SpringMVC的文件上传

1.客户端(ajax)

function submitImgSize1Upload(){

    var option={
            type:'POST',
            url:'${pageContext.request.contextPath }/upload/uploadPic.do',
            dataType:'text',
            data:{
                fileName : 'imgSize1File'
            },
            success:function(data){

                //把json格式的字符串转换成json对象
                var jsonObj = $.parseJSON(data);

                //返回服务器图片路径，把图片路径设置给img标签
                $("#imgSize1ImgSrc").attr("src",jsonObj.fullPath);
                //数据库保存相对路径
                $("#imgSize1").val(jsonObj.relativePath);
            }

        };

    $("#itemForm").ajaxSubmit(option);

}
</script>

客户端采用ajaxSubmit的方式上传图片文件。

2. 服务器端

在springmvc.xml中配置

<!-- 文件上传解析器 -->  
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="maxUploadSize" value="10240000"></property>
    </bean>

@Controller
@RequestMapping("/upload")
public class UploadController {

    @RequestMapping("uploadPic")
    public void uploadPic(HttpServletRequest request,String fileName,PrintWriter out){
        //把Request强转成多部件请求对象
        MultipartHttpServletRequest mh = (MultipartHttpServletRequest) request;
        //根据文件名称获取文件对象
        CommonsMultipartFile cm = (CommonsMultipartFile) mh.getFile(fileName);
        //获取文件上传流
        byte[] fbytes = cm.getBytes();

        //文件名称在服务器有可能重复？
        String newFileName="";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmssSSS");
        newFileName = sdf.format(new Date());

        Random r = new Random();

        for(int i =0 ;i<3;i++){
            newFileName=newFileName+r.nextInt(10);
        }

        //获取文件扩展名
        String originalFilename = cm.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //创建jesy服务器，进行跨服务器上传
        Client client = Client.create();
        //把文件关联到远程服务器
        WebResource resource = client.resource(Commons.PIC_HOST+"/upload/"+newFileName+suffix);
        //上传
        resource.put(String.class, fbytes);


        //ajax回调函数需要会写写什么东西？
        //图片需要回显：需要图片完整路径
        //数据库保存图片的相对路径.
        String fullPath = Commons.PIC_HOST+"/upload/"+newFileName+suffix;

        String relativePath="/upload/"+newFileName+suffix;
        //{"":"","":""}
        String result="{\"fullPath\":\""+fullPath+"\",\"relativePath\":\""+relativePath+"\"}";

        out.print(result);

    }

}

2.1 上传过程中需注意两次类型强转

MultipartHttpServletRequest CommonsMultipartFile
代码片段如下：

//把Request强转成多部件请求对象
        MultipartHttpServletRequest mh = (MultipartHttpServletRequest) request;
        //根据文件名称获取文件对象
        CommonsMultipartFile cm = (CommonsMultipartFile) mh.getFile(fileName);
        //获取文件上传流
        byte[] fbytes = cm.getBytes();

2.2 服务器端采用jersey框架实现跨服务器上传

代码片段如下：

        //创建jesy服务器，进行跨服务器上传
        Client client = Client.create();
        //把文件关联到远程服务器
        WebResource resource = client.resource(Commons.PIC_HOST+"/upload/"+newFileName+suffix);
        //上传
        resource.put(String.class, fbytes);