java上传文件

jsp页面

form中的enctype属性应设置为：multipart/form-data

<form action="/uplode.do" method="post" enctype="multipart/form-data">
<td>
　　<input type="file" id="file" name="file" value="file" onchange="fz();"/>                                                                
　　<input type="hidden" id="filepath" name="attachment.filepath" value="$attachment.filepath"/> 
　　<input type="hidden" id="filename" name="attachment.filename" value="$attachment.filename"/> 
　　<input type="hidden" id="suffix" name="attachment.suffix" value="$attachment.suffix"/>   
</td>
</form>

  function fz(){
       var aa=document.getElementById("file").value;
       var arrS2=aa.split("\");
       var i=arrS2.length;
       var filename = arrS2[i-1]
       var arrb = aa.split(".");
       var j = arrb.length;
       document.getElementById("file").value=aa;
       document.getElementById("filename").value=filename;
       document.getElementById("filepath").value="/uploadfiles/casus/"+filename;   
       document.getElementById("suffix").value=arrb[j-1];
    }

action:

     //附件相关
    private AttachmentMatters  attachment;
    private String   fileName; //名字
    private String suffix; //后缀
    private String  file; 
    private String attachmentid;

   /**
    * 上传   */
    public void uploadFile(){ 
        try{
            String name = attachment.getFilename();
            upload(this.file,name) ; //上传到服务器　    
             
　　　　　　  //保存到附件表里      

            if(name!=null&&!name.equals("")){
                attachment.setFilepath("uploadfiles/sss/"+name);   
                attachment.setUploadDate(new Date()); 
                bean.saveObject(attachment);                
            }                                        
           }catch(Exception e){
            e.printStackTrace();
         }  
    } 

public static void upload(String file, String name){ 
        if(file !=null){             
            FileOutputStream outputStream; 
            try { 
                String path=ServletActionContext.getRequest().getRealPath("/uploadfiles/matters");
                String path1=path;
                path1.replaceAll("\u002E\u002E", "2");                
                String fileDir = path+File.separator; 
                String filePath=fileDir+name; 
                
                File f=new File(fileDir); 
                f.mkdirs();                 
                outputStream = new FileOutputStream(filePath); 
                FileInputStream fileIn = new FileInputStream(file); 
                byte[] buffer = new byte[128]; 
                int len; 
                while ((len = fileIn.read(buffer))>0){ 
                    outputStream.write(buffer, 0, len); 
                } 
                fileIn.close(); 
                outputStream.close(); 
            }catch (Exception e) { 
                e.printStackTrace(); 
            } 
        }else{ 
          System.out.println("文件为空"); 
        } 
    }