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/*
 * 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.solr.common;


import java.io.IOException;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;

/**
 * Interface to help do push writing to an array
 */
public interface IteratorWriter {
  /**
   * @param iw after this method returns , the ItemWriter Object is invalid
   *          Do not hold a reference to this object
   */
  void writeIter(ItemWriter iw) throws IOException;

  interface ItemWriter {
    /**The item could be any supported type
     */
    ItemWriter add(Object o) throws IOException;

    default ItemWriter addNoEx(Object o) {
      try {
        add(o);
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
      return this;
    }

    default ItemWriter add(int v) throws IOException {
      add((Integer) v);
      return this;
    }


    default ItemWriter add(long v) throws IOException {
      add((Long) v);
      return this;
    }


    default ItemWriter add(float v) throws IOException {
      add((Float) v);
      return this;
    }

    default ItemWriter add(double v) throws IOException {
      add((Double) v);
      return this;
    }

    default ItemWriter add(boolean v) throws IOException {
      add((Boolean) v);
      return this;
    }
  }
  @SuppressWarnings({"unchecked", "rawtypes"})
  default List toList( List l)  {
    try {
      writeIter(new ItemWriter() {
        @Override
        public ItemWriter add(Object o) throws IOException {
          if (o instanceof MapWriter) o = ((MapWriter) o).toMap(new LinkedHashMap<>());
          if (o instanceof IteratorWriter) o = ((IteratorWriter) o).toList(new ArrayList<>());
          l.add(o);
          return this;
        }
      });
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
    return l;
  }
}