java将文件转成流文件返回给前端

环境：jdk1.8，springboot2.5.3,项目端口号：9100

1.待转换的文件

一、路径

二、文件内容

2.controller中代码

package com.example.pdf.controller;import com.example.pdf.service.GetFileStreamService;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;/*** @author * @date 2024/3/29 16:28* @describe*/
@RestController
@RequestMapping(value = "test")
public class GetFileStreamController {@Resourceprivate GetFileStreamService getFileStreamService;/*** 获取文件流*/@GetMapping("getFileStream")public void getFileStream(HttpServletResponse response) {getFileStreamService.getFileStream(response);}}

3.service中代码

package com.example.pdf.service;import javax.servlet.http.HttpServletResponse;/*** @author * @date 2024/3/29 16:30* @describe*/
public interface GetFileStreamService {/*** 获取文件流* @param response*/void getFileStream(HttpServletResponse response);
}

4.实现类代码

package com.example.pdf.service.impl;import com.example.pdf.service.GetFileStreamService;
import org.springframework.stereotype.Service;import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;/*** @author* @date 2024/3/29 16:31* @describe*/
@Service
public class GetFileStreamServiceImpl implements GetFileStreamService {/*** 获取文件流*/@Overridepublic void getFileStream(HttpServletResponse response) {// 指定文件路径，获取file文件File file = new File("E:\\Desktop\\temps\\test.pdf");try {// 将文件转为文件输入流FileInputStream fileInputStream = new FileInputStream(file);// 获取响应的输出流OutputStream outputStream = response.getOutputStream();// 将文件转成字节数组，再将数组写入响应的输出流byte[] buffer = new byte[1024];int bytesRead = -1;while ((bytesRead = fileInputStream.read(buffer)) != -1) {outputStream.write(buffer, 0, bytesRead);}// 刷新输出流outputStream.flush();// 关闭流fileInputStream.close();outputStream.close();} catch (Exception e) {e.printStackTrace();}}
}

5.postman中访问结果示例

6.浏览器中访问结果示例