由于存储空间，对一般用户而言，就是用来操作存储文件的，所以这两天，特意看了一下windows下用servlet实现文件上传、下载和删除，下面是详细代码说明
上传：
用的是commons-fileupload-1.2.2.jar和commons-io-2.0.1.jar组件，可以去apache官网上去下载，然后放到WebRoot/WEB-INF/lib目录下
upload.html
<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=GBK"> <title>File upload</title> </head> <body> <!-- action="fileupload"对应web.xml中<servlet-mapping>中<url-pattern>的设置.--> <!-- 必须是multipart的表单数据,才能完整的传递文件数据 --> <form action="fileupload" method="post" enctype="multipart/form-data"> File:<br> <input type="file"><br> <br> <input type="submit" value="Commit"> </form> </body> </html>
web.xml里加上下面几行：
<servlet> <servlet-name>Upload</servlet-name> <servlet-class>am.demo.Upload</servlet-class> </servlet> <servlet-mapping> <servlet-name>Upload</servlet-name> <url-pattern>/fileupload</url-pattern> </servlet-mapping>
src目录下新建文件Upload.java：
package am.demo; import java.io.File; import java.io.IOException; import java.util.Iterator; import java.util.List; 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.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; @SuppressWarnings("serial") public class Upload extends HttpServlet { private String uploadPath = "d://temp"; // 上传文件的目录 @SuppressWarnings("unchecked") public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { try { // Create a factory for disk-based file items DiskFileItemFactory factory = new DiskFileItemFactory(); // Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory); List<FileItem> items = upload.parseRequest(request);// 得到所有的文件 Iterator<FileItem> i = items.iterator(); while (i.hasNext()) { FileItem fi = (FileItem) i.next(); String fileName = fi.getName(); if (fileName != null) { File fullFile = new File(fi.getName()); File savedFile = new File(uploadPath, fullFile.getName()); fi.write(savedFile); } } response.setContentType("text/html;charset=GBK"); response.getWriter().print( "<mce:script language='javascript'><!-- alert('上传成功');window.location.href='index.jsp'; // --></mce:script>"); } catch (Exception e) { // 可以跳转出错页面 e.printStackTrace(); } } public void init() throws ServletException { File uploadFile = new File(uploadPath); if (!uploadFile.exists()) { uploadFile.mkdirs(); } } }
再看下载Downlaod.java:
package am.demo; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.OutputStream; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @SuppressWarnings("serial") public class Download extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { String aFileName = new String(request.getParameter("name").getBytes( "iso8859-1"), "gbk"); File fileLoad = new File("d:/temp", aFileName); FileInputStream in = null; // 输入流 OutputStream out = response.getOutputStream(); byte b[] = new byte[1024]; try { response.setContentType("application/x-msdownload;"); response.setHeader("Content-disposition", "attachment; filename=" + new String(aFileName.getBytes("GBK"), "ISO-8859-1")); // download the file. in = new FileInputStream(fileLoad); int n = 0; while ((n = in.read(b)) != -1) { out.write(b, 0, n); } } catch (Throwable e) { e.printStackTrace(); } finally { try { in.close(); out.close(); } catch (Throwable e) { e.printStackTrace(); } } } public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { doGet(request, response); } }
删除Delete.java:
package am.demo; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @SuppressWarnings("serial") public class Delete extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws FileNotFoundException, IOException { String aFileName = new String(request.getParameter("name").getBytes( "iso8859-1"), "gbk"); File file = new File("d:/temp", aFileName); response.setContentType("text/html;charset=GBK"); if (!file.isDirectory()) { file.delete(); response.getWriter().print( "<mce:script language='javascript'><!-- alert('删除成功');window.location.href='index.jsp'; // --></mce:script>"); } else { } } public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { doGet(request, response); } }