文件流接口和下载

时间 2019-11-17

标签文件接口下载繁體版

原文原文链接

java文件流接口javascript

package com.rainmanqqst.controller.filestream;

import com.Ostermiller.util.Base64;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;

/**
 * @author RAINMANQQST
 * @date 2019-07-15 14:52
 * @description
 */
@RestController
@RequestMapping("/fille")
public class FileController {

    private static Logger logger = LoggerFactory.getLogger(FileController.class);

    /**
     * 将直接资源请求接口地址转为文件流接口
     * filePath为base64加密的文件地址
     * @param filePath
     * @param request
     * @param response
     */
    @RequestMapping(value="/resource/{filePath}")
    public void achieveResource(@PathVariable("filePath") String filePath, HttpServletRequest request, HttpServletResponse response){
        try {
            String path = Base64.decode(filePath);
            logger.info("resource path is "+path);

            File file = new File(filePath);
            logger.info("fileName : "+file.getName());

            response.setHeader("Content-disposition", "attachment; filename="+file.getName());
            response.setContentType("application/octet-stream;charset=UTF-8");
            response.setHeader("Content-Length",file.length()+"");

            InputStream inputStream = new FileInputStream(file);
            ServletOutputStream servletOutputStream = response.getOutputStream();
            int len = 0;
            byte[] buffer = new byte[1024];
            while((len=inputStream.read(buffer))>0){
                servletOutputStream.write(buffer, 0, len);
            }
            servletOutputStream.flush();
            inputStream.close();
            servletOutputStream.close();
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

}

JS下载代码html

<html>
<head>
    <%--<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">--%>
    <script type="text/javascript">
        function exportFile() {    // name=文件名, blob=文件二进制对象
            //  获取时间戳
            var timestamp=new Date().getTime();
            // 获取XMLHttpRequest
            var xmlResquest = new XMLHttpRequest();
            //  发起请求
            xmlResquest.open("POST", "http://localhost:8086/rainmanqqst/api/system/resource/aHR0cHM6Ly9pbWcxLmRvdWJhbmlvLmNvbS92aWV3L3Bob3RvL2wvcHVibGljL3AxNDIyMDcxNjA4LndlYnA=", true);
            // 设置请求头类型
            xmlResquest.setRequestHeader("Content-type", "application/json");
            //  设置请求token
            //xmlResquest.setRequestHeader(
            //    "Authorization",
            //    Vue.cookie.get('token')
            //);
            xmlResquest.responseType = "blob";
            //  返回
            xmlResquest.onload = function(oEvent) {
                var content = xmlResquest.response;
                alert(content);
                // 组装a标签
                var elink = document.createElement("a");
                // 设置下载文件名
                elink.download = timestamp + ".png";
                elink.style.display = "none";
                var blob = new Blob([content]);
                elink.href = URL.createObjectURL(blob);
                document.body.appendChild(elink);
                elink.click();
                document.body.removeChild(elink);
            };
            xmlResquest.send();
        }


    </script>
</head>

<body>
<input onclick="javascript:exportFile()" type="button" value="test" >
</body>
</html>