ratpack.exec.SuccessPromise Maven / Gradle / Ivy
/*
* Copyright 2014 the original author or authors.
*
* 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 ratpack.exec;
import ratpack.api.NonBlocking;
import ratpack.func.Action;
/**
* A promise of a successful outcome.
*
* Ratpack promises are not fully featured A+ promises.
* They are designed to be low level and adapted to more fully features asynchronous composition libraries (like RxJava, for which there is a Ratpack extension library).
*
* Ratpack promises are not thread safe.
* Instances should not be used concurrently.
*
* Async operations will typically return the subclass of the {@link SuccessPromise}, the {@link Promise} which allows an error handling strategy to be specified.
*
* @param the type of the outcome object
*/
public interface SuccessPromise {
/**
* Specifies what should be done with the promised object when it is ready.
*
* @param then the action to forward the promised object on to
*/
@NonBlocking
void then(Action then);
}