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.client.impl;
  
  import static com.google.common.base.Preconditions.checkArgument;
  import static com.google.common.base.Preconditions.checkNotNull;
  
  import io.netty.util.Recycler;
  import java.util.Iterator;
  import java.util.List;
  import org.apache.bookkeeper.client.api.LedgerEntries;
  import org.apache.bookkeeper.client.api.LedgerEntry;
  
  /**
   * Ledger entries implementation. It is a simple wrap of a list of ledger entries.
   */
  public class LedgerEntriesImpl implements LedgerEntries {
      private List<LedgerEntry> entries;
      private final Recycler.Handle<LedgerEntriesImpl> recyclerHandle;
  
      private LedgerEntriesImpl(Recycler.Handle<LedgerEntriesImpl> recyclerHandle) {
          this.recyclerHandle = recyclerHandle;
      }
  
      private static final Recycler<LedgerEntriesImpl> RECYCLER = new Recycler<LedgerEntriesImpl>() {
          @Override
          protected LedgerEntriesImpl newObject(Recycler.Handle<LedgerEntriesImpl> handle) {
              return new LedgerEntriesImpl(handle);
          }
      };
  
      private void recycle() {
          releaseByteBuf();
          recyclerHandle.recycle(this);
      }
  
      private void releaseByteBuf() {
          if (entries != null) {
              entries.forEach(LedgerEntry::close);
              entries.clear();
              entries = null;
          }
      }
  
      /**
       * Create ledger entries.
       *
       * @param entries the entries with ordering
       * @return the LedgerEntriesImpl
       */
      public static LedgerEntriesImpl create(List<LedgerEntry> entries) {
          checkArgument(!entries.isEmpty(), "entries for create should not be empty.");
          LedgerEntriesImpl ledgerEntries = RECYCLER.get();
          ledgerEntries.entries = entries;
          return ledgerEntries;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public LedgerEntry getEntry(long entryId) {
          checkNotNull(entries, "entries has been recycled");
          long firstId = entries.get(0).getEntryId();
          long lastId = entries.get(entries.size() - 1).getEntryId();
          if (entryId < firstId || entryId > lastId) {
              throw new IndexOutOfBoundsException("required index: " + entryId
                  + " is out of bounds: [ " + firstId + ", " + lastId + " ].");
          }
          return entries.get((int) (entryId - firstId));
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public Iterator<LedgerEntry> iterator() {
          checkNotNull(entries, "entries has been recycled");
          return entries.iterator();
      }
  
      @Override
      public void close(){
          recycle();
      }
  }
  