文件上传

jsp页面

<ul id="attach_upload_list" style="max-height:150px; overflow-y:auto;"></ul>
</div>
</div>
</td>
<td style="text-align: right;">

<div id="attachContractDlgForm_btnUpload" />
</td>
</tr>

js(基于Extjs的文件上传)

//获取文件名
var getFileName = function(str){
      var reg = /[^\/]*[\/]+/g;
      var str = str.replace(reg, '');
      return str;
};

//文件上传
var uploadFile = function(fileName){
    Ext.Ajax.service({
        url : SERVICE.UPLOAD_FILE_URL,
        jsonData : {},
        success : function(jsonSrc){
            var data = jsonSrc.getData();
                if(data.retCode == '-1') {
                    Ext.MessageBox.alert("提示", "添加附件失败，原因：" + data.msg);
                } else {
                    var attachDTO = data.dto;
                    addAttachMap(attachDTO);
                    appendAttachLink(attachDTO);
                }
                   fileField.reset();
            },
            failure : function(jsonSrc) {
                Ext.MessageBox.alert("提示", "添加附件失败，原因：" + jsonSrc.getMessage());
            },
            params :{
                fileName : fileName,
                attachType : attachTypeCombox.getValue()
            },
            form : "attachContractDlgForm",
            isUpload : true
        });
    };

//添加map
    var addAttachMap = function(attachDTO){
        var key = attachDTO.fileId;
        attachMap.add(key, attachDTO);
    };
    
     //添加附件列表节点
    var appendAttachLink = function (attachDTO) {
        var fileSize = attachDTO.fileSize;
        var tpl = new Ext.Template(
                '<li fileId="{fileId}">',
                '<span >' + attachDTO.fileName + ' (' + fileSize + ')' + '</span>',
                '<a href="#" class="del-link">删除 </a>',
                '</li>');
        tpl.append('attach_upload_list', attachDTO);
        Ext.select("#attach_upload_list li[fileId=" + attachDTO.fileId
             + "] > a.del-link").on("click", delAttachEvent);
        Ext.get("attach_upload_list").addClass(uploadBorderCls);
    };

struts2中的Action代码：
        byte[] fileByteData = null;
        InputStream in = null;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        try {
            in = attachFileInfo.getInputStream();
            byte[] buff = new byte[1024]; 
            int len = 0;
            while((len = in.read(buff, 0 ,100)) != -1){
                out.write(buff, 0, len);
            }
            fileByteData = out.toByteArray();  //获取内存缓冲中的数据
        } catch (Exception e) {
            map.put("retCode", "-1");
            map.put("msg", e.getMessage());
            e.printStackTrace();
            return map;
        }finally{
            if(out != null){
                try {
                        out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(in != null){
                try {
                    in.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        FileOutputStream fos = null;
        BufferedOutputStream bos = null;
        try {
            //根据文名，获取文件的格式

String fileName = dto.getFileName();
int index = fileName.lastIndexOf(".");
if(index > 0){
String fileType = fileName.substring(index+1);
dto.setFileFormat(fileType);
}

            //设置文件的大小
            Double fileSizeKB = fileSize / 1024.0;
            DecimalFormat df = new DecimalFormat("########0.00");    //格式化数据
            String fileSizeStr = df.format(fileSizeKB);
            dto.setFileSize(fileSizeStr + "KB");

Date today = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd");
String todayStr = dateFormat.format(today);
//设置当前日期为相对路径
dto.setRelUrl(todayStr);

            DmStdTrInstrAttachDTO tempDTO = dmStdTrInstrAttachCtrl.addContractDmAttachMgr(sessionId, dto);

//获取文件保存路径
String path = this.getSysPath(sessionId);
String fileFullPath = path + todayStr + "/" + tempDTO.getFileName();

            File file = new File(fileFullPath);
            //文件不存在就创建文件
            if(file!= null && !file.exists()){
                new File(file.getParent()).mkdirs();
                file.createNewFile();
            }
            fos = new FileOutputStream(file);
            bos = new BufferedOutputStream(fos);
            //向文件写入数据
            bos.write(fileByteData);
            bos.close();
            fos.close();
            return tempDTO;
        } catch (Exception e) {
            e.printStackTrace();
            throw new ShineException(e.getMessage());
        }finally{
            if(fos != null)
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            if(bos != null)
                try {
                    bos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
        }