struts2 输出流展示图片或xml 备忘
采用非resultType是stream
直接acton方法里面返回return null
struts2
InputStream io = null;try{io = repositoryService.getResourceAsStream(deploymentId,fileName);if(io == null){//Struts2Utils.renderHtml("<html><head></head><body></body></html>");logger.warn("io 为null,"+deploymentId+","+fileName);Struts2Utils.renderText("读取数据为null(deploymentId:"+deploymentId+",fileName:"+fileName+"),该业务未定义工作流或流程图有误!");return ;}if(isImage){//response.setContentType("image/png");response.setContentType("image/x-png");}else{response.setContentType("text/xml");}byte[] buf = new byte[1];int len = 0;OutputStream os = response.getOutputStream();//这个位置很重要,如果有报错一定不能执行到这里while((len = io.read(buf)) != -1){os.write(buf, 0, len);} os.flush();os.close();buf = null;}catch(IOException e){addActionError(e.getMessage());}finally{if (io != null) {try {io.close();} catch ( IOException e ) {e.printStackTrace();}}}