SpringMVC文件下载

package com.sniper.springmvc.action;

 

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.UnsupportedEncodingException;

import java.net.URLEncoder;

 

import org.springframework.http.HttpHeaders;

import org.springframework.http.HttpStatus;

import org.springframework.http.ResponseEntity;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.ResponseBody;

 

@Controller

public class FileDownloadAction extends RootAction {

 

    private String getFileName(String filePath)

            throws UnsupportedEncodingException {

        String fileName = filePath.substring(filePath.lastIndexOf("/") + 1);

        String Agent = request.getHeader("User-Agent");

        if (null != Agent) {

            Agent = Agent.toLowerCase();

            if (Agent.indexOf("firefox") != -1) {

                fileName = new String(fileName.getBytes(), "iso8859-1");

            } else if (Agent.indexOf("msie") != -1) {

                fileName = URLEncoder.encode(fileName, "UTF-8");

            } else {

                fileName = URLEncoder.encode(fileName, "UTF-8");

            }

        }

        return fileName;

    }

 

    /**

     * 需要通过 redirect:download 传递文件路径或者文件类型

     *

     * @param path

     * @param type

     * @return

     * @throws IOException

     */

    @ResponseBody

    @RequestMapping(value = "download")

    public ResponseEntity<byte[]> download(

            @RequestParam(value = "path") String path,

            @RequestParam(value = "type", required = false, defaultValue = "application/vnd.ms-excel") String type)

            throws IOException {

        // 确定各个成员变量的值

        String fileName = getFileName(path);

 

        HttpHeaders headers = new HttpHeaders();

        byte[] body = null;

        HttpStatus httpState = HttpStatus.NOT_FOUND;

        File file = new File(path);

        if (file.exists() && file.isFile()) {

 

            InputStream is = new FileInputStream(file);

            body = new byte[is.available()];

            is.read(body);

            is.close();

            headers.add("Content-Type", type);

            headers.add("Content-Length", "" + body.length);

            headers.add("Content-Disposition", "attachment;filename="

                    + fileName);

            httpState = HttpStatus.OK;

 

        }

 

        ResponseEntity<byte[]> entity = new ResponseEntity<>(body, headers,

                httpState);

 

        return entity;

    }

}