怎么会出现这个问题

doPay(AbstractPayAction.java:248) ERROR - verifyTransaction
java.lang.RuntimeException: java.io.IOException: Stream closed
	at org.nutz.lang.Lang.wrapThrow(Lang.java:149)
	at org.nutz.lang.Streams.readAndClose(Streams.java:291)
	at org.nutz.http.Response.getContent(Response.java:148)
	at org.nutz.http.Response.getContent(Response.java:141)
	at com.app.module.pay.AbstractPayAction.verifyResponse(AbstractPayAction.java:178)
	at com.app.module.pay.AbstractPayAction.doPayOrder2AppServer(AbstractPayAction.java:100)
	at com.app.module.pay.AbstractPayAction.doPay(AbstractPayAction.java:220)

调用的方法

public AjaxReturn verifyResponse(Request request, VerifyResponseCallback callback) throws HttpException {
		try {
			Response resp = Sender.create(request).send();
			String result = resp.getContent();
			AjaxReturn jsonBean = callback.invoke(result);
			return jsonBean;
		} catch (HttpException e) {
			throw e;
		}
	}

出错的代码行是

String result = resp.getContent();