動手寫一個java版簡單云相冊,實現的功能是：
用戶可以一次上傳一個至多個文件。
用戶可以下載其他人上傳的圖片。
用戶可以查看其他所有人的圖片。
用戶只能刪除通過自己IP上傳的圖片。
用到的技術：
文件上傳下載、設計模式、Dom4j、xPath等。
先看下2個頁面：
原始碼:
web.xml:
<?xml version="1.0" encoding="UTF-8"?><web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> <display-name></display-name> <servlet> <servlet-name>UploadServlet</servlet-name> <servlet-class>cn.hncu.servlets.UploadServlet</servlet-class> </servlet> <servlet> <servlet-name>cloudPhotoServlet</servlet-name> <servlet-class>cn.hncu.servlets.cloudPhotoServlet</servlet-class> </servlet> <servlet> <servlet-name>DownServlet</servlet-name> <servlet-class>cn.hncu.servlets.DownServlet</servlet-class> </servlet> <servlet> <servlet-name>DelServlet</servlet-name> <servlet-class>cn.hncu.servlets.DelServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>UploadServlet</servlet-name> <url-pattern>/upload</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>cloudPhotoServlet</servlet-name> <url-pattern>/cloudPhoto</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>DownServlet</servlet-name> <url-pattern>/servlet/DownServlet</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>DelServlet</servlet-name> <url-pattern>/servlet/DelServlet</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app>
index.jsp:
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <title>chx雲相冊</title> <script type="text/javascript"> function delFile(input){ table = input.parentElement.parentElement.parentElement;//table.nodeName TBODY table.removeChild(input.parentElement.parentElement); } var t=1; function addFile(input){ tr = input.parentElement.parentElement; //alert(tr.nodeName); var str = "<td>選擇文件：</td>"+ "<td> <input type='file' name='file"+t+"'> </td> "+ "<td>文件說明：</td>"+ "<td> <input type='text' name='text"+t+"'> </td> "+ "<td> <input type='button' value='刪除文件' onclick='delFile(this)'> </td>"; tr.insertAdjacentHTML("beforeBegin",str); } function move(){ window.location.href="/myPhoto/cloudPhoto"; } </script> <style type="text/css"> #font{ color:red; } </style> </head> <body> <h1><font id="font">相冊上傳：</font></h1> <form action="/myPhoto/upload" method="post" enctype="multipart/form-data"> <table> <tr> <td>選擇文件：</td> <td> <input type="file" name="file1"> </td> <td>文件說明：</td> <td> <input type="text" name="text1"> </td> <td> <input type="button" value="刪除文件" onclick="delFile(this)"> </td> </tr> <tr> <td colspan=2> <input type="submit" value="上傳文件"> </td> <td colspan=3> <input type="button" value="添加文件" onclick="addFile(this)"> </td> </tr> </table> </form> <form action="/myPhoto/cloudPhoto" method="post" enctype="multipart/form-data"> <table> <tr> <td colspan=5><input type="submit" value="進入雲相冊" onclick="move()"></td> </tr> </table> </form> </body></html>photo.xml:
<?xml version="1.0" encoding="UTF-8"?><photos></photos>
MyUtils.java:
package cn.hncu.utils;import java.text.SimpleDateFormat;import java.util.Date;import java.util.UUID;public class MyUtils { /** * @return 獲取UUID */ public static String getUUID(){ return UUID.randomUUID().toString().replace("-", ""); } /** * @param uuid * @return 通過uuid，獲得打散後的路徑*/ public static String getDir(String uuid){ String dir1 = Integer.toHexString( uuid.hashCode() & 0xf ); String dir2 = Integer.toHexString( (uuid.hashCode() & 0xf0)>>4 ); return "/"+dir1+"/"+dir2; } //日期時間格式private static SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日HH:mm:ss"); /** * @return 返回的是上傳的時候的日期時間*/ public static String getCurrentDateTime(){ return sdf.format(new Date()); }}Dom4jFactory.java:
