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.bookkeeper.bookie;
  
  import com.google.common.cache.Cache;
  import com.google.common.cache.CacheBuilder;
  import java.io.IOException;
  import java.time.Duration;
  import org.apache.bookkeeper.bookie.LedgerStorage.LedgerDeletionListener;
  import org.apache.bookkeeper.util.collections.ConcurrentLongHashMap;
  
  class HandleFactoryImpl implements HandleFactory, LedgerDeletionListener {
      private final ConcurrentLongHashMap<LedgerDescriptor> ledgers;
      private final ConcurrentLongHashMap<LedgerDescriptor> readOnlyLedgers;
  
      /**
       * Once the ledger was marked "fenced" before, the ledger was accessed by multi clients. One client is calling
       * "delete" now, and other clients may call "write" continuously later. We mark these ledgers can not be written
       * anymore. And maintains the state for 7 days is safety.
       */
      private final Cache<Long, Boolean> recentlyFencedAndDeletedLedgers = CacheBuilder.newBuilder()
              .expireAfterAccess(Duration.ofDays(7)).build();
  
      final LedgerStorage ledgerStorage;
  
      HandleFactoryImpl(LedgerStorage ledgerStorage) {
          this.ledgerStorage = ledgerStorage;
          this.ledgers = ConcurrentLongHashMap.<LedgerDescriptor>newBuilder().build();
          this.readOnlyLedgers = ConcurrentLongHashMap.<LedgerDescriptor>newBuilder().build();
  
          ledgerStorage.registerLedgerDeletionListener(this);
      }
  
      @Override
      public LedgerDescriptor getHandle(final long ledgerId, final byte[] masterKey, boolean journalReplay)
              throws IOException, BookieException {
          LedgerDescriptor handle = ledgers.get(ledgerId);
  
          if (handle == null) {
              if (!journalReplay && recentlyFencedAndDeletedLedgers.getIfPresent(ledgerId) != null) {
                  throw BookieException.create(BookieException.Code.LedgerFencedAndDeletedException);
              }
              handle = LedgerDescriptor.create(masterKey, ledgerId, ledgerStorage);
              ledgers.putIfAbsent(ledgerId, handle);
          }
  
          handle.checkAccess(masterKey);
          return handle;
      }
  
      @Override
      public LedgerDescriptor getReadOnlyHandle(final long ledgerId) throws IOException, Bookie.NoLedgerException {
          LedgerDescriptor handle = readOnlyLedgers.get(ledgerId);
  
          if (handle == null) {
              handle = LedgerDescriptor.createReadOnly(ledgerId, ledgerStorage);
              readOnlyLedgers.putIfAbsent(ledgerId, handle);
          }
  
          return handle;
      }
  
      private void markIfConflictWritingOccurs(long ledgerId) {
          LedgerDescriptor ledgerDescriptor = ledgers.get(ledgerId);
          try {
              if (ledgerDescriptor != null && ledgerDescriptor.isFenced()) {
                  recentlyFencedAndDeletedLedgers.put(ledgerId, true);
              }
          } catch (IOException | BookieException ex) {
              // The ledger is in limbo state.
              recentlyFencedAndDeletedLedgers.put(ledgerId, true);
          }
      }
  
      @Override
      public void ledgerDeleted(long ledgerId) {
          markIfConflictWritingOccurs(ledgerId);
          // Do delete.
          ledgers.remove(ledgerId);
          readOnlyLedgers.remove(ledgerId);
      }
  }
  