Java 下载功能怎么实现
程序代码：public String excute() {
String filePath = "D:\\a.txt";// 下载的文件路径
getfileAddress(filePath);
try {
InputStream iso = new FileInputStream(filePath);
HttpServletResponse response = ServletActionContext.getResponse();
System.out.println("downloadForm******* "+response);
// response.reset();//清除缓存
response.setHeader("Content-Disposition","attachment;fileName="+filePath);
response.setContentType("text/html;charset=UTF-8");
ServletOutputStream out = response.getOutputStream();
byte[] content = new byte[1024];
int length =0;
while((length = iso.read(content))!=-1){
out.write(content,0,length);
}
out.write(content);
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
return SUCCESS;
}
上面是我实现txt文件下载的一个方法，用struts2框架，重前台页面触发下载功能，提交Action，到实现方法，但是我现在不能下，报错提示说是
: Exception initializing page context
java.lang.IllegalStateException: Cannot create a session after the response has been committed
at org.apache.catalina.connector.Request.doGetSession(Request.java:2675)
上面这个报错，
HttpServletResponse response = ServletActionContext.getResponse();
这句话也报错，可能是获取不到response，response过期等信息，请问有谁做过前台的，帮忙看下，怎么解决
