小编ame*_*lla的帖子

当我尝试从响应对象获取ServletOutputStream对象时,我收到了java.lang.IllegalStateException.以下是我的代码:

<%@ page import="java.util.*,java.io.*"%>             

<%
try {
    System.out.print("request came");
    File f = new File ("E:/dd.txt");

    String name = f.getName().substring(f.getName().lastIndexOf("/") + 1,f.getName().length());
    InputStream in = new FileInputStream(f);

    ServletOutputStream outs = response.getOutputStream();

    response.setContentType ("application/txt");
    response.setHeader ("Content-Disposition", "attachment; filename="+f.getName()+"");
    int bit = 256;
    int i = 0;
    try {
        while ((bit) >= 0) {
            bit = in.read();
            outs.write(bit);
        }
    } catch (IOException ioe) {
        ioe.printStackTrace(System.out);
    }
    outs.flush();
    outs.close();
    in.close();         
} catch (Exception ioe) {
    ioe.printStackTrace(System.out);
}
%>

以下是堆栈跟踪:

java.lang.IllegalStateException
   at org.apache.jasper.runtime.ServletResponseWrapperInclude.getOutputStream(ServletResponseWrapperInclude.java:63)
   at org.apache.jsp.html.portlet.vitage.custom.QUADWAVE.Procfiledownloadess1_005f36901_005f48.filedownload.downloadscreen_jsp._jspService(downloadscreen_jsp.java:5 …