| /* |
| * Copyright 2016-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.store.service; |
| |
| import java.util.Map; |
| import java.util.concurrent.CompletableFuture; |
| |
| import javax.annotation.concurrent.NotThreadSafe; |
| |
| /** |
| * A hierarchical <a href="https://en.wikipedia.org/wiki/Document_Object_Model">document tree</a> data structure. |
| * |
| * @param <V> document tree value type |
| */ |
| @NotThreadSafe |
| public interface AsyncDocumentTree<V> extends DistributedPrimitive { |
| |
| /** |
| * Returns the {@link DocumentPath path} to root of the tree. |
| * |
| * @return path to root of the tree |
| */ |
| DocumentPath root(); |
| |
| /** |
| * Returns the children of node at specified path in the form of a mapping from child name to child value. |
| * |
| * @param path path to the node |
| * @return future for mapping from child name to child value |
| * @throws NoSuchDocumentPathException if the path does not point to a valid node |
| */ |
| CompletableFuture<Map<String, Versioned<V>>> getChildren(DocumentPath path); |
| |
| /** |
| * Returns the value of the tree node at specified path. |
| * |
| * @param path path to the node |
| * @return future that will be either be completed with node's {@link Versioned versioned} value |
| * or {@code null} if path does not point to a valid node |
| */ |
| CompletableFuture<Versioned<V>> get(DocumentPath path); |
| |
| /** |
| * Creates or updates a document tree node. |
| * |
| * @param path path to the node |
| * @param value value to be associated with the node ({@code null} is a valid value) |
| * @return future that will either be completed with the previous {@link Versioned versioned} |
| * value or {@code null} if there was no node previously at that path. |
| * Future will be completed with a {@code IllegalDocumentModificationException} |
| * if the parent node (for the node to create/update) does not exist |
| */ |
| CompletableFuture<Versioned<V>> set(DocumentPath path, V value); |
| |
| /** |
| * Creates a document tree node if one does not exist already. |
| * |
| * @param path path to the node |
| * @param value the non-null value to be associated with the node |
| * @return future that is completed with {@code true} if the new node was successfully |
| * created. Future will be completed with {@code false} if a node already exists at the specified path. |
| * Future will be completed exceptionally with a {@code IllegalDocumentModificationException} if the parent |
| * node (for the node to create) does not exist |
| */ |
| CompletableFuture<Boolean> create(DocumentPath path, V value); |
| |
| /** |
| * Creates a document tree node recursively by creating all missing intermediate nodes in the path. |
| * |
| * @param path path to the node |
| * @param value value to be associated with the node ({@code null} is a valid value) |
| * @return future that is completed with {@code true} if the new node was successfully |
| * created. Future will be completed with {@code false} if a node already exists at the specified path |
| */ |
| CompletableFuture<Boolean> createRecursive(DocumentPath path, V value); |
| |
| /** |
| * Conditionally updates a tree node if the current version matches a specified version. |
| * |
| * @param path path to the node |
| * @param newValue value to associate with the node ({@code null} is a valid value) |
| * @param version current version of the node for update to occur |
| * @return future that is either completed with {@code true} if the update was made |
| * or {@code false} if update did not happen |
| */ |
| CompletableFuture<Boolean> replace(DocumentPath path, V newValue, long version); |
| |
| /** |
| * Conditionally updates a tree node if the current node value matches a specified version. |
| * |
| * @param path path to the node |
| * @param newValue value to associate with the node ({@code null} is a valid value) |
| * @param currentValue current value of the node for update to occur |
| * @return future that is either completed with {@code true} if the update was made |
| * or {@code false} if update did not happen |
| */ |
| CompletableFuture<Boolean> replace(DocumentPath path, V newValue, V currentValue); |
| |
| /** |
| * Removes the node with the specified path. |
| * |
| * @param path path to the node |
| * @return future for the previous value. Future will be completed with a |
| * {@code IllegalDocumentModificationException} if the node to be removed is either the root |
| * node or has one or more children. Future will be completed with a |
| * {@code NoSuchDocumentPathException} if the node to be removed does not exist |
| */ |
| CompletableFuture<Versioned<V>> removeNode(DocumentPath path); |
| |
| /** |
| * Registers a listener to be notified when the subtree rooted at the specified path |
| * is modified. |
| * |
| * @param path path to the node |
| * @param listener listener to be notified |
| * @return a future that is completed when the operation completes |
| */ |
| CompletableFuture<Void> addListener(DocumentPath path, DocumentTreeListener<V> listener); |
| |
| /** |
| * Unregisters a previously added listener. |
| * |
| * @param listener listener to unregister |
| * @return a future that is completed when the operation completes |
| */ |
| CompletableFuture<Void> removeListener(DocumentTreeListener<V> listener); |
| |
| /** |
| * Registers a listener to be notified when the tree is modified. |
| * |
| * @param listener listener to be notified |
| * @return a future that is completed when the operation completes |
| */ |
| default CompletableFuture<Void> addListener(DocumentTreeListener<V> listener) { |
| return addListener(root(), listener); |
| } |
| } |