功能文件的上传,下载和管理
技术:1.用xml当做数据库存储信息(dom4j,xpath)
2.Java表单的文件上传和下载
3.文件目录的打散 ( Hash目录是一种优化文件存储性能的方法)
需要的jar包:
commons-fileupload-1.2.2.jar、commons-io-2.1.jar、dom4j-1.6.1.jar和jaxen-1.1-beta-6.jar
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先写index.jsp
<%@ page language=\"java\" import=\"java.util.*\" pageEncoding=\"utf-8\"%> <!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\"> <html> <head> <title>相册管理系统</title> </head> <body> <h1>我的小相册</h1> <a href=\"jsps/upload.jsp\">上传相册</a> <a href=\"servlets/ShowServlet\">浏览相册</a> </body> </html>
upload.jsp是下载页面放在jsps目录下
<%@ page language=\"java\" import=\"java.util.*\" pageEncoding=\"UTF-8\"%> <!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\"> <html> <head> </head> <body> <h1>相处上传</h1> <form action=\"<%=request.getContextPath()%>/servlets/UploadServlet\" method=\"post\" enctype=\"multipart/form-data\"> 文件:<input type=\"file\" name=\"file1\"/><br/> 说明:<input type=\"text\" name=\"desc\" /><br/> <input type=\"submit\" value=\"上传\" /> </form> </body> </html>
photos.xml放在src目录下
<?xml version=\"1.0\" encoding=\"UTF-8\"?> <photos> </photos>
在写值对象PhotoModel
package cn.hncu.demain; public class PhotoModel { private String id; private String realName; private String ext; private String dir; private String dateTime; private String ip; private String desc; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getRealName() { return realName; } public void setRealName(String realName) { this.realName = realName; } public String getExt() { return ext; } public void setExt(String ext) { this.ext = ext; } public String getDir() { return dir; } public void setDir(String dir) { this.dir = dir; } public String getDateTime() { return dateTime; } public void setDateTime(String dateTime) { this.dateTime = dateTime; } public String getIp() { return ip; } public void setIp(String ip) { this.ip = ip; } public String getDesc() { return desc; } public void setDesc(String desc) { this.desc = desc; } @Override public String toString() { return \"PhotoModel [id=\" + id + \", realName=\" + realName + \", ext=\" + ext + \", dir=\" + dir + \", dateTime=\" + dateTime + \", ip=\" + ip + \", desc=\" + desc + \"]\"; } }
写工具类两个:
MyUtil(日期格式化,目录打散代码,随机id代码)
package cn.hncu.utils; import java.text.SimpleDateFormat; import java.util.Date; import java.util.UUID; public class MyUtils { private MyUtils() { } private static SimpleDateFormat format=new SimpleDateFormat(\"yyyy年MM月dd日 hh:mm:ss\"); public static String getCurrentDateTime(){ return format.format(new Date()); } public static String getUUid(){ UUID uuid=UUID.randomUUID(); String id=uuid.toString().replaceAll(\"-\", \"\"); return id; } public static String getDir(String uuid){ String dir1=Integer.toHexString(uuid.hashCode() & 0xf); String dir2=Integer.toHexString((uuid.hashCode() & 0xf0)>>4); return dir1+\"/\"+dir2; } }
Dom4jFactory(dom4j的相关操作,获取document对象,保存操作)
package cn.hncu.utils; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.UnsupportedEncodingException; import org.dom4j.Document; import org.dom4j.DocumentException; import org.dom4j.io.OutputFormat; import org.dom4j.io.SAXReader; import org.dom4j.io.XMLWriter; public class Dom4jFactory { private static Document dom = null; private static String path; static { try { SAXReader sax = new SAXReader(); // 学习一下服务器下的资源路径加载方式(因为我们的资源已经从MyEclipse中发布到Tomcat服务器中了,所以跟原来纯Java项目不一样了) // 利用当前类找到它的类加载器,然后通过该类加载器再去获得资源路径 path = Dom4jFactory.class.getClassLoader().getResource(\"photos.xml\") .getPath(); dom = sax.read(new FileInputStream(path)); } catch (Exception e) { throw new RuntimeException(e.getMessage(), e); } } public static Document getDom(){ return dom; } public static boolean save(){ try { OutputFormat format=new OutputFormat(); format.setEncoding(\"utf-8\"); XMLWriter w = new XMLWriter( new FileOutputStream(new File(path)),format); w.write(dom); w.close(); return true; } catch (Exception e) { return false; } } }
从底层写PhotoDao
