Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2016-present Open Networking Laboratory |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package org.onosproject.store.primitives.resources.impl; |
| 18 | |
| 19 | import java.util.Iterator; |
| 20 | import java.util.Map; |
| 21 | import java.util.Objects; |
Madan Jampani | 79924fa | 2016-09-13 13:57:03 -0700 | [diff] [blame^] | 22 | import java.util.concurrent.atomic.AtomicLong; |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 23 | |
| 24 | import org.onosproject.store.service.DocumentPath; |
| 25 | import org.onosproject.store.service.DocumentTree; |
| 26 | import org.onosproject.store.service.DocumentTreeListener; |
| 27 | import org.onosproject.store.service.DocumentTreeNode; |
| 28 | import org.onosproject.store.service.IllegalDocumentModificationException; |
| 29 | import org.onosproject.store.service.NoSuchDocumentPathException; |
| 30 | import org.onosproject.store.service.Versioned; |
| 31 | |
| 32 | import com.google.common.base.Preconditions; |
Madan Jampani | 79924fa | 2016-09-13 13:57:03 -0700 | [diff] [blame^] | 33 | import com.google.common.base.Supplier; |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 34 | import com.google.common.collect.Maps; |
| 35 | |
| 36 | /** |
| 37 | * Simple implementation of a {@link DocumentTree}. |
| 38 | * |
| 39 | * @param <V> tree node value type |
| 40 | */ |
| 41 | public class DefaultDocumentTree<V> implements DocumentTree<V> { |
| 42 | |
| 43 | private static final DocumentPath ROOT_PATH = DocumentPath.from("root"); |
| 44 | private final DefaultDocumentTreeNode<V> root; |
Madan Jampani | 79924fa | 2016-09-13 13:57:03 -0700 | [diff] [blame^] | 45 | private final Supplier<Long> versionSupplier; |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 46 | |
| 47 | public DefaultDocumentTree() { |
Madan Jampani | 79924fa | 2016-09-13 13:57:03 -0700 | [diff] [blame^] | 48 | AtomicLong versionCounter = new AtomicLong(0); |
| 49 | versionSupplier = versionCounter::incrementAndGet; |
| 50 | root = new DefaultDocumentTreeNode<V>(ROOT_PATH, null, versionSupplier.get(), null); |
| 51 | } |
| 52 | |
| 53 | public DefaultDocumentTree(Supplier<Long> versionSupplier) { |
| 54 | root = new DefaultDocumentTreeNode<V>(ROOT_PATH, null, versionSupplier.get(), null); |
| 55 | this.versionSupplier = versionSupplier; |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 56 | } |
| 57 | |
| 58 | @Override |
| 59 | public DocumentPath root() { |
| 60 | return ROOT_PATH; |
| 61 | } |
| 62 | |
| 63 | @Override |
| 64 | public Map<String, Versioned<V>> getChildren(DocumentPath path) { |
| 65 | DocumentTreeNode<V> node = getNode(path); |
| 66 | if (node != null) { |
| 67 | Map<String, Versioned<V>> childrenValues = Maps.newHashMap(); |
| 68 | node.children().forEachRemaining(n -> childrenValues.put(simpleName(n.path()), n.value())); |
| 69 | return childrenValues; |
| 70 | } |
| 71 | throw new NoSuchDocumentPathException(); |
| 72 | } |
| 73 | |
| 74 | @Override |
| 75 | public Versioned<V> get(DocumentPath path) { |
| 76 | DocumentTreeNode<V> currentNode = getNode(path); |
| 77 | return currentNode != null ? currentNode.value() : null; |
| 78 | } |
| 79 | |
| 80 | @Override |
| 81 | public Versioned<V> set(DocumentPath path, V value) { |
| 82 | checkRootModification(path); |
| 83 | DefaultDocumentTreeNode<V> node = getNode(path); |
| 84 | if (node != null) { |
Madan Jampani | 79924fa | 2016-09-13 13:57:03 -0700 | [diff] [blame^] | 85 | return node.update(value, versionSupplier.get()); |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 86 | } else { |
| 87 | create(path, value); |
