文件4. 获取文件信息
servlet层获取通过文件路径获取文件的相关信息
.jsp界面
1 <form action="<%=basePath %>fileAction" method="get" > 2 <table> 3 <tr> 4 <td>输入文件路径</td> 5 <td><input type="text" name="filePath" /></td> 6 </tr> 7 <tr> 8 <td colspan="2"><input type="submit" value="查看"/></td> 9 </tr> 10 <tr> 11 <td colspan="2">文件属性：</td> 12 </tr> 13 <tr> 14 <td colspan="2"><table id="fileContent"></table></td> 15 </tr> 16 </table> 17 </form> 18
.js界面
1 $("input[name='filePath']").blur(function(){ 2 var val=$("input[name='filePath']").val(); 3 if(val=='') { 4 alert("源文件路径不能为空！"); 5 } else { 6 var data={"method":"getFileInfo","fromPath":val}; 7 var xmlhttp=getXmlhttp(); 8 xmlhttp.onreadystatechange=function() { 9 if(xmlhttp.readyState==4 && xmlhttp.status==200) { 10 var table=$("#fileContent"); 11 table.empty(); 12 var content=""; 13 alert(xmlhttp.responseText); 14 var fileInfo=eval("("+xmlhttp.responseText+")"); 15 for(i in fileInfo) { 16 content+="<tr><td>"+i+"</td><td>"+fileInfo[i]+"</td></tr>"; 17 } 18 table.html(content); 19 } 20 }; 21 xmlhttp.open("POST","fileAction",true); 22 xmlhttp.setRequestHeader("Content-Type","application/json"); 23 xmlhttp.send(JSON.stringify(data)); 24 } 25 });
servlet层FileAction.java
1 protected void doPost(HttpServletRequest req, HttpServletResponse resp) 2 throws ServletException, IOException { 3 req.setCharacterEncoding("utf-8"); 4 resp.setCharacterEncoding("utf-8"); 5 resp.setContentType("text/html;charset=utf-8"); 6 PrintWriter out=resp.getWriter(); 7 // 第一步：解析json字符串得到json对象 8 JSONObject data=this.getJsonObject(req); 9 // 第二步：获取json对象中的键获得值 10 String method=data.getString("method"); 11 if(method.equals("getFileInfo")) { 12 JSONObject message=new JSONObject(); 13 String path=data.getString("fromPath"); 14 File file=new File(path); 15 if(file.exists()) { 16 Map<String,String> fileInfo=new HashMap<String, String>(); 17 if(!file.isFile()) { 18 message.put("message", "该路径不是文件！"); 19 out.write(message.toString()); 20 } else { 21 fileInfo.put("文件名称",file.getName()); 22 fileInfo.put("文件路径",file.getCanonicalPath()); 23 fileInfo.put("上级目录", file.getParentFile().getParent()); 24 fileInfo.put("隐藏", file.isHidden()?"隐藏":"显示"); 25 fileInfo.put("只读属性", file.canWrite()?"可写":"不可写"); 26 fileInfo.put("最后修改日期", new Date(file.lastModified()).toString()); 27 fileInfo.put("文件长度", String.format("%#,.2fk", file.length()/1024.0)); 28 JSONObject jsonFileInfo=JSONObject.fromObject(fileInfo); 29 out.write(jsonFileInfo.toString()); 30 } 31 } else { 32 message.put("message", "该文件不存在"); 33 out.write(message.toString()); 34 } 35 } 36 } 37 38 39 private JSONObject getJsonObject(HttpServletRequest req) { 40 StringBuffer json=new StringBuffer(); 41 String lineString=null; 42 BufferedReader reader; 43 JSONObject data=null; 44 try { 45 reader = req.getReader(); 46 while((lineString=reader.readLine())!=null) { 47 json.append(lineString); 48 } 49 data=JSONObject.fromObject(json.toString()); 50 } catch (IOException e) { 51 e.printStackTrace(); 52 } 53 return data; 54 }
