crunch-core/src/main/java/org/apache/crunch/types/UnionDeepCopier.java

/**
 * 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.crunch.types;

import com.google.common.collect.Lists;
import org.apache.crunch.Union;
import org.apache.hadoop.conf.Configuration;

import java.util.List;

public class UnionDeepCopier implements DeepCopier<Union> {
  private final List<PType> elementTypes;

  public UnionDeepCopier(PType... elementTypes) {
    this.elementTypes = Lists.newArrayList(elementTypes);
  }

  @Override
  public void initialize(Configuration conf) {
    for (PType elementType : elementTypes) {
      elementType.initialize(conf);
    }
  }

  @Override
  public Union deepCopy(Union source) {
    if (source == null) {
      return null;
    }
    int index = source.getIndex();
    Object copy = elementTypes.get(index).getDetachedValue(source.getValue());
    return new Union(index, copy);
  }
}