servlet实现文件下载
2015-08-17 09:58
330 查看
之前没怎么用过这个,这次项目中用到了,于是总结一下:
应该说主要注意三方面:
1、写一个servlet
2、在web.xml中配置这个servlet
3、页面上调用这个servlet
第一:
写一个servlet,当然要继承javax.servlet.http.HttpServlet,重写post或者get方法(看需要),这个servlet的思想就是将要下载的文件写到文件流中去,而这个文件输出流就是HttpServletResponse对象的输出流,如下所示:
public class DownloadServlet extends HttpServlet{
public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException
{
try
{
String downFilename=request.getParameter("curfile");
String filepath=request.getParameter("path");
response.setContentType("text/plain");
response.setHeader("Location",downFilename);
response.setHeader("Content-Disposition", "attachment; filename=" + downFilename);
OutputStream outputStream = response.getOutputStream();
InputStream inputStream = new FileInputStream(filepath+downFilename);
byte[] buffer = new byte[1024];
int i = -1;
while ((i = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, i);
}
outputStream.flush();
outputStream.close();
}catch(FileNotFoundException e1)
{
System.out.println("没有找到您要的文件");
}
catch(Exception e)
{
System.out.println("系统错误,请及时与管理员联系");
}
}
public void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException
{
doPost(request,response);
}
}
web.xml配置:
<servlet>
<servlet-name>download</servlet-name>
<servlet-class>com.dichain.common.tools.DownloadServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>download</servlet-name>
<url-pattern>/Download</url-pattern>
</servlet-mapping>
jsp中调用servlet弹出一个下载对话框:
window.open ('Download?curfile='+curfile+'&path='+path,'newwindow','height=30,width=40,top='+yy+',left='+xx+',toolbar=no,menubar=no,scrollbars=no, resizable=no,location=no, status=no');
应该说主要注意三方面:
1、写一个servlet
2、在web.xml中配置这个servlet
3、页面上调用这个servlet
第一:
写一个servlet,当然要继承javax.servlet.http.HttpServlet,重写post或者get方法(看需要),这个servlet的思想就是将要下载的文件写到文件流中去,而这个文件输出流就是HttpServletResponse对象的输出流,如下所示:
public class DownloadServlet extends HttpServlet{
public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException
{
try
{
String downFilename=request.getParameter("curfile");
String filepath=request.getParameter("path");
response.setContentType("text/plain");
response.setHeader("Location",downFilename);
response.setHeader("Content-Disposition", "attachment; filename=" + downFilename);
OutputStream outputStream = response.getOutputStream();
InputStream inputStream = new FileInputStream(filepath+downFilename);
byte[] buffer = new byte[1024];
int i = -1;
while ((i = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, i);
}
outputStream.flush();
outputStream.close();
}catch(FileNotFoundException e1)
{
System.out.println("没有找到您要的文件");
}
catch(Exception e)
{
System.out.println("系统错误,请及时与管理员联系");
}
}
public void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException
{
doPost(request,response);
}
}
web.xml配置:
<servlet>
<servlet-name>download</servlet-name>
<servlet-class>com.dichain.common.tools.DownloadServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>download</servlet-name>
<url-pattern>/Download</url-pattern>
</servlet-mapping>
jsp中调用servlet弹出一个下载对话框:
window.open ('Download?curfile='+curfile+'&path='+path,'newwindow','height=30,width=40,top='+yy+',left='+xx+',toolbar=no,menubar=no,scrollbars=no, resizable=no,location=no, status=no');
相关文章推荐
- WebSocket
- 读取input:file的路径并显示本地图片的方法
- jQuery 文档操作 - append() 方法
- xml 转义特殊字符 如&'" .
- 余佳文道歉 是谁在炒作这团“泡沫”?
- UIButton 点击热区的扩大
- logstash 向elasticsearch写入数据,如何指定多个数据template
- IntelliJ IDEA自用快捷键(使用defeat修改)
- Linux/Unix time时间戳的处理转换函数
- Android中多个Actvity之间传值实现
- 【HDU4336】【Card Collector】【概率dp】
- 在 Windows 下远程桌面连接 Linux - XManager 篇
- xargs的一些小感悟
- [Java]Contains Duplicate 包含重复数字
- Unity5 如何做资源管理和增量更新
- track by与普通in循环区别
- 真的不能这么堕落了
- window下的homestead部署
- DBNULL与null的区别
- iOS 9之WatchKit for WatchOS 2