package cn.hncu.utils;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.UnsupportedEncodingException;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.Element;import org.dom4j.Node;import org.dom4j.io.SAXReader;import org.dom4j.io.XMLWriter;public class Dom4jFactory { private static Document dom=null; private static String path; //靜態塊！只會運行一次！特點是在類加載的時候就執行static{ try { SAXReader sax = new SAXReader(); //因為我們的資源已經從myelipse中發佈到tomcat服務器中了，所以跟原來的純Java項目不一樣了。 //利用當前類找到它的類加載器，然後通過該類加載器再去獲得資源路徑path = Dom4jFactory.class.getClassLoader().getResource("photo.xml").getPath(); //getClassLoader()返回：加載此對象所表示的類或接口的類加載器//public URL getResource(String name)返回：讀取資源的URL 對象；如果找不到該資源，或者調用者沒有足夠的權限獲取該資源，則返回null。 //此方法首先搜索資源的父類加載器；如果父類加載器為null，則搜索的路徑就是虛擬機的內置類加載器的路徑。 //public String getPath()獲取此URL 的路徑部分。 System.out.println(path); dom = sax.read(new FileInputStream(path)); } catch (FileNotFoundException e) { throw new RuntimeException(e); } catch (DocumentException e) { throw new RuntimeException(e); } } /** * @return 獲取相冊的Document */ public static Document getDocument(){ return dom; } /** * 進行photo.xml的保存，保存到本地*/ public static boolean save(){ try { XMLWriter w = new XMLWriter(new FileOutputStream(path)); w.write(dom); w.close(); return true; } catch (UnsupportedEncodingException e) { return false; } catch (FileNotFoundException e) { return false; } catch (IOException e) { return false; } } public static boolean del(String uuid){ Node node = dom.selectSingleNode("[@uuid='"+uuid+"']"); if(node==null){ return false; } node.getParent().remove(node); return true; } /** * 測試用* @param args */ public static void main(String[] args){ System.out.println( getDocument() ); }}PhotoModel.java-值對象
package cn.hncu.domain;/** * 值對象封裝* @author 陳浩翔* 2016-7-24 */public class PhotoModel { private String uuid;//uuid private String realName="";//圖片真實文件名(上傳時的文件名) private String ext;//後綴名private String dir;//打散後的路徑private String dateTime;//上傳文件的時間private String ip;//上傳者的IP private String desc;//文件的說明public String getUuid() { return uuid; } public void setUuid(String uuid) { this.uuid = uuid; } 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 [uuid=" + uuid + ", realName=" + realName + ", ext=" + ext + ", dir=" + dir + ", dateTime=" + dateTime + ", ip=" + ip + ", desc=" + desc + "]"; }}PhotoDao.java:
package cn.hncu.photoDao.Dao;import java.util.List;import cn.hncu.domain.PhotoModel;public interface PhotoDao { /** * @param photo * @return 數據的保存*/ public boolean save(PhotoModel photo); /** * @return 返回所所有的圖片信息*/ public List<PhotoModel> getAll(); /** * @param uuid * @return 通過uuid 查找那個被封裝的值對象*/ public PhotoModel getSingleByUuid(String uuid); /** * @param uuid * @return 通過uuid刪除photos.xml中該圖片的信息*/ public boolean deleteXml(String uuid); /** * @param dir * @return 通過路徑刪除服務器磁盤中該圖片的信息*/ public boolean deleteFile(String pathFileName);}PhotoSerImpl.java:
