NbpQueueDrain.java

/**
 * Copyright 2016 Netflix, Inc.
 * 
 * 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 io.reactivex.internal.util;

import io.reactivex.Observer;

public interface NbpQueueDrain<T, U> {
    
    boolean cancelled();
    
    boolean done();
    
    Throwable error();
    
    boolean enter();
    
    /**
     * Adds m to the wip counter.
     * @param m the value to add
     * @return the wip value after adding the value
     */
    int leave(int m);
    
    /**
     * Accept the value and return true if forwarded.
     * @param a the subscriber to deliver values to
     * @param v the value to deliver
     */
    void accept(Observer<? super U> a, T v);
}