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.api.kv.impl.op;
  
  import com.google.common.collect.Lists;
  import io.netty.util.Recycler;
  import io.netty.util.Recycler.Handle;
  import java.util.List;
  import org.apache.bookkeeper.api.kv.op.CompareOp;
  import org.apache.bookkeeper.api.kv.op.Op;
  import org.apache.bookkeeper.api.kv.op.TxnOp;
  import org.apache.bookkeeper.api.kv.op.TxnOpBuilder;
  
  /**
   * The default implementation of {@link TxnOpBuilder}.
   * @param <K>
   * @param <V>
   */
  class TxnOpBuilderImpl<K, V> implements TxnOpBuilder<K, V> {
  
      private final Handle<TxnOpBuilderImpl<K, V>> handle;
  
      private final Recycler<TxnOpImpl<K, V>> txnOpRecycler;
      private List<CompareOp<K, V>> compareOps;
      private List<Op<K, V>> successOps;
      private List<Op<K, V>> failureOps;
  
      TxnOpBuilderImpl(Handle<TxnOpBuilderImpl<K, V>> handle,
                       Recycler<TxnOpImpl<K, V>> txnOpRecycler) {
          this.handle = handle;
          this.txnOpRecycler = txnOpRecycler;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public synchronized TxnOpBuilder<K, V> If(CompareOp... cmps) {
          if (null == compareOps) {
              compareOps = Lists.newArrayList();
          }
          for (CompareOp<K, V> cmp : cmps) {
              compareOps.add(cmp);
          }
          return this;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public synchronized TxnOpBuilder<K, V> Then(Op... ops) {
          if (null == successOps) {
              successOps = Lists.newArrayList();
          }
          for (Op<K, V> op : ops) {
              successOps.add(op);
          }
          return this;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public synchronized TxnOpBuilder<K, V> Else(Op... ops) {
          if (null == failureOps) {
              failureOps = Lists.newArrayList();
          }
          for (Op<K, V> op : ops) {
              failureOps.add(op);
          }
          return this;
      }
  
      @Override
      public synchronized TxnOp<K, V> build() {
          try {
              return txnOpRecycler.get()
                  .compareOps(compareOps)
                  .successOps(successOps)
                  .failureOps(failureOps);
          } finally {
              compareOps = null;
              successOps = null;
              failureOps = null;
              handle.recycle(this);
          }
      }
  
  }
  