package cn.hncu.photoDao.impl;import java.io.File;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import org.dom4j.Document;import org.dom4j.Element;import org.dom4j.Node;import cn.hncu.domain.PhotoModel;import cn.hncu.photoDao.Dao.PhotoDao;import cn.hncu.utils.Dom4jFactory;public class PhotoSerImpl implements PhotoDao{ @Override public boolean save(PhotoModel photo) { Document dom = Dom4jFactory.getDocument(); Element root = dom.getRootElement(); //添加屬性Element p = root.addElement("photo"); p.addAttribute("uuid", photo.getUuid()); p.addAttribute("realName", photo.getRealName()); p.addAttribute("dateTime", photo.getDateTime()); p.addAttribute("ip", photo.getIp()); p.addAttribute("ext", photo.getExt()); p.addAttribute("dir", photo.getDir()); p.addAttribute("desc", photo.getDesc()); return Dom4jFactory.save(); } @Override public List<PhotoModel> getAll() { List<PhotoModel> list = new ArrayList<PhotoModel>(); Document dom = Dom4jFactory.getDocument(); Element root = dom.getRootElement(); Iterator<Element> it = root.elementIterator("photo"); //通過DOM4J獲得photo元素的迭代器,也可以通過xPath來找到所有的photo //List<Node> lists = dom.selectNodes("//photo[@uuid]"); //Iterator<Node> it = lists.iterator(); while(it.hasNext()){ Element e = it.next(); PhotoModel photo = new PhotoModel(); photo.setUuid(e.attributeValue("uuid")); photo.setRealName(e.attributeValue("realName")); photo.setDateTime(e.attributeValue("dateTime")); photo.setExt(e.attributeValue("ext")); photo.setIp(e.attributeValue("ip")); photo.setDir(e.attributeValue("dir")); photo.setDesc(e.attributeValue("desc")); list.add(photo); } return list; } @Override public PhotoModel getSingleByUuid(String uuid) { List<PhotoModel> photos=getAll(); for(PhotoModel photo:photos){ if(photo.getUuid().equals(uuid)){ return photo; } } return null; } @Override public boolean deleteXml(String uuid) { Document dom = Dom4jFactory.getDocument(); Element e = (Element) dom.selectSingleNode("//photo[@uuid='"+uuid.trim()+"']"); return e.getParent().remove(e); } @Override public boolean deleteFile(String pathFileName) { try { File file = new File(pathFileName); if(file.exists()){ file.delete(); } return true; } catch (Exception e) { return false; } }}PhotoDaoFactory.java:
package cn.hncu.photoDao.factory;import cn.hncu.photoDao.impl.PhotoSerImpl;/** * 工廠方法* @author 陳浩翔* 2016-7-24 */public class PhotoDaoFactory { public static PhotoSerImpl getPhotoDao(){ return new PhotoSerImpl(); }}上傳-UploadServlet.java:
package cn.hncu.servlets;import java.io.File;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 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 cn.hncu.domain.PhotoModel;import cn.hncu.photoDao.Dao.PhotoDao;import cn.hncu.photoDao.factory.PhotoDaoFactory;import cn.hncu.utils.Dom4jFactory;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"); response.getWriter().print("<h1>很抱歉，本頁面不支持GET方式訪問！！！</h1>"); response.getWriter().print("<a href='javascript:history.go(-1)'>返回上一頁</a> "); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); final PrintWriter out = response.getWriter(); //防黑-非multipart表單提交//使用上傳工具的方式boolean boo = ServletFileUpload.isMultipartContent(request); if(!boo){ out.print("<h1>不支持普通表單的提交方式！ </h1>"); return; } File file = new File("d:/photoCache"); if(!file.exists()){ file.mkdir(); } DiskFileItemFactory fiFactory = new DiskFileItemFactory(1024*10,file); ServletFileUpload upload = new ServletFileUpload(fiFactory); upload.setHeaderEncoding("utf-8");//設置文件名編碼String path = getServletContext().getRealPath("/photos"); FileItem fi = null; try { List<FileItem> list = upload.parseRequest(request); PhotoModel photo = new PhotoModel();//數據封裝---需要7個屬性photo.setRealName(""); int cont=0; for(FileItem f:list){ if(cont!