高手帮个忙

<%@   page contentType="text/html;charset=utf8"%>
<%@   page import="java.sql.*"%>
<%@   page import="java.util.*"%>
<%@   page import="java.text.*"%>
<%@   page import="java.io.*"%>
<%@   page import="java.awt.*"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head></head>
<body>
<%
   Class.forName("com.mysql.jdbc.Driver").newInstance();
   String url="jdbc:mysql://localhost:3306/customer" +
"?useUnicode=true&characterEncoding=utf8";
   Connection   con   =   DriverManager.getConnection(url,"root","1234");
   String   sql   =   "select   *   from  Picture where id=1";
   Statement stmt = con.createStatement();

   ResultSet rs = stmt.executeQuery(sql);
   if(rs.next()) {

    InputStream in = rs.getBinaryStream("picName");
    ServletOutputStream op = response.getOutputStream();
    int len;
    byte[] buf=new byte[1024];
    while((len= in.read(buf))!=-1) {
     op.write(buf, 0, len);
    }
    op.close();
    in.close();
   }

   rs.close();
   stmt.close();
    con.close();
  %>
</body>
</html>

在数据库中读取图片显示在jsp页面中，但是只显示了图片的名字，并抛出异常

Servlet.service() for servlet jsp threw exception
java.lang.IllegalStateException: getOutputStream() has already been called for this response
at org.apache.catalina.connector.Response.getWriter(Response.java:610)
at org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:198)
at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:125) --------------------编程问答-------------------- getOutputStream() has already been called for this response --------------------编程问答-------------------- out.clear();
out = pageContext.pushBody();  不报错了，单jsp界面只显示图片的名称啊，我要的是显示图片，帮个忙

补充：Java ,  Web 开发