001/** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.activemq; 018 019import java.util.List; 020import javax.jms.JMSException; 021import org.apache.activemq.command.MessageDispatch; 022 023public interface MessageDispatchChannel { 024 025 public abstract void enqueue(MessageDispatch message); 026 027 public abstract void enqueueFirst(MessageDispatch message); 028 029 public abstract boolean isEmpty(); 030 031 /** 032 * Used to get an enqueued message. The amount of time this method blocks is 033 * based on the timeout value. - if timeout==-1 then it blocks until a 034 * message is received. - if timeout==0 then it it tries to not block at 035 * all, it returns a message if it is available - if timeout>0 then it 036 * blocks up to timeout amount of time. Expired messages will consumed by 037 * this method. 038 * 039 * @throws JMSException 040 * @return null if we timeout or if the consumer is closed. 041 * @throws InterruptedException 042 */ 043 public abstract MessageDispatch dequeue(long timeout) throws InterruptedException; 044 045 public abstract MessageDispatch dequeueNoWait(); 046 047 public abstract MessageDispatch peek(); 048 049 public abstract void start(); 050 051 public abstract void stop(); 052 053 public abstract void close(); 054 055 public abstract void clear(); 056 057 public abstract boolean isClosed(); 058 059 public abstract int size(); 060 061 public abstract Object getMutex(); 062 063 public abstract boolean isRunning(); 064 065 public abstract List<MessageDispatch> removeAll(); 066 067}