=0 && cont%2==0 && !photo.getRealName().equals("")){ photo = new PhotoModel();//重新數據封裝} fi=f; if(fi.isFormField()){//普通表單組件//得到文件說明String desc = fi.getString("utf-8"); photo.setDesc(desc);//#1 }else{ //防黑3-如果在file組件中不選擇文件if(fi.getSize()==0){ photo.setRealName(""); cont++; continue; } String fileName = fi.getName(); fileName = fileName.substring( fileName.lastIndexOf("//")+1);//真實文件名photo.setRealName(fileName);//#2 String ext = fileName.substring(fileName.lastIndexOf("."));//擴展名photo.setExt(ext);//#3 photo.setDateTime(MyUtils.getCurrentDateTime());//#4 photo.setIp( request.getRemoteAddr() );//#5 String uuid = MyUtils.getUUID(); photo.setUuid(uuid);//#6 photo.setDir( MyUtils.getDir(uuid) );//#7 //打散目錄File dFile = new File(path+photo.getDir()); if(!dFile.exists()){ dFile.mkdirs(); } fi.write(new File(path+photo.getDir()+"/"+photo.getUuid()+photo.getExt())); } cont++; if(cont%2==0 && !photo.getRealName().equals("")){ PhotoDao dao = PhotoDaoFactory.getPhotoDao(); boo = dao.save(photo); //存入磁盤-法二：FileUtils.copyInputStreamToFile(in, new File(fileName2));//※2※ 把圖片文件存儲到服務器硬盤photo = new PhotoModel();//重新數據封裝} } } catch (FileUploadException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); }finally{ if(fi!=null){ fi.delete(); } if(Dom4jFactory.save()){ out.print("<h1>上傳成功！ </h1>"); out.print("<a href='javascript:history.go(-1)'>返回上一頁</a> "); }else{ out.print("<h1>上傳失敗！</h1>"); out.print("<a href='javascript:history.go(-1)'>返回上一頁</a> "); } } }}顯示所有文件-cloudPhotoServlet.java
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.domain.PhotoModel;import cn.hncu.photoDao.Dao.PhotoDao;import cn.hncu.photoDao.factory.PhotoDaoFactory;public class cloudPhotoServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String pwd = (String) request.getParameter("pwd"); if ("chx".equals(pwd)) { doPost(request, response); } else { response.setContentType("text/html;charset=utf-8"); response.getWriter().print("<h1>很抱歉，你沒有權限訪問！！！</h1>"); } } public void doPost(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>CHX雲相冊</TITLE></HEAD>"); out.println(" <BODY>"); out.println("<table border='1px;double;#ff0000'>"); out.println("<tr>"); out.println("<td>文件名</td>"); out.println("<td>上傳時間"); out.println("<td>文件</td>"); out.println("<td>文件說明</td>"); out.println("<td>操作</td> "); out.println("</tr>"); String tdWH = "style='width:200px; height:200px;'"; // 顯示所有圖片PhotoDao dao = PhotoDaoFactory.getPhotoDao(); List<PhotoModel> photos = dao.getAll(); for (PhotoModel photo : photos) { String fileName = photo.getRealName(); String time = photo.getDateTime(); // 輸出圖片String path = request.getContextPath() + "/photos/" + photo.getDir() + "/" + photo.getUuid() + photo.getExt(); // System.out.println(path); // /myPhoto/photos//7/c/a1237a48a6aa451cb22fa78b15bafcea.jpg String img = "<a href='" + path + "'><img src='" + path + "'/></a>"; String desc = photo.getDesc(); String delStr = "<a href='/myPhoto/servlet/DelServlet?uuid=" + photo.getUuid() + "'>刪除</a>"; String downStr = "<a href='/myPhoto/servlet/DownServlet?uuid=" + photo.getUuid() + "'>下載</a>"; out.println("<tr>"); out.println("<td " + tdWH + "> " + fileName + " </td>"); out.println("<td " + tdWH + ">" + time + "</td>"); out.println("<td " + tdWH + ">" + img + "</td>"); out.println("<td " + tdWH + ">" + desc + "</td>"); out.println("<td " + tdWH + ">" + delStr + "" + downStr + "</td>"); out.println("</tr>"); } out.println("<tr>"); out.println("</tr>"); out.println("</table>"); out.println(" </BODY>"); out.println("</HTML>"); out.flush(); out.close(); }}刪除文件-DelServlet.java