| 88 | return null; |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | @Override |
| 93 | public boolean create(DocumentPath path, V value) { |
| 94 | checkRootModification(path); |
| 95 | DocumentTreeNode<V> node = getNode(path); |
| 96 | if (node != null) { |
| 97 | return false; |
| 98 | } |
| 99 | DocumentPath parentPath = path.parent(); |
| 100 | DefaultDocumentTreeNode<V> parentNode = getNode(parentPath); |
| 101 | if (parentNode == null) { |
| 102 | throw new IllegalDocumentModificationException(); |
| 103 | } |
Madan Jampani | 79924fa | 2016-09-13 13:57:03 -0700 | [diff] [blame^] | 104 | parentNode.addChild(simpleName(path), value, versionSupplier.get()); |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 105 | return true; |
| 106 | } |
| 107 | |
| 108 | @Override |
| 109 | public boolean replace(DocumentPath path, V newValue, long version) { |
| 110 | checkRootModification(path); |
| 111 | DocumentTreeNode<V> node = getNode(path); |
| 112 | if (node != null && node.value() != null && node.value().version() == version) { |
| 113 | if (!Objects.equals(newValue, node.value().value())) { |
| 114 | set(path, newValue); |
| 115 | return true; |
| 116 | } |
| 117 | } |
| 118 | return false; |
| 119 | } |
| 120 | |
| 121 | @Override |
| 122 | public boolean replace(DocumentPath path, V newValue, V currentValue) { |
| 123 | checkRootModification(path); |
| 124 | if (Objects.equals(newValue, currentValue)) { |
| 125 | return false; |
| 126 | } |
| 127 | DocumentTreeNode<V> node = getNode(path); |
| 128 | if (node != null && Objects.equals(Versioned.valueOrNull(node.value()), currentValue)) { |
| 129 | set(path, newValue); |
| 130 | return true; |
| 131 | } |
| 132 | return false; |
| 133 | } |
| 134 | |
| 135 | @Override |
| 136 | public Versioned<V> removeNode(DocumentPath path) { |
| 137 | checkRootModification(path); |
| 138 | DefaultDocumentTreeNode<V> nodeToRemove = getNode(path); |
| 139 | if (nodeToRemove == null) { |
| 140 | throw new NoSuchDocumentPathException(); |
| 141 | } |
| 142 | if (nodeToRemove.hasChildren()) { |
| 143 | throw new IllegalDocumentModificationException(); |
| 144 | } |
| 145 | DefaultDocumentTreeNode<V> parent = (DefaultDocumentTreeNode<V>) nodeToRemove.parent(); |
| 146 | parent.removeChild(simpleName(path)); |
| 147 | return nodeToRemove.value(); |
| 148 | } |
| 149 | |
| 150 | @Override |
| 151 | public void addListener(DocumentPath path, DocumentTreeListener<V> listener) { |
| 152 | // TODO Auto-generated method stub |
| 153 | } |
| 154 | |
| 155 | @Override |
| 156 | public void removeListener(DocumentTreeListener<V> listener) { |
| 157 | // TODO Auto-generated method stub |
| 158 | } |
| 159 | |
| 160 | private DefaultDocumentTreeNode<V> getNode(DocumentPath path) { |
| 161 | Iterator<String> pathElements = path.pathElements().iterator(); |
| 162 | DefaultDocumentTreeNode<V> currentNode = root; |
| 163 | Preconditions.checkState("root".equals(pathElements.next()), "Path should start with root"); |
| 164 | while (pathElements.hasNext() && currentNode != null) { |
| 165 | currentNode = (DefaultDocumentTreeNode<V>) currentNode.child(pathElements.next()); |
| 166 | } |
| 167 | return currentNode; |
| 168 | } |
| 169 | |
Madan Jampani | ad5b8c7 | 2016-09-12 15:05:01 -0700 | [diff] [blame] | 170 | private String simpleName(DocumentPath path) { |
| 171 | return path.pathElements().get(path.pathElements().size() - 1); |
| 172 | } |
| 173 | |
| 174 | private void checkRootModification(DocumentPath path) { |
| 175 | if (ROOT_PATH.equals(path)) { |
| 176 | throw new IllegalDocumentModificationException(); |
| 177 | } |
| 178 | } |
| 179 | } |