| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.qpid.proton.engine.impl; |
| |
| import org.apache.qpid.proton.engine.Collector; |
| import org.apache.qpid.proton.engine.Event; |
| import org.apache.qpid.proton.engine.EventType; |
| |
| |
| /** |
| * CollectorImpl |
| * |
| */ |
| |
| public class CollectorImpl implements Collector |
| { |
| |
| private EventImpl head; |
| private EventImpl tail; |
| private EventImpl free; |
| |
| public CollectorImpl() |
| {} |
| |
| @Override |
| public Event peek() |
| { |
| return head; |
| } |
| |
| @Override |
| public void pop() |
| { |
| if (head != null) { |
| EventImpl next = head.next; |
| head.next = free; |
| free = head; |
| head.clear(); |
| head = next; |
| } |
| } |
| |
| public EventImpl put(EventType type, Object context) |
| { |
| if (type == null) { |
| throw new IllegalArgumentException("Type cannot be null"); |
| } |
| if (!type.isValid()) { |
| throw new IllegalArgumentException("Cannot put events of type " + type); |
| } |
| if (tail != null && tail.getEventType() == type && |
| tail.getContext() == context) { |
| return null; |
| } |
| |
| EventImpl event; |
| if (free == null) { |
| event = new EventImpl(); |
| } else { |
| event = free; |
| free = free.next; |
| event.next = null; |
| } |
| |
| event.init(type, context); |
| |
| if (head == null) { |
| head = event; |
| tail = event; |
| } else { |
| tail.next = event; |
| tail = event; |
| } |
| |
| return event; |
| } |
| |
| @Override |
| public boolean more() { |
| return head != null && head.next != null; |
| } |
| |
| } |