package cn.hncu.servlets;import java.io.IOException;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.domain.PhotoModel;import cn.hncu.photoDao.Dao.PhotoDao;import cn.hncu.photoDao.factory.PhotoDaoFactory;public class DelServlet extends HttpServlet { //注入private PhotoDao dao = PhotoDaoFactory.getPhotoDao(); public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String uuid = request.getParameter("uuid"); String ip = request.getRemoteAddr(); response.setContentType("text/html;charset=utf-8"); PrintWriter out = response.getWriter(); PhotoModel photo = dao.getSingleByUuid(uuid); if(photo!=null){ if(!photo.getIp().equals(ip)){ out.print("<h1>你沒有權限刪除這個文件！ ！ ！ </h1>"); out.print("<a href='javascript:history.go(-1)'>返回上一頁</a> "); return ; } //1.刪除數據庫中的信息boolean boo = dao.deleteXml(uuid); if(boo){ String fileName = "photos/"+photo.getDir()+"/"+photo.getUuid()+photo.getExt(); String pathFileName = getServletContext().getRealPath(fileName); if(dao.deleteFile(pathFileName)){ //重定向到相冊頁面response.sendRedirect("/myPhoto/cloudPhoto?pwd=chx"); }else{ out.print("<h1>無法從服務器中刪除，文件正在被佔用！！！</h1>"); out.print("<a href='javascript:history.go(-1)'>返回上一頁</a> "); } }else{ out.print("<h1>該文件已經不存在！！！</h1>"); out.print("<a href='javascript:history.go(-1)'>返回上一頁</a> "); } } }}下載文件-DownServlet.java
package cn.hncu.servlets;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;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.domain.PhotoModel;import cn.hncu.photoDao.Dao.PhotoDao;import cn.hncu.photoDao.factory.PhotoDaoFactory;public class DownServlet extends HttpServlet { private PhotoDao dao = PhotoDaoFactory.getPhotoDao(); public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String uuid = request.getParameter("uuid"); System.out.println(uuid); PhotoModel photo = dao.getSingleByUuid(uuid); System.out.println(photo); if(photo!=null){ //設置響應頭--內容接收程序--瀏覽器看到這個響應頭，就會把它認為的下載程序打開//(如果識別迅雷那麼就會自動打開迅雷，如果沒有則會打開一個“文件另存為”的對話框) response.setContentType("application/force-download"); String realName = photo.getRealName(); String agent = request.getHeader("User-Agent"); System.out.println(agent); if(agent.indexOf("Mozilla")!=-1){//火狐瀏覽器response.setHeader("Content-Disposition", "attachment;filename="+ new String(realName.getBytes("GB2312"),"ISO-8859-1")); }else{ //解決中文亂碼問題（只要用下面一句對文件名進行編碼就行了） realName = URLEncoder.encode(realName, "utf-8");//使用指定的編碼機制將字符串轉換為application/x-www-form-urlencoded 格式。 response.setHeader("Content-Disposition", "attachment;filename=/""+realName+"/""); //注意：“cttachment;”不能少，否則瀏覽器會直接在新窗口中打開} String fileName = "photos/" + photo.getDir()+"/"+photo.getUuid()+photo.getExt(); String pathFileName = getServletContext().getRealPath(fileName); InputStream in = new FileInputStream(pathFileName); OutputStream out = response.getOutputStream(); byte buf[] = new byte[2048]; int len=0; while( (len=in.read(buf))!=-1 ){ out.write(buf, 0, len); } out.close(); in.close(); }else{ response.setContentType("text/html;charset=utf-8"); response.getWriter().println("<h1>該文件已經被刪除了</h1>"); } }}演示結果
這個我就不演示啦，圖片在前面也有，所有的源碼我都給了。有興趣的可以自己取改進一下咯。
其實這個還能上傳其他任意類型文件哦，因為我們沒有防護後綴名的，而且我們是用字符流傳輸，全都不會失真(可以當云盤來處理了~~)！ ！
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。