package cn.hncu.dao; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import org.dom4j.Document; import org.dom4j.Element; import cn.hncu.demain.PhotoModel; import cn.hncu.utils.Dom4jFactory; public class PhotoDao { //添加 public boolean add(PhotoModel photo){ Document dom=Dom4jFactory.getDom(); Element root=dom.getRootElement(); Element ePhoto=root.addElement(\"photo\"); ePhoto.addAttribute(\"id\", photo.getId()); ePhoto.addAttribute(\"realName\", photo.getRealName()); ePhoto.addAttribute(\"dir\", photo.getDir()); ePhoto.addAttribute(\"ip\", photo.getIp()); ePhoto.addAttribute(\"dateTime\", photo.getDateTime()); ePhoto.addAttribute(\"ext\", photo.getExt()); ePhoto.addElement(\"desc\").setText(photo.getDesc()); boolean boo=Dom4jFactory.save(); return boo; } //浏览 public List<PhotoModel> getAll(){ Document dom=Dom4jFactory.getDom(); List<PhotoModel> list=new ArrayList<PhotoModel>(); Element root=dom.getRootElement(); Iterator<Element> it=root.elementIterator(); while(it.hasNext()){ PhotoModel photo=new PhotoModel(); Element e=it.next(); photo.setId(e.attributeValue(\"id\")); photo.setDateTime(e.attributeValue(\"dateTime\")); photo.setDir(e.attributeValue(\"dir\")); photo.setExt(e.attributeValue(\"ext\")); photo.setIp(e.attributeValue(\"ip\")); photo.setRealName(e.attributeValue(\"realName\")); photo.setDesc(e.elementText(\"desc\")); list.add(photo); } return list; } public PhotoModel getSingleById(String id) { Document dom=Dom4jFactory.getDom(); List<PhotoModel> list=getAll(); for(PhotoModel photo:list){ if(photo.getId().equals(id)){ return photo; } } return null; } public boolean del(String id) { Document dom=Dom4jFactory.getDom(); Element e=(Element) dom.selectSingleNode(\"//photo[@id=\'\"+id.trim()+\"\']\"); return e.getParent().remove(e); } }
最后写四个servlet
UploadServlet 上传Servlet代码
package cn.hncu.servlets; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; 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.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.apache.commons.io.FileUtils; import cn.hncu.dao.PhotoDao; import cn.hncu.demain.PhotoModel; import cn.hncu.utils.MyUtils; public class UploadServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType(\"text/html;charset=utf-8\"); PrintWriter out = response.getWriter(); out.println(\"<!DOCTYPE HTML PUBLIC \\\"-//W3C//DTD HTML 4.01 Transitional//EN\\\">\"); out.println(\"<HTML>\"); out.println(\" <HEAD><TITLE>A Servlet</TITLE></HEAD>\"); out.println(\" <BODY>\"); out.println(\"不支持get方式上传!\"); out.println(\" </BODY>\"); out.println(\"</HTML>\"); out.flush(); out.close(); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType(\"text/html;charset=utf-8\"); PrintWriter out = response.getWriter(); String path=request.getServletContext().getRealPath(\"/photos\"); DiskFileItemFactory factory=new DiskFileItemFactory(); factory.setRepository(new File(\"g:/a\")); ServletFileUpload upload = new ServletFileUpload(factory); upload.setSizeMax(1024*1024*10);//最大10M upload.setHeaderEncoding(\"utf-8\");//用于设置文件名的编码,相当于:request.setCharacterEncoding(\"utf-8\"); FileItem fi=null; try { List<FileItem> list=upload.parseRequest(request); PhotoModel photo = new PhotoModel();//数据封装---需要7个属性 boolean boo=false; InputStream in = null; for(FileItem fi2:list){ fi=fi2; if(fi.isFormField()){ String desc=fi.getString(\"utf-8\"); photo.setDesc(desc);//desc }else{ in=fi.getInputStream(); String realName=fi.getName(); if(realName==null || realName.trim().equals(\"\")){ out.print(\"没有选择文件!\"); return; } if(realName.indexOf(\"\\\\\")!=-1){ realName=realName.substring(realName.lastIndexOf(\"\\\\\")+1); } photo.setRealName(realName);//真实文件名 String ext=realName.substring(realName.lastIndexOf(\".\")); photo.setExt(ext);//3 photo.setDateTime(MyUtils.getCurrentDateTime());//4 photo.setId(MyUtils.getUUid());//5 photo.setDir(MyUtils.getDir(photo.getId()));//6 photo.setIp(request.getRemoteAddr());//7 } } //把相片信息存储到数据库 PhotoDao dao=new PhotoDao(); boo=dao.add(photo); //如果上面的相片信息保存成功,那么才开始接收图片文件,把它保存到服务器硬盘 if(boo){ System.out.println(dao); path=path+\"/\"+photo.getDir(); File dir=new File(path); if(!dir.exists()){ dir.mkdirs(); } String fileName=path+\"/\"+photo.getId()+photo.getExt(); FileUtils.copyInputStreamToFile(in, new File(fileName)); String strPath = request.getContextPath()+\"/servlets/ShowServlet\"; out.print(\"上传成功!<a href=\'\"+strPath+\"\'>浏览相册</a>\"); }else{ out.print(\"上传失败!\"); } } catch (FileUploadException e) { throw new RuntimeException(\"上传失败!\", e); }finally{ if(fi!=null){ fi.delete(); } } out.flush(); out.close(); } }
