response.setHeader("content-disposition", "attachment;filename="+ URLEncoder.encode(oldname, "UTF-8"));FileInputStream in = new FileInputStream(file);int len = 0;byte buffer[] = new byte[1024];OutputStream out = response.getOutputStream();while ((len = in.read(buffer)) > 0) {out.write(buffer, 0, len);}in.close();}public void delete(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{// 得到要下载的文件名 uuidString filename = request.getParameter("filename");filename = new String(filename.getBytes("iso8859-1"), "UTF-8");// 找出这个文件 url c:\\String path = this.getServletContext().getRealPath("/WEB-INF/file/upload") ;File file = new File(path + File.separator +filename);if (!file.exists()) {request.setAttribute("message", "对不起，您要删除的资源不存在");request.getRequestDispatcher("/back/message.jsp").forward(request,response);}else {file.delete();request.setAttribute("message", filename.substring(filename.lastIndexOf("_")+1)+"已被成功删除！");request.getRequestDispatcher("/back/message.jsp").forward(request,response);}}public void downloadM(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {// 得到要下载的文件名 uuidString filename = request.getParameter("filename");filename = new String(filename.getBytes("iso8859-1"), "UTF-8");// 找出这个文件 url c:\\String path = this.getServletContext().getRealPath("/WEB-INF/file/download") ;File file = new File(path + File.separator +filename);if (!file.exists()) {request.setAttribute("message", "对不起，您要下载的资源已被删除");request.getRequestDispatcher("/back/message.jsp").forward(request,response);return;}// 得到文件的原始文件名String oldname = file.getName().substring(file.getName().indexOf("_") + 1);// 通知浏览器以下载方式打开下面发送的数据response.setHeader("content-disposition", "attachment;filename="+ URLEncoder.encode(oldname, "UTF-8"));FileInputStream in = new FileInputStream(file);int len = 0;byte buffer[] = new byte[1024];OutputStream out = response.getOutputStream();while ((len = in.read(buffer)) > 0) {out.write(buffer, 0, len);}in.close();}public void deleteM(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{// 得到要下载的文件名 uuidString filename = request.getParameter("filename");filename = new String(filename.getBytes("iso8859-1"), "UTF-8");// 找出这个文件 url c:\\String path = this.getServletContext().getRealPath("/WEB-INF/file/download") ;File file = new File(path + File.separator +filename);if (!file.exists()) {request.setAttribute("message", "对不起，您要删除的资源不存在");request.getRequestDispatcher("/back/message.jsp").forward(request,response);}else {file.delete();request.setAttribute("message", filename.substring(filename.lastIndexOf("_")+1)+"已被成功删除！");request.getRequestDispatcher("/back/message.jsp").forward(request,response);}}public  String uniqueFileName(String filename){//该方法用于生成唯一文件名，避免文件被覆盖掉return UUID.randomUUID().toString()+"_"+filename;}}