| /* |
| * Copyright 2014-present Open Networking Laboratory |
| * |
| * 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 org.onosproject.net.packet; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| |
| /** |
| * Abstraction of an inbound packet processor. |
| */ |
| public interface PacketProcessor { |
| |
| int ADVISOR_MAX = Integer.MAX_VALUE / 3; |
| int DIRECTOR_MAX = (Integer.MAX_VALUE / 3) * 2; |
| int OBSERVER_MAX = Integer.MAX_VALUE; |
| |
| /** |
| * Returns a priority in the ADVISOR range, where processors can take early action and |
| * influence the packet context. However, they cannot handle the packet (i.e. call send() or block()). |
| * The valid range is from 1 to ADVISOR_MAX. |
| * Processors in this range get to see the packet first. |
| * |
| * @param priority priority within ADVISOR range |
| * @return overall priority |
| */ |
| static int advisor(int priority) { |
| int overallPriority = priority + 1; |
| checkArgument(overallPriority > 0 && overallPriority <= ADVISOR_MAX, |
| "Priority not within ADVISOR range"); |
| return overallPriority; |
| } |
| |
| /** |
| * Returns a priority in the DIRECTOR range, where processors can handle the packet. |
| * The valid range is from ADVISOR_MAX+1 to DIRECTOR_MAX. |
| * Processors in this range get to see the packet second, after ADVISORS. |
| * |
| * @param priority priority within the DIRECTOR range |
| * @return overall priority |
| */ |
| static int director(int priority) { |
| int overallPriority = ADVISOR_MAX + priority + 1; |
| checkArgument(overallPriority > ADVISOR_MAX && overallPriority <= DIRECTOR_MAX, |
| "Priority not within DIRECTOR range"); |
| return overallPriority; |
| } |
| |
| /** |
| * Returns a priority in the OBSERVER range, where processors cannot take any action, |
| * but can observe what action has been taken until then. |
| * The valid range is from DIRECTOR_MAX+1 to OBSERVER_MAX. |
| * Processors in this range get to see the packet last, after ADVISORS and DIRECTORS. |
| * |
| * @param priority priority within the OBSERVER range |
| * @return overall priority |
| */ |
| static int observer(int priority) { |
| int overallPriority = DIRECTOR_MAX + priority + 1; |
| checkArgument(overallPriority > DIRECTOR_MAX, |
| "Priority not within OBSERVER range"); |
| return overallPriority; |
| } |
| |
| /** |
| * Processes the inbound packet as specified in the given context. |
| * |
| * @param context packet processing context |
| */ |
| void process(PacketContext context); |
| |
| } |