/*******************************************************************************

  * Copyright (c) 2005 - 2013 Nos Doughty
  *
  * 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 org.llaith.toolkit.common.guard;

import com.google.common.base.Function;

import javax.annotation.Nullable;
import java.util.List;

/**
 * Some common static helpers for extraction until jdk8 comes along.
 */
public class Extract {

    public static <T> Function<List<T>,T> firstResult() {
        return new Function<List<T>,T>() {
            @Nullable
            @Override
            public T apply(@Nullable final List<T> input) {
                if (input == null) return null;
                return input.get(0);
            }
        };
    }

}
