求助:通过PrintWriter写的js在关流时出现Stream closed

代码是写在一个jsp页面中的
错误如下：
严重: Servlet.service() for servlet jsp threw exception
java.io.IOException: Stream closed
at org.apache.jasper.runtime.JspWriterImpl.ensureOpen(JspWriterImpl.java:204)
at org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:115)
at org.apache.jasper.runtime.PageContextImpl.release(PageContextImpl.java:188)
at org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext(JspFactoryImpl.java:118)
at org.apache.jasper.runtime.JspFactoryImpl.releasePageContext(JspFactoryImpl.java:77)
at org.apache.jsp.merchant_005fcenter.imgConUpload_jsp._jspService(imgConUpload_jsp.java:102)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
这是代码:没有找到PrintWriter是在哪创建的
<%@ page language="java" import="java.util.*,tom.wuzi.*,java.io.*,java.sql.*,com.jspsmart.upload.File,com.jspsmart.upload.Files,com.jspsmart.upload.Request,com.jspsmart.upload.SmartUpload" pageEncoding="gb2312"%><%
response.setContentType("text/html;charset=gb2312");
request.setCharacterEncoding("gb2312");
String merchant_id=(String)session.getAttribute("merchant_id");
try {
int count = Integer.parseInt(request.getParameter("count"));
String imgs = request.getParameter("imgs");
String[] img = imgs.split("@");
for(int i=1;i<count;i++){String imgtop = request.getParameter("imgtop"+i);
String describe = request.getParameter("describe"+i);
Connection conn;
Statement sql;
String update="";
conn=DBToolsX.getConnection();
sql=conn.createStatement();
update="UPDATE Image_Url SET imgtop='"+imgtop+"',describe='"+describe+"' where userid='"+merchant_id+"' and imgurl='"+img[i]+"'";
sql.executeUpdate(update);
}
out.println("<SCRIPT LANGUAGE=javascript>");
out.println("alert('保存成功！');");
out.println("window.location.href='rahmenList.jsp'; ");
out.println("</script>");
out.flush();
out.close();
}catch(SQLException s){
 s.printStackTrace();
}%>
如果不关流的话，网页不自动弹出成功提示，只有再点一下页面才会弹出“保存成功”