content: /*
   * 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.Comparator;
  import java.util.stream.Stream;
  
  import org.apache.cassandra.config.DatabaseDescriptor;
  
  public class SSTableIdFactory
  {
      public static final SSTableIdFactory instance = new SSTableIdFactory();
  
      /**
       * Constructs the instance of {@link SSTableId} from the given string representation.
       * It finds the right builder by verifying whether the given string is the representation of the related identifier
       * type using {@link SSTableId.Builder#isUniqueIdentifier(String)} method.
       *
       * @throws IllegalArgumentException when the provided string representation does not represent id of any type
       */
      public SSTableId fromString(String str) throws IllegalArgumentException
      {
          return Stream.of(UUIDBasedSSTableId.Builder.instance, SequenceBasedSSTableId.Builder.instance)
                       .filter(b -> b.isUniqueIdentifier(str))
                       .findFirst()
                       .map(b -> b.fromString(str))
                       .orElseThrow(() -> new IllegalArgumentException("String '" + str + "' does not match any SSTable identifier format"));
      }
  
      /**
       * Constructs the instance of {@link SSTableId} from the given bytes.
       * It finds the right builder by verifying whether the given buffer is the representation of the related identifier
       * type using {@link SSTableId.Builder#isUniqueIdentifier(ByteBuffer)} method.
       *
       * The method expects the identifier is encoded in all remaining bytes of the buffer. The method does not move the
       * pointer of the buffer.
       *
       * @throws IllegalArgumentException when the provided binary representation does not represent id of any type
       */
      public SSTableId fromBytes(ByteBuffer bytes)
      {
          return Stream.of(UUIDBasedSSTableId.Builder.instance, SequenceBasedSSTableId.Builder.instance)
                       .filter(b -> b.isUniqueIdentifier(bytes))
                       .findFirst()
                       .map(b -> b.fromBytes(bytes))
                       .orElseThrow(() -> new IllegalArgumentException("Byte buffer of length " + bytes.remaining() + " does not match any SSTable identifier format"));
      }
  
      /**
       * Returns default identifiers builder.
       */
      @SuppressWarnings("unchecked")
      public SSTableId.Builder<SSTableId> defaultBuilder()
      {
          SSTableId.Builder<? extends SSTableId> builder = DatabaseDescriptor.isUUIDSSTableIdentifiersEnabled()
                                                           ? UUIDBasedSSTableId.Builder.instance
                                                           : SequenceBasedSSTableId.Builder.instance;
          return (SSTableId.Builder<SSTableId>) builder;
      }
  
      /**
       * Compare sstable identifiers so that UUID based identifier is always greater than sequence based identifier
       */
      public final static Comparator<SSTableId> COMPARATOR = Comparator.nullsFirst((id1, id2) -> {
          if (id1 instanceof UUIDBasedSSTableId)
          {
              UUIDBasedSSTableId uuidId1 = (UUIDBasedSSTableId) id1;
              return (id2 instanceof UUIDBasedSSTableId) ? uuidId1.compareTo((UUIDBasedSSTableId) id2) : 1;
          }
          else if (id1 instanceof SequenceBasedSSTableId)
          {
              SequenceBasedSSTableId seqId1 = (SequenceBasedSSTableId) id1;
              return (id2 instanceof SequenceBasedSSTableId) ? seqId1.compareTo((SequenceBasedSSTableId) id2) : -1;
          }
          else
          {
              throw new AssertionError("Unsupported comparison between " + id1.getClass().getName() + " and  " + id2.getClass().getName());
          }
      });
  }
  