| /* |
| * 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.cassandra.io.sstable; |
| |
| import java.nio.ByteBuffer; |
| import java.util.function.Supplier; |
| import java.util.stream.Stream; |
| |
| import org.apache.cassandra.io.util.File; |
| |
| /** |
| * Represents a unique identifier in the sstable descriptor filename. |
| * This ensures each sstable file uniqueness for the certain table on a single node. However, new implementations |
| * should ensure the uniqueness across the entire cluster. The legacy implementation which does not satisfy cluster-wide |
| * uniqueness will be deprecated and eventually removed. |
| * <p> |
| * A new implementation must adhere to the following invariants: |
| * - Must be locally sortable - that is, the comparison must reflect the comparison of generation times of identifiers |
| * generated on the same node |
| * - String representation must *not* include the {@link Descriptor#FILENAME_SEPARATOR} character, see {@link Descriptor#fromFileWithComponent(File)} |
| * - must be case-insensitive because the sstables can be stored on case-insensitive file system |
| * <p> |
| */ |
| public interface SSTableId |
| { |
| /** |
| * Creates a byte format of the identifier that can be parsed by |
| * {@link Builder#fromBytes(ByteBuffer)} |
| */ |
| ByteBuffer asBytes(); |
| |
| /** |
| * Creates a String format of the identifier that can be parsed by |
| * {@link Builder#fromString(String)} |
| * <p> |
| * Must not contain any {@link Descriptor#FILENAME_SEPARATOR} character as it is used in the Descriptor |
| * see {@link Descriptor#fromFileWithComponent(File)} |
| */ |
| @Override |
| String toString(); |
| |
| /** |
| * Builder that can create instances of certain implementation of {@link SSTableId}. |
| */ |
| interface Builder<T extends SSTableId> |
| { |
| /** |
| * Creates a new generator of identifiers. Each supplied value must be different to all the previously generated |
| * values and different to all the provided existing identifiers. |
| */ |
| Supplier<T> generator(Stream<SSTableId> existingIdentifiers); |
| |
| boolean isUniqueIdentifier(String str); |
| |
| boolean isUniqueIdentifier(ByteBuffer bytes); |
| |
| /** |
| * Creates an identifier instance from its string representation |
| * |
| * @param str string representation as returned by {@link SSTableId#toString()} |
| * @throws IllegalArgumentException when the provided string is not a valid string representation of the identifier |
| */ |
| T fromString(String str) throws IllegalArgumentException; |
| |
| /** |
| * Creates an identifier instance from its binary representation |
| * <p> |
| * The method expects the identifier is encoded in all remaining bytes of the buffer. The method does not move the |
| * pointer of the buffer. |
| * |
| * @param bytes binary representation as returned by {@link #asBytes()} |
| * @throws IllegalArgumentException when the provided bytes are not a valid binary representation of the identifier |
| */ |
| T fromBytes(ByteBuffer bytes) throws IllegalArgumentException; |
| } |
| } |