Bom, no meu ActionForward eu gero um arquivo.xml que é uma string…
depois eu fiz isso…
response.reset();
response.resetBuffer();
response.setBufferSize(1024 * 1024);
response.setContentType ("application/download");
response.setHeader ("Content-Disposition", "attachment; filename=\"" + "arquivo.xml\"");
response.getOutputStream().write(str.getBytes("ISO-8859-1"));
e o erro…
SEVERE: Exception Processing ErrorPage[errorCode=500, location=/plc/erros/erro500.jsp]
java.lang.IllegalStateException: getOutputStream() has already been called for this response
at org.apache.catalina.connector.Response.getWriter(Response.java:596)
at org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:186)
at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:124)
Obrigado!!