web配置：

web.xml的所有servlet和filter新增配置項： <async-supported>true</async-supported>

java服務端響應：

HttpServlet實現：

private ExecutorService executorPool=Executors.newFixedThreadPool(20);

protectedvoid doPost(HttpServletRequest request,
			HttpServletResponse response) 
{
AsyncContext ctx=request.startAsync();//開啟非同步處理
ctx.setTimeout(5000);
executorPool.submit(new AsyncRequestDownloadService(faceCloudService,downloadBean,ctx)); // 使用執行緒池控制呼叫
}


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public class AsyncRequestDownloadService implements Runnable{

	private AsyncContext ctx;
	private DownloadBean downloadBean;
	private BusinessService businessService;
	
	public AsyncRequestDownloadService(BusinessService businessService,DownloadBean downloadBean,AsyncContext ctx ){
		super();
		this.businessService=businessService;
		this.ctx = ctx;
		this.downloadBean=downloadBean;
	}
	
	@Override
	public void run() {
		downloadFile(downloadBean,(HttpServletResponse)ctx.getResponse());
		ctx.complete();
	}

	private void downloadFile(DownloadBean downloadBean,HttpServletResponse response) {
		switch (downloadBean.getBusinessType()) {
            // TODO
		}
	}