用http组件下载中文名称附件报错！

<%@page import="java.net.HttpURLConnection"%>
<%@page import= "java.io.*"%>
<%@page import="java.net.MalformedURLException"%>;
<%@page import="java.net.URL"%>
<%@page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%><%  
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("gbk");
String sysurl =request.getParameter("dizhi");
String sysfilename =request.getParameter("LcUpFileName");
//sysfilename = new String(sysfilename.getBytes("iso-8859-1"),"utf-8");
sysurl ="http://localhost:8085/upfile/"+sysfilename;
sysurl=new String(sysurl.getBytes("iso-8859-1"),"utf-8");
System.out.println("文件名是："+sysurl);

response.reset(); 
response.setContentType("application/x-msdownload"); 
response.setHeader("Content-Disposition","attachment; filename="+java.net.URLEncoder.encode(sysfilename,"gbk"));
BufferedInputStream bis = null;
BufferedOutputStream bos = null;
javax.servlet.ServletOutputStream outStrenam = response.getOutputStream();   
URL url = new URL(sysurl);
HttpURLConnection httpUrl =(HttpURLConnection)url.openConnection();
   
InputStream in =httpUrl.getInputStream();

try
{
bis = new BufferedInputStream(in);
bos = new BufferedOutputStream(outStrenam);
byte buff[] = new byte[2048];
int bytesRead;
while(-1 != (bytesRead = bis.read(buff, 0, buff.length))) 
bos.write(buff, 0, bytesRead);
}
catch(MalformedURLException e)
{
System.out.println("MalformedURLException.");
throw e;
}
catch(IOException e)
{
System.out.println("IOException999999999999999");
throw e;
}
finally
{
if(bis != null)
bis.close();
if(bos != null)
bos.close();
}
out.clear();
        out = pageContext.pushBody();
%>上面是jsp页面代码
异常信息：严重: Servlet.service() for servlet jsp threw exception
java.io.FileNotFoundException: http://localhost:8085/upfile/Bug流程图.doc
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1239)
at org.apache.jsp.jsp.DownLoad_jsp._jspService(DownLoad_jsp.java:82)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:384)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:228)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Thread.java:619)各种编码我都试过了，谁能帮解决下，感激不尽啊。。