ShowServlet 浏览相册的Servlet端
package cn.hncu.servlets; import java.io.IOException; import java.io.PrintWriter; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import cn.hncu.dao.PhotoDao; import cn.hncu.demain.PhotoModel; public class ShowServlet extends HttpServlet { IOException if an error occurred public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType(\"text/html;charset=utf-8\"); request.setCharacterEncoding(\"utf-8\"); PrintWriter out = response.getWriter(); out.println(\"<!DOCTYPE HTML PUBLIC \\\"-//W3C//DTD HTML 4.01 Transitional//EN\\\">\"); out.println(\"<HTML>\"); out.println(\" <HEAD><TITLE>A Servlet</TITLE></HEAD>\"); out.println(\" <BODY>\"); String table=\"<table border=\'1\' width=\'100%\'>\"+ \"<tr><th>文件名</th><th>上传ip</th><th>上传时间</th><th>图片</th><th>说明</th><th>操作</th></tr>\" ; out.print(table); PhotoDao dao=new PhotoDao(); List<PhotoModel> list=dao.getAll(); for(PhotoModel p:list){ out.print(\"<tr>\"); out.println(\"<td>\"+p.getRealName()+\"</td>\"); out.println(\"<td>\"+p.getIp()+\"</td>\"); out.println(\"<td>\"+p.getDateTime()+\"</td>\"); //输出图片 String path=request.getContextPath()+\"/photos/\"+p.getDir()+\"/\"+p.getId()+p.getExt(); out.println(\"<td><a href=\'\"+path+\"\'><img src=\'\"+path+\"\' width=\'200\' height=\'200\'></img></a></td>\"); String op=\"<a href=\'\"+request.getContextPath()+\"/servlets/DelServlet?id=\"+p.getId()+\"\'>删除</a> \"; out.println(\"<td>\"+p.getDesc()+\"</td>\"); op+=\"<a href=\'\"+request.getContextPath()+\"/servlets/DownServlet?id=\"+p.getId()+\"\'>下载</a>\"; out.println(\"<td>\"+op+\"</td>\"); out.print(\"</tr>\"); } out.println(\"</table>\"); out.println(\" </BODY>\"); out.println(\"</HTML>\"); out.flush(); out.close(); } }
DownServlet 下载的服务器代码
package cn.hncu.servlets; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.PrintWriter; import java.net.URLEncoder; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import cn.hncu.dao.PhotoDao; import cn.hncu.demain.PhotoModel; public class DownServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String id=request.getParameter(\"id\"); response.setContentType(\"application/force-download\"); PhotoModel p=new PhotoDao().getSingleById(id); if(p!=null){ String realName=p.getRealName(); realName=new String(realName.getBytes(\"iso8859-1\"),\"utf-8\"); response.setHeader(\"content-Disposition\", \"attachment;filename=\\\"\"+realName+\"\\\"\"); String relpath=getServletContext().getRealPath(\"/photos/\"+p.getDir()+\"/\"+p.getId()+p.getExt()); InputStream in=new FileInputStream(relpath); OutputStream out=response.getOutputStream(); System.out.println(relpath); byte buf[]=new byte[1024]; int len=0; while ((len=in.read(buf))!=-1){ out.write(buf,0,len); } out.close(); }else{ response.setContentType(\"text/html;charset=utf-8\"); response.getWriter().println(\"该文件已经被删除!\"); } } }
Delservlet 删除操作的服务器
package cn.hncu.servlets; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import cn.hncu.dao.PhotoDao; import cn.hncu.demain.PhotoModel; public class DelServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding(\"utf-8\"); response.setContentType(\"text/html;charset=utf-8\"); PrintWriter out=response.getWriter(); String id=request.getParameter(\"id\"); PhotoModel p=new PhotoDao().getSingleById(id); if(p!=null){ if(!p.getIp().equals(request.getRemoteAddr())){ out.println(\"你无权进行删除!\"); return; } //※※※※以下部分课后补敲的!!!! //1删除数据库中的信息 PhotoDao dao=new PhotoDao(); boolean boo=dao.del(id); //2把服务器硬盘中的文件删除 if(boo){ String fileName=\"photos/\"+p.getDir()+\"/\"+p.getId()+p.getExt(); String pathFileName = getServletContext().getRealPath(fileName); File f=new File(pathFileName); if(f.exists()){ f.delete(); } String strPath = request.getContextPath()+\"/servlets/ShowServlet\"; out.println(\"相片删除成功!<a href=\'\"+strPath+\"\'>浏览相册</a>\"); }else{ out.println(\"相片删除失败!\"); } }else{ response.setContentType(\"text/html;charset=utf-8\"); response.getWriter().println(\"该文件不存在!\"); } } }
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