| /* |
| * 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.tuweni.kv |
| |
| import kotlinx.coroutines.CoroutineDispatcher |
| import kotlinx.coroutines.Dispatchers |
| import kotlinx.coroutines.withContext |
| import org.apache.tuweni.bytes.Bytes |
| import org.mapdb.DB |
| import org.mapdb.DBMaker |
| import org.mapdb.DataInput2 |
| import org.mapdb.DataOutput2 |
| import org.mapdb.HTreeMap |
| import java.io.IOException |
| import java.nio.file.Files |
| import java.nio.file.Path |
| |
| /** |
| * A key-value store backed by a MapDB instance. |
| * |
| * @param dbPath The path to the MapDB database. |
| * @param dispatcher The co-routine dispatcher for blocking tasks. |
| * @return A key-value store. |
| * @throws IOException If an I/O error occurs. |
| * @constructor Open a MapDB-backed key-value store. |
| */ |
| class MapDBKeyValueStore |
| @Throws(IOException::class) |
| constructor( |
| dbPath: Path, |
| private val dispatcher: CoroutineDispatcher = Dispatchers.IO |
| ) : KeyValueStore { |
| |
| companion object { |
| /** |
| * Open a MapDB-backed key-value store. |
| * |
| * @param dbPath The path to the MapDB database. |
| * @return A key-value store. |
| * @throws IOException If an I/O error occurs. |
| */ |
| @JvmStatic |
| @Throws(IOException::class) |
| fun open(dbPath: Path) = MapDBKeyValueStore(dbPath) |
| } |
| |
| private val db: DB |
| private val storageData: HTreeMap<Bytes, Bytes> |
| |
| init { |
| Files.createDirectories(dbPath.parent) |
| db = DBMaker.fileDB(dbPath.toFile()).transactionEnable().closeOnJvmShutdown().make() |
| storageData = db.hashMap( |
| "storageData", |
| BytesSerializer(), |
| BytesSerializer() |
| ).createOrOpen() |
| } |
| |
| override suspend fun get(key: Bytes): Bytes? = withContext(dispatcher) { |
| storageData[key] |
| } |
| |
| override suspend fun put(key: Bytes, value: Bytes) = withContext(dispatcher) { |
| storageData[key] = value |
| db.commit() |
| } |
| |
| /** |
| * Closes the underlying MapDB instance. |
| */ |
| override fun close() = db.close() |
| } |
| |
| private class BytesSerializer : org.mapdb.Serializer<Bytes> { |
| |
| override fun serialize(out: DataOutput2, value: Bytes) { |
| out.packInt(value.size()) |
| out.write(value.toArrayUnsafe()) |
| } |
| |
| override fun deserialize(input: DataInput2, available: Int): Bytes { |
| val size = input.unpackInt() |
| val bytes = ByteArray(size) |
| input.readFully(bytes) |
| return Bytes.wrap(bytes) |
| } |
| } |