| /* |
| * 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.trie |
| |
| import org.apache.tuweni.bytes.Bytes |
| import org.apache.tuweni.bytes.Bytes32 |
| import org.apache.tuweni.crypto.Hash.keccak256 |
| import org.apache.tuweni.rlp.RLP |
| |
| internal class NullNode<V> private constructor() : Node<V> { |
| |
| companion object { |
| private val RLP_NULL = RLP.encodeByteArray(ByteArray(0)) |
| private val HASH = keccak256(RLP_NULL) |
| private val instance = NullNode<Any>() |
| |
| @Suppress("UNCHECKED_CAST") |
| fun <V> instance(): NullNode<V> = instance as NullNode<V> |
| } |
| |
| override suspend fun accept(visitor: NodeVisitor<V>, path: Bytes): Node<V> = visitor.visit(this, path) |
| |
| override suspend fun path(): Bytes = Bytes.EMPTY |
| |
| override suspend fun value(): V? = null |
| |
| override fun rlp(): Bytes = RLP_NULL |
| |
| override fun rlpRef(): Bytes = RLP_NULL |
| |
| override fun hash(): Bytes32 = HASH |
| |
| override suspend fun replacePath(path: Bytes): Node<V> = this |
| } |