文件下载(使用springmvc框架中ResponseEntity对象)
package com.atguigu.test; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import javax.servlet.http.HttpSession; import org.springframework.http.HttpHeaders; import org.springframework.http.HttpStatus; import org.springframework.http.ResponseEntity; import org.springframework.stereotype.Controller; import org.springframework.util.MultiValueMap; import org.springframework.web.bind.annotation.RequestMapping; @Controller public class UploadAndDown { @RequestMapping("/down") public ResponseEntity<byte[]> down(HttpSession session) throws Exception{ //获取下载文件的路径 (获取tomcat服务器的位置) String realPath = session.getServletContext().getRealPath("img"); String finalPath = realPath+ File.separator +"1.jpg"; //创建字节输入流 InputStream in = new FileInputStream(finalPath); //available():获取输入流所读取的文件的最大字节数 byte[] body = new byte[in.available()]; //把字节读取到数组中 in.read(body); //设置请求头 MultiValueMap<String, String> headers = new HttpHeaders(); headers.add("Content-Disposition", "attachment;filename=aaa.jpg"); //设置响应状态 HttpStatus statusCode = HttpStatus.OK; in.close(); ResponseEntity<byte[]> entity = new ResponseEntity<byte[]>(body, headers, statusCode); return entity; } }