title: getOutputStream() has already been called for this response error
body: <p>Exception :</p>
  
  <pre><code>org.apache.jasper.JasperException: java.lang.IllegalStateException: getOutputStream() has already been called for this response
  org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:584)
  org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:466)
  org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389)
  org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
  javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
  org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
  </code></pre>
  
  <p>root cause :</p>
  
  <pre><code>java.lang.IllegalStateException: getOutputStream() has already been called for this response
  org.apache.catalina.connector.Response.getWriter(Response.java:627)
  org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:215)
  javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:105)
  org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:125)
  org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:118)
  org.apache.jasper.runtime.PageContextImpl.release(PageContextImpl.java:190)
  org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext(JspFactoryImpl.java:123)
  org.apache.jasper.runtime.JspFactoryImpl.releasePageContext(JspFactoryImpl.java:80)
  org.apache.jsp.DownloadResume_jsp._jspService(DownloadResume_jsp.java:91)
  org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
  javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
  org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:433)
  org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389)
  org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
  javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
  org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
  </code></pre>