Aaron Kruglikov | 92511f2 | 2015-10-12 14:39:04 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 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.persistence.impl; |
| 18 | |
| 19 | import com.google.common.collect.Maps; |
| 20 | import com.google.common.collect.Sets; |
| 21 | import org.mapdb.DB; |
| 22 | import org.mapdb.Hasher; |
| 23 | import org.onosproject.store.service.Serializer; |
| 24 | |
| 25 | import java.util.Collection; |
| 26 | import java.util.Map; |
| 27 | import java.util.Set; |
| 28 | |
| 29 | import static com.google.common.base.Preconditions.checkNotNull; |
| 30 | |
| 31 | |
| 32 | /** |
| 33 | * A map implementation that stores and receives all data from a serialized internal map. |
| 34 | */ |
| 35 | public class PersistentMap<K, V> implements Map<K, V> { |
| 36 | |
| 37 | private final Serializer serializer; |
| 38 | |
| 39 | private final org.mapdb.DB database; |
| 40 | |
| 41 | private final Map<byte[], byte[]> items; |
| 42 | |
| 43 | private final String name; |
| 44 | |
| 45 | public PersistentMap(Serializer serializer, DB database, String name) { |
| 46 | this.serializer = checkNotNull(serializer); |
| 47 | this.database = checkNotNull(database); |
| 48 | this.name = checkNotNull(name); |
| 49 | |
| 50 | items = database |
| 51 | .createHashMap(name) |
| 52 | .keySerializer(org.mapdb.Serializer.BYTE_ARRAY) |
| 53 | .valueSerializer(org.mapdb.Serializer.BYTE_ARRAY) |
| 54 | .hasher(Hasher.BYTE_ARRAY) |
| 55 | .makeOrGet(); |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * Reads this set in deserialized form into the provided map. |
| 60 | * |
| 61 | * @param items the map to be populated |
| 62 | */ |
| 63 | public void readInto(Map<K, V> items) { |
| 64 | this.items.forEach((keyBytes, valueBytes) -> |
| 65 | items.put(serializer.decode(keyBytes), |
| 66 | serializer.decode(valueBytes))); |
| 67 | } |
| 68 | |
| 69 | @Override |
| 70 | public V remove(Object key) { |
| 71 | checkNotNull(key, "Key can not be null."); |
| 72 | V removed = get(key); |
| 73 | items.remove(serializer.encode(key)); |
| 74 | return removed; |
| 75 | } |
| 76 | |
| 77 | @Override |
| 78 | public int size() { |
| 79 | return items.size(); |
| 80 | } |
| 81 | |
| 82 | @Override |
| 83 | public boolean isEmpty() { |
| 84 | return items.isEmpty(); |
| 85 | } |
| 86 | |
| 87 | @Override |
| 88 | public boolean containsKey(Object key) { |
| 89 | checkNotNull(key, "Key cannot be null."); |
| 90 | return items.containsKey(serializer.encode(key)); |
| 91 | } |
| 92 | |
| 93 | @Override |
| 94 | public boolean containsValue(Object value) { |
| 95 | checkNotNull(value, "Value cannot be null."); |
| 96 | byte[] serialized = serializer.encode(value); |
| 97 | for (byte[] compareValue : items.values()) { |
| 98 | boolean same = true; |
| 99 | if (compareValue == null) { |
| 100 | same = false; |
| 101 | } else if (compareValue.length != serialized.length) { |
| 102 | same = false; |
| 103 | } else { |
| 104 | for (int i = 0; i < serialized.length; i++) { |
| 105 | if (serialized[i] != compareValue[i]) { |
| 106 | same = false; |
| 107 | break; |
| 108 | } |
| 109 | } |
| 110 | } |
| 111 | if (same) { |
| 112 | return true; |
| 113 | } |
| 114 | } |
| 115 | return false; |
| 116 | } |
| 117 | |
| 118 | @Override |
| 119 | public V get(Object key) { |
| 120 | checkNotNull(key, "Key cannot be null."); |
| 121 | return serializer.decode(items.get(serializer.encode(key))); |
| 122 | } |
| 123 | |
| 124 | @Override |
| 125 | public V put(K key, V value) { |
| 126 | checkNotNull(key, "Key cannot be null."); |
| 127 | checkNotNull(value, "Value cannot be null."); |
| 128 | byte[] prevVal = items.put(serializer.encode(key), serializer.encode(value)); |
| 129 | if (prevVal == null) { |
| 130 | return null; |
| 131 | } |
| 132 | return serializer.decode(prevVal); |
| 133 | } |
| 134 | |
| 135 | @Override |
| 136 | public void putAll(Map<? extends K, ? extends V> m) { |
| 137 | checkNotNull(m, "The passed in map cannot be null."); |
| 138 | m.forEach((k, v) -> items.put(serializer.encode(k), serializer.encode(v))); |
| 139 | } |
| 140 | |
| 141 | @Override |
| 142 | public void clear() { |
| 143 | items.clear(); |
| 144 | } |
| 145 | |
| 146 | @Override |
| 147 | public Set<K> keySet() { |
| 148 | Set<K> keys = Sets.newHashSet(); |
| 149 | items.keySet().forEach(k -> keys.add(serializer.decode(k))); |
| 150 | return keys; |
| 151 | } |
| 152 | |
| 153 | @Override |
| 154 | public Collection<V> values() { |
| 155 | Collection<V> values = Sets.newHashSet(); |
| 156 | items.values().forEach(v -> values.add(serializer.decode(v))); |
| 157 | return values; |
| 158 | } |
| 159 | |
| 160 | @Override |
| 161 | public Set<Entry<K, V>> entrySet() { |
| 162 | Set<Entry<K, V>> entries = Sets.newHashSet(); |
| 163 | items.entrySet(). |
| 164 | forEach(e -> entries.add(Maps.immutableEntry(serializer.decode(e.getKey()), |
| 165 | serializer.decode(e.getValue())))); |
| 166 | return entries; |
| 167 | } |
| 168 | |
| 169 | @Override |
| 170 | public boolean equals(Object map) { |
| 171 | //This is not threadsafe and on larger maps incurs a significant processing cost |
| 172 | if (!(map instanceof Map)) { |
| 173 | return false; |
| 174 | } |
| 175 | Map asMap = (Map) map; |
| 176 | if (this.size() != asMap.size()) { |
| 177 | return false; |
| 178 | } |
| 179 | for (Entry entry : this.entrySet()) { |
| 180 | Object key = entry.getKey(); |
| 181 | if (!asMap.containsKey(key) || !asMap.get(key).equals(entry.getValue())) { |
| 182 | return false; |
| 183 | } |
| 184 | } |
| 185 | return true; |
| 186 | } |
| 187 | |
| 188 | @Override |
| 189 | public int hashCode() { |
| 190 | return super.hashCode(); |
| 191 | } |
| 192 | } |