原生JS上传文件(java)

//fileInfo是文件内容(Base64位的字符串),fileName是文件名称,url是需要上传到的地址
//base64的格式是这样的
//data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAEgAAABIAQMAAABvIyEEAAAABlBMVEUAAABTU1OoaSf
///AAAAAXRSTlMAQObYZgAAAENJREFUeF7tzbEJACEQRNGBLeAasBCza2lLEGx0CxFGG9hBMDDxRy
///72O9FMnIFapGylsu1fgoBdkXfUHLrQgdfrlJN1BdYBjQQm3UAAAAASUVORK5CYII=
public static String uploadFile(String fileInfo,String fileName,String url) throws IOException{
        BufferedOutputStream bos=null;
        if(!EmptyUtils.isEmpty(fileInfo)){
            BASE64Decoder decoder=new BASE64Decoder();
            String suffix=fileInfo.substring(fileInfo.indexOf("/")+1,fileInfo.indexOf(";"));
            fileInfo=fileInfo.substring(fileInfo.indexOf(",")+1);
            byte[] fileBytes=decoder.decodeBuffer(fileInfo);
            String baseUrl=url;
            File file=new File(baseUrl);
            if(!file.exists() && !file.isDirectory())
            {   System.out.println("目录不存在需要创建:"+baseUrl);

                file.mkdir();
            }
            for(int i=0;i<fileBytes.length;i++) {
                if(fileBytes[i]<0) {//调整异常数据
                    fileBytes[i]+=256;
                }
            }
            String relativeUrl=UUID.randomUUID().toString().replace("-", "")+"_"+fileName.substring(0,fileName.lastIndexOf("."))+"."+suffix;
            bos=new BufferedOutputStream(new FileOutputStream(new File(file,relativeUrl)));
            bos.write(fileBytes);
            bos.flush();//这个一定要有,否则上传的文件会出现错误,打不开等
            bos.close();
            return baseUrl+"/"+relativeUrl;
        }
        return "";

    }
简单的利用javajs实现文件上传 package com.fendou.myString; import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.util.Iterator; 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.FileItemFactory; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; public class FileUpload extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { boolean a=ServletFileUpload.isMultipartContent(request); if(a){ FileItemFactory factory=new DiskFileItemFactory(); ServletFileUpload upload=new ServletFileUpload (factory); Iterator items; try{ items=upload.parseRequest (request).iterator(); while(items.hasNext()){ FileItem item=(FileItem) items.next(); if(!item.isFormField()){ String name=item.getName (); String fileName=name.substring(name.lastIndexOf("\\")+1, name.length()); String path=request.getRealPath("file")+File.pathSeparatorChar+fileName; File uploadFile=new File (path); request.getSession ().setAttribute("file", uploadFile); item.write(uploadFile); response.setContentType ("text/html"); response.setCharacterEncoding("utf-8"); PrintWriter out=response.getWriter(); // out.print("<font size='2'> 上传文件为:"+name+"<br>"); // out.print("保存在服务器上 的地址为:"+path+"</font>"); } } }catch(Exception e){ e.printStackTrace(); } } response.sendRedirect("smartupload.jsp"); } }
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值