jsp显示doc,xls,jpg

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%><%@page import="java.util.Map"%><%@page import="java.util.HashMap"%><%@page import="javax.imageio.*" %><%@page import="java.io.*" %><%    String imgpath = request.getContextPath();    //String filename = new String(request.getParameter("file").getBytes("ISO-8859-1"),"UTF-8");    String filename = (String)request.getParameter("file");    String number = (String)request.getParameter("number");    String postfix = (String)request.getParameter("postfix");    //String mc = (String)request.getParameter("mc");    //String mc = new String(request.getParameter("mc").getBytes("ISO-8859-1"),"UTF-8");    String array[] = filename.split("/");    String mc = array[array.length -1];    System.out.println("file---"+filename);    System.out.println("number--"+number);    System.out.println("mc--"+mc);    if (postfix != null && postfix.equals("xls")){        //filename = new String(filename.getBytes("UTF-8"),"GBK");        System.out.println("file---"+filename);        response.setContentType("application/vnd.ms-excel");        File file=new File(filename);        FileInputStream in=new FileInputStream(file);        byte[] buffer=new byte[in.available()];        in.read(buffer);        response.getOutputStream().write(buffer);        response.getOutputStream().flush();    }else if(postfix != null && postfix.equals("doc")){        System.out.println("file---"+filename);        response.reset();        response.setContentType( "application/msword");        File file=new File(filename);        response.setHeader( "Content-Disposition ", "inline;   filename= "+file.getName());        FileInputStream in=new FileInputStream(file);        byte[] buffer=new byte[in.available()];        in.read(buffer);        response.getOutputStream().write(buffer);        response.getOutputStream().flush();    }else if(postfix != null && postfix.equals("jpg")){        //File file = new File(filename);        //InputStream in = new FileInputStream(file);        //BufferedImage bfi = ImageIO.read(in);          //response.reset();//清除buffer         // response.setContentType("image/gif");         // ImageIO.write(bfi, "jpg", response.getOutputStream());          //out.clear();         // out = pageContext.pushBody();     }%><%if (postfix !=null && postfix.equals("jpg")){ %>    <img src="<%=imgpath %>/upload/contract/<%=number%>/<%=mc %>"  alt="上海鲜花港 - 郁金香" /><%} %><script type="text/javascript"></script>