net.sf.eBus.messages.EReplyInfo Maven / Gradle / Ivy
//
// Copyright 2015, 2016, 2019, 2021 Charles W. Rapp
//
// 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 net.sf.eBus.messages;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* This class-level annotation is required for all classes
* extending {@link ERequestMessage}. This annotation contains
* the {@link EReplyMessage} classes which may be sent in reply
* to this request. The class {@code EReplyMessage} does not
* need to be listed since it that message is allowed for all
* request messages.
*
* This annotation is cumulative from {@link ERequestMessage}
* down through extending request message classes. Since
* {@code ERequestMessage} defines {@code EReplyInfo} to allow
* {@code EReplyMessage} as a reply. This means
* {@code EReplyMessage} may be sent in reply to any request.
*
*
* As of eBus release 5.6.0 this annotation was modified to
* contain two more attributes: {@code mayCancel} and
* {@code cancelRequest}. These attributes are used to mark
* whether a request may be unilaterally canceled by calling
* {@code ERequestFeed.ERequest.close} and, if not, then
* whether request may be canceled using a separate cancel
* request message. The point behind using a cancel request
* message is to allow the replier a chance to reject that cancel
* request.
*
* By default a request may be unilaterally {@code close}ed.
* Otherwise there are two cases for using this annotation:
*
*
* -
* The request may not be canceled at all. In this case set
* the annotation to {@code @EReplyInfo(mayClose = false)}.
* Note that the {@code cancelRequest} is not set.
*
* -
* The request may be canceled using a separate message. Set
* the annotation to
* {@code @EReplyInfo(mayClose = false, cancelRequest = ECancelRequest.class)}.
*
*
*
*
* @author Charles W. Rapp
*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
@Documented
public @interface EReplyInfo
{
/**
* Returns the message classes which may be sent in reply
* to a request message.
* @return reply message classes.
*/
Class[] replyMessageClasses();
/**
* Returns {@code true} if
* {@code ERequestFeed.ERequest.inactivate()} may be used to
* cancel {@link ERequestMessage}. Returns {@code false} if
* {@code inactivate()} may not be used to cancel request.
* {@code false} is generally returned if:
*
* -
* the request processing cannot be stopped once started
* or
*
* -
* replier requires a separate cancel request to
* terminate an active request. This gives the replier
* the option of denying the cancel request. This option
* is not provided by {@code inactivate}.
*
*
*
* Default value is {@code true} which means the request may
* be directly closed.
*
* @return {@code true} if request can be inactivated and
* {@code false} if inactivation is not allowed.
*/
boolean mayClose() default true;
} // end of annotation EReplyInfo