com.phloc.commons.id.ComparatorHasID Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of phloc-commons Show documentation
phloc very basic stuff
There is a newer version: 5.0.0
/**
 * Copyright (C) 2006-2015 phloc systems
 * http://www.phloc.com
 * office[at]phloc[dot]com
 *
 * 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 com.phloc.commons.id;

import java.util.Comparator;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import com.phloc.commons.compare.AbstractPartComparator;
import com.phloc.commons.compare.ESortOrder;

/**
 * This is a collation {@link java.util.Comparator} for objects that implement
 * the {@link IHasID} interface with a class that does NOT implements
 * {@link Comparable}.
 * 
 * @author Philip Helger
 * @param 
 *        The type of the ID
 * @param 
 *        The type of elements to be compared.
 */
public class ComparatorHasID > extends
                                                                        AbstractPartComparator 
{
  /**
   * Comparator with default sort order and no nested comparator.
   * 
   * @param aIDComparator
   *        The comparator for comparing the IDs. May not be null.
   */
  public ComparatorHasID (@Nonnull final Comparator  aIDComparator)
  {
    super (aIDComparator);
  }

  /**
   * Constructor with sort order and no nested comparator.
   * 
   * @param eSortOrder
   *        The sort order to use. May not be null.
   * @param aIDComparator
   *        The comparator for comparing the IDs. May not be null.
   */
  public ComparatorHasID (@Nonnull final ESortOrder eSortOrder, @Nonnull final Comparator  aIDComparator)
  {
    super (eSortOrder, aIDComparator);
  }

  /**
   * Comparator with default sort order and a nested comparator.
   * 
   * @param aNestedComparator
   *        The nested comparator to be invoked, when the main comparison
   *        resulted in 0.
   * @param aIDComparator
   *        The comparator for comparing the IDs. May not be null.
   */
  public ComparatorHasID (@Nullable final Comparator  aNestedComparator,
                          @Nonnull final Comparator  aIDComparator)
  {
    super (aNestedComparator, aIDComparator);
  }

  /**
   * Constructor with sort order and a nested comparator.
   * 
   * @param eSortOrder
   *        The sort order to use. May not be null.
   * @param aNestedComparator
   *        The nested comparator to be invoked, when the main comparison
   *        resulted in 0.
   * @param aIDComparator
   *        The comparator for comparing the IDs. May not be null.
   */
  public ComparatorHasID (@Nonnull final ESortOrder eSortOrder,
                          @Nullable final Comparator  aNestedComparator,
                          @Nonnull final Comparator  aIDComparator)
  {
    super (eSortOrder, aNestedComparator, aIDComparator);
  }

  @Override
  @Nullable
  protected IDTYPE getPart (final DATATYPE aObject)
  {
    return aObject.getID ();
  }
}