Servlet 下载文件 servlet下载文件download手机浏览器android
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2024-02-24 18:50:10
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项目中使用struts2 下载文件,使用手机浏览器有问题,老是报
java.lang.IllegalStateException: Cannot call sendError() after the response has been committed
没办法了,就使用servlet下载apk文件。
servlet类如下:
package com.shop.jn.web.servlet; import java.io.File; import java.io.IOException; import java.io.OutputStream; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang.StringUtils; import com.common.util.SystemUtil; import com.io.hw.file.util.FileUtils; /** * download apk */ public class DownloadServlet extends HttpServlet { private static final long serialVersionUID = 1L; public DownloadServlet() { super(); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { OutputStream out = response.getOutputStream(); // must be linux path(not \\) String filepath = request.getParameter("filepa"); if (StringUtils.isEmpty(filepath)) { filepath = "D:\\eclipse\\workspace\\apkmarket\\upload\\mpc.apk"; } File file = new File(filepath); response.addHeader("Content-Disposition", "attachment;filename=" + SystemUtil.getFileSimpleName(filepath)); response.setContentType("application/octet-stream"); byte[] bytes = FileUtils.readBytes4file(file); System.out.println("size:" + bytes.length); response.addHeader("Content-Length", "" + bytes.length); out.write(bytes); return; } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }
使用servlet之后,手机浏览器仍然有问题,后来发现是因为路径分隔符的问题。
上述servlet需要一个请求要素,就是文件路径。
手机浏览器中,点击一个超链接就开始下载,超链接形如download.do?filepath=D:\eclipse\workspace\apkmarket\upload\mpc.apk
这时,就会下载失败,经过反复测试、尝试,发现路径分隔符有问题,改为:download.do?filepath=D:/eclipse/workspace/apkmarket/upload/mpc.apk 就好了。
说明:手机是安卓系统。
注意:
(1)安卓手机浏览器下载文件时,下载的超链接中文件路径应该使用linux的格式(xxx/xxx/xxx/);
(2)下载servlet中要指定ContentType 为"application/octet-stream"