/*
* Copyright (c) 2002-2012 Alibaba Group Holding Limited.
* All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.citrus.util.internal;
import static com.alibaba.citrus.util.StringUtil.*;
import javax.servlet.http.HttpServletRequest;
public class ScreenEventUtil {
static final String SCREEN_EVENT_KEY = "_screen_event_";
/** 取得event名称。 */
public static String getEventName(HttpServletRequest request) {
Object savedEvent = request.getAttribute(SCREEN_EVENT_KEY);
if (savedEvent instanceof String) {
return (String) savedEvent;
}
return null;
}
/** 将event名称保存到request中，以便下次取用。 */
public static void setEventName(HttpServletRequest request, String event) {
event = trimToNull(event);
if (event == null) {
request.removeAttribute(SCREEN_EVENT_KEY);
} else {
request.setAttribute(SCREEN_EVENT_KEY, event);
}
}
}