code: /*
   * Copyright 2012-2018 Chronicle Map Contributors
   *
   * Licensed 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 net.openhft.chronicle.map.impl.stage.data.bytes;
  
  import net.openhft.chronicle.bytes.BytesStore;
  import net.openhft.chronicle.bytes.RandomDataInput;
  import net.openhft.chronicle.bytes.VanillaBytes;
  import net.openhft.chronicle.hash.AbstractData;
  import net.openhft.chronicle.hash.impl.stage.hash.CheckOnEachPublicOperation;
  import net.openhft.chronicle.map.impl.stage.map.ValueBytesInterop;
  import net.openhft.sg.Stage;
  import net.openhft.sg.StageRef;
  import net.openhft.sg.Staged;
  
  import static net.openhft.chronicle.bytes.NoBytesStore.NO_BYTES_STORE;
  
  @Staged
  public class WrappedValueBytesData<V> extends AbstractData<V> {
  
      @Stage("WrappedValueBytes")
      private final VanillaBytes wrappedValueBytes = VanillaBytes.vanillaBytes();
      @StageRef
      ValueBytesInterop<V> vi;
      @StageRef
      CheckOnEachPublicOperation checkOnEachPublicOperation;
      private WrappedValueBytesData<V> next;
      @Stage("WrappedValueBytesStore")
      private BytesStore wrappedValueBytesStore;
      @Stage("WrappedValueBytesStore")
      private long wrappedValueBytesOffset;
      @Stage("WrappedValueBytesStore")
      private long wrappedValueBytesSize;
      @Stage("WrappedValueBytes")
      private boolean wrappedValueBytesUsed = false;
      @Stage("CachedWrappedValue")
      private V cachedWrappedValue;
      @Stage("CachedWrappedValue")
      private boolean cachedWrappedValueRead = false;
  
      boolean nextInit() {
          return true;
      }
  
      void closeNext() {
          // do nothing
      }
  
      @Stage("Next")
      public WrappedValueBytesData<V> getUnusedWrappedValueBytesData() {
          if (!wrappedValueBytesStoreInit())
              return this;
          if (next == null)
              next = new WrappedValueBytesData<>();
          return next.getUnusedWrappedValueBytesData();
      }
  
      boolean wrappedValueBytesStoreInit() {
          return wrappedValueBytesStore != null;
      }
  
      public void initWrappedValueBytesStore(BytesStore bytesStore, long offset, long size) {
          wrappedValueBytesStore = bytesStore;
          wrappedValueBytesOffset = offset;
          wrappedValueBytesSize = size;
      }
  
      void closeWrappedValueBytesStore() {
          wrappedValueBytesStore = null;
          if (next != null)
              next.closeWrappedValueBytesStore();
      }
  
      boolean wrappedValueBytesInit() {
          return wrappedValueBytesUsed;
      }
  
      void initWrappedValueBytes() {
          wrappedValueBytes.bytesStore(
                  wrappedValueBytesStore, wrappedValueBytesOffset, wrappedValueBytesSize);
          wrappedValueBytesUsed = true;
      }
  
      void closeWrappedValueBytes() {
          wrappedValueBytes.bytesStore(NO_BYTES_STORE, 0, 0);
          wrappedValueBytesUsed = false;
      }
  
      private void initCachedWrappedValue() {
          cachedWrappedValue = innerGetUsing(cachedWrappedValue);
          cachedWrappedValueRead = true;
      }
  
      @Override
      public RandomDataInput bytes() {
          checkOnEachPublicOperation.checkOnEachPublicOperation();
          return wrappedValueBytes.bytesStore();
      }
  
      @Override
      public long offset() {
          checkOnEachPublicOperation.checkOnEachPublicOperation();
          return wrappedValueBytesOffset;
      }
  
      @Override
      public long size() {
          checkOnEachPublicOperation.checkOnEachPublicOperation();
          return wrappedValueBytesSize;
      }
  
      @Override
      public V get() {
          checkOnEachPublicOperation.checkOnEachPublicOperation();
          return cachedWrappedValue;
      }
  
      @Override
      public V getUsing(V using) {
          checkOnEachPublicOperation.checkOnEachPublicOperation();
          return innerGetUsing(using);
      }
  
      private V innerGetUsing(V usingValue) {
          wrappedValueBytes.readPosition(wrappedValueBytesOffset);
          return vi.valueReader.read(wrappedValueBytes, wrappedValueBytesSize, usingValue);
      }
  }
  