Java实现先把多个文件压缩为zip文件后下载zip文件
Java实现请求后台后,多个Excel压缩成一个zip后,再下载zip,下载完删除压缩包。
1、添加依赖
<!-- 下载依赖 -->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.2</version>
</dependency>
<!-- servlet的依赖,有就不用 -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
2、DownloadZip下载servlet,servlet
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
public class DownloadZip extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setCharacterEncoding("UTF-8");
//获得要下载的文件名
String fileName = "用户表.xlsx";
String fileName2 = "用户表1.xlsx";
String fileSaveRootPath = "F:\\develop_java\\tomcat\\apache-tomcat-9.0.13\\webapps\\ROOT\\WEB-INF\\classes\\excel\\";
//得到要下载的文件
File file = new File(fileSaveRootPath, fileName);
File file2 = new File(fileSaveRootPath, fileName2);
System.out.println("Excel文件保存路径1:" + fileSaveRootPath + fileName);
System.out.println("Excel文件保存路径2:" + fileSaveRootPath + fileName2);
//如果文件不存在
if (!file.exists() || !file2.exists()) {
request.setAttribute("message", "您要下载的资源已被删除!!");
request.getRequestDispatcher("/message.jsp").forward(request, response);
return;
}
//先压缩
String zipName = "下载Excel.zip";
String zipPath = fileSaveRootPath + zipName;
ZipOutputStream zipOutput = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(zipPath)));
ZipEntry zEntry = new ZipEntry(file.getName());
zipOutput.putNextEntry(zEntry);
BufferedInputStream bis = new BufferedInputStream(new FileInputStream(file));
byte[] buffer = new byte[1024];
int read = 0;
while((read = bis.read(buffer)) != -1){
zipOutput.write(buffer, 0, read);
}
zEntry = new ZipEntry(file2.getName());
zipOutput.putNextEntry(zEntry);
bis = new BufferedInputStream(new FileInputStream(file2));
while((read = bis.read(buffer)) != -1){
zipOutput.write(buffer, 0, read);
}
bis.close();
zipOutput.close();
//创建输出流,下载zip
try(OutputStream out = response.getOutputStream();
FileInputStream in = new FileInputStream(new File(zipPath));){
//设置响应头,控制浏览器下载该文件
response.setHeader("Content-Type","application/octet-stream");
response.setHeader("Content-Disposition",
"attachment;filename="+java.net.URLEncoder.encode(zipName, "UTF-8"));
while((read = in.read(buffer)) != -1){
out.write(buffer, 0, read);
}
System.out.println("zip下载路径:"+zipPath);
}finally {
try {
//删除压缩包
File zfile = new File(zipPath);
zfile.delete();
}catch (Exception e){
e.printStackTrace();
}
}
}
}
3、web.xml配置servlet,我这里没有使用框架
<servlet>
<servlet-name>DownloadZip</servlet-name>
<servlet-class>com.gx.zip.DownloadZip</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>DownloadZip</servlet-name>
<url-pattern>/servlet/DownloadZip</url-pattern>
</servlet-mapping>
4、downzip.jsp下载jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>下载zip</title>
</head>
<body>
<a href="${pageContext.request.contextPath}/servlet/DownloadZip">下载</a>
</body>
</html>
5、message.jsp没有文件提示jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
${ message }
</body>
</html>
6、测试
http://localhost:8080/downzip.jsp
OK!Thank you for reading!