| /** |
| * 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.kafka.streams.state.internals; |
| |
| import org.apache.kafka.common.serialization.Serde; |
| import org.apache.kafka.common.utils.Time; |
| import org.apache.kafka.streams.KeyValue; |
| import org.apache.kafka.streams.processor.ProcessorContext; |
| import org.apache.kafka.streams.processor.StateStore; |
| import org.apache.kafka.streams.processor.StateStoreSupplier; |
| import org.apache.kafka.streams.state.KeyValueIterator; |
| import org.apache.kafka.streams.state.KeyValueStore; |
| |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.NavigableMap; |
| import java.util.TreeMap; |
| |
| /** |
| * An in-memory key-value store based on a TreeMap. |
| * |
| * @param <K> The key type |
| * @param <V> The value type |
| * |
| * @see org.apache.kafka.streams.state.Stores#create(String) |
| */ |
| public class InMemoryKeyValueStoreSupplier<K, V> implements StateStoreSupplier { |
| |
| private final String name; |
| private final Time time; |
| private final Serde<K> keySerde; |
| private final Serde<V> valueSerde; |
| |
| public InMemoryKeyValueStoreSupplier(String name, Serde<K> keySerde, Serde<V> valueSerde) { |
| this(name, keySerde, valueSerde, null); |
| } |
| |
| public InMemoryKeyValueStoreSupplier(String name, Serde<K> keySerde, Serde<V> valueSerde, Time time) { |
| this.name = name; |
| this.time = time; |
| this.keySerde = keySerde; |
| this.valueSerde = valueSerde; |
| } |
| |
| public String name() { |
| return name; |
| } |
| |
| public StateStore get() { |
| return new MeteredKeyValueStore<>(new MemoryStore<K, V>(name, keySerde, valueSerde).enableLogging(), "in-memory-state", time); |
| } |
| |
| private static class MemoryStore<K, V> implements KeyValueStore<K, V> { |
| private final String name; |
| private final Serde<K> keySerde; |
| private final Serde<V> valueSerde; |
| private final NavigableMap<K, V> map; |
| |
| public MemoryStore(String name, Serde<K> keySerde, Serde<V> valueSerde) { |
| this.name = name; |
| this.keySerde = keySerde; |
| this.valueSerde = valueSerde; |
| this.map = new TreeMap<>(); |
| } |
| |
| public KeyValueStore<K, V> enableLogging() { |
| return new InMemoryKeyValueLoggedStore<>(this.name, this, keySerde, valueSerde); |
| } |
| |
| @Override |
| public String name() { |
| return this.name; |
| } |
| |
| @Override |
| @SuppressWarnings("unchecked") |
| public void init(ProcessorContext context, StateStore root) { |
| // do nothing |
| } |
| |
| @Override |
| public boolean persistent() { |
| return false; |
| } |
| |
| @Override |
| public V get(K key) { |
| return this.map.get(key); |
| } |
| |
| @Override |
| public void put(K key, V value) { |
| this.map.put(key, value); |
| } |
| |
| @Override |
| public V putIfAbsent(K key, V value) { |
| V originalValue = get(key); |
| if (originalValue == null) { |
| put(key, value); |
| } |
| return originalValue; |
| } |
| |
| @Override |
| public void putAll(List<KeyValue<K, V>> entries) { |
| for (KeyValue<K, V> entry : entries) |
| put(entry.key, entry.value); |
| } |
| |
| @Override |
| public V delete(K key) { |
| return this.map.remove(key); |
| } |
| |
| @Override |
| public KeyValueIterator<K, V> range(K from, K to) { |
| return new MemoryStoreIterator<K, V>(this.map.subMap(from, true, to, false).entrySet().iterator()); |
| } |
| |
| @Override |
| public KeyValueIterator<K, V> all() { |
| return new MemoryStoreIterator<K, V>(this.map.entrySet().iterator()); |
| } |
| |
| @Override |
| public void flush() { |
| // do-nothing since it is in-memory |
| } |
| |
| @Override |
| public void close() { |
| // do-nothing |
| } |
| |
| private static class MemoryStoreIterator<K, V> implements KeyValueIterator<K, V> { |
| private final Iterator<Map.Entry<K, V>> iter; |
| |
| public MemoryStoreIterator(Iterator<Map.Entry<K, V>> iter) { |
| this.iter = iter; |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return iter.hasNext(); |
| } |
| |
| @Override |
| public KeyValue<K, V> next() { |
| Map.Entry<K, V> entry = iter.next(); |
| return new KeyValue<>(entry.getKey(), entry.getValue()); |
| } |
| |
| @Override |
| public void remove() { |
| iter.remove(); |
| } |
| |
| @Override |
| public void close() { |
| } |
| |
| } |
| } |
| } |