| /* |
| * 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.rya.streams.api.queries; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.util.Objects; |
| |
| import edu.umd.cs.findbugs.annotations.DefaultAnnotation; |
| import edu.umd.cs.findbugs.annotations.NonNull; |
| |
| /** |
| * An ordered entry within a change log. |
| * </p> |
| * Immutable. |
| * |
| * @param <T> - The type of entry that is in the change log. |
| */ |
| @DefaultAnnotation(NonNull.class) |
| public class ChangeLogEntry<T> { |
| |
| private final long position; |
| private final T entry; |
| |
| /** |
| * Constructs an instance of {@link ChangeLogEntry}. |
| * |
| * @param position - The position of this entry within the change log. |
| * @param entry - The value that is stored at this position within the change log. (not null) |
| */ |
| public ChangeLogEntry(final long position, final T entry) { |
| this.position = position; |
| this.entry = requireNonNull(entry); |
| } |
| |
| /** |
| * @return The position of this entry within the change log. |
| */ |
| public long getPosition() { |
| return position; |
| } |
| |
| /** |
| * @return The value that is stored at this position within the change log. (not null) |
| */ |
| public T getEntry() { |
| return entry; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(position, entry); |
| } |
| |
| @Override |
| public boolean equals(final Object o) { |
| if(o instanceof ChangeLogEntry) { |
| final ChangeLogEntry<T> other = (ChangeLogEntry<T>) o; |
| return position == other.position && |
| Objects.equals(entry, other.entry); |
| } |
| return false; |
| } |
| } |