| /* |
| * 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.flink.cep.nfa; |
| |
| import org.apache.flink.cep.nfa.sharedbuffer.EventId; |
| import org.apache.flink.cep.nfa.sharedbuffer.NodeId; |
| |
| import javax.annotation.Nullable; |
| |
| import java.util.Objects; |
| |
| /** |
| * Helper class which encapsulates the currentStateName of the NFA computation. It points to the current currentStateName, |
| * the previous entry of the pattern, the current version and the starting timestamp |
| * of the overall pattern. |
| */ |
| public class ComputationState { |
| // pointer to the NFA currentStateName of the computation |
| private final String currentStateName; |
| |
| // The current version of the currentStateName to discriminate the valid pattern paths in the SharedBuffer |
| private final DeweyNumber version; |
| |
| // Timestamp of the first element in the pattern |
| private final long startTimestamp; |
| |
| @Nullable |
| private final NodeId previousBufferEntry; |
| |
| @Nullable |
| private final EventId startEventID; |
| |
| private ComputationState( |
| final String currentState, |
| @Nullable final NodeId previousBufferEntry, |
| final DeweyNumber version, |
| @Nullable final EventId startEventID, |
| final long startTimestamp) { |
| this.currentStateName = currentState; |
| this.version = version; |
| this.startTimestamp = startTimestamp; |
| this.previousBufferEntry = previousBufferEntry; |
| this.startEventID = startEventID; |
| } |
| |
| public EventId getStartEventID() { |
| return startEventID; |
| } |
| |
| public NodeId getPreviousBufferEntry() { |
| return previousBufferEntry; |
| } |
| |
| public long getStartTimestamp() { |
| return startTimestamp; |
| } |
| |
| public String getCurrentStateName() { |
| return currentStateName; |
| } |
| |
| public DeweyNumber getVersion() { |
| return version; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj instanceof ComputationState) { |
| ComputationState other = (ComputationState) obj; |
| return Objects.equals(currentStateName, other.currentStateName) && |
| Objects.equals(version, other.version) && |
| startTimestamp == other.startTimestamp && |
| Objects.equals(startEventID, other.startEventID) && |
| Objects.equals(previousBufferEntry, other.previousBufferEntry); |
| } else { |
| return false; |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return "ComputationState{" + |
| "currentStateName='" + currentStateName + '\'' + |
| ", version=" + version + |
| ", startTimestamp=" + startTimestamp + |
| ", previousBufferEntry=" + previousBufferEntry + |
| ", startEventID=" + startEventID + |
| '}'; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(currentStateName, version, startTimestamp, startEventID, previousBufferEntry); |
| } |
| |
| public static ComputationState createStartState(final String state) { |
| return createStartState(state, new DeweyNumber(1)); |
| } |
| |
| public static ComputationState createStartState(final String state, final DeweyNumber version) { |
| return createState(state, null, version, -1L, null); |
| } |
| |
| public static ComputationState createState( |
| final String currentState, |
| final NodeId previousEntry, |
| final DeweyNumber version, |
| final long startTimestamp, |
| final EventId startEventID) { |
| return new ComputationState(currentState, previousEntry, version, startEventID, startTimestamp); |
| } |
| } |