Java Collection Last lastIndexOfObjectIdentity(Collection collection, Object object)

Description

Returns the index position of the last occurring object within the Collection .

License

Apache License

Parameter

Parameter	Description
collection	a parameter
object	a parameter

Return

index position of the first matching element;-1 if no element is matching

Declaration

public static <E> int lastIndexOfObjectIdentity(Collection<E> collection, Object object) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Copyright 2011 Danny Kunz/*  w w w  .ja v  a 2 s .  co  m*/
 * 
 * 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.
 ******************************************************************************/

import java.util.Collection;
import java.util.Iterator;

public class Main {
    /**
     * Returns the index position of the last occurring object within the {@link Collection}. Comparisons uses the
     * "object == element" instead of the "equals" method to determine the object identity.
     * 
     * @param collection
     * @param object
     * @return index position of the first matching element;-1 if no element is matching
     */
    public static <E> int lastIndexOfObjectIdentity(Collection<E> collection, Object object) {
        //
        int retval = -1;

        //
        if (collection != null) {
            Iterator<E> iterator = collection.iterator();
            if (iterator != null) {
                int indexPosition = 0;
                boolean lastElementWasIdenticalElement = false;
                while ((retval < 0 || lastElementWasIdenticalElement) && iterator.hasNext()) {
                    //
                    lastElementWasIdenticalElement = false;

                    //
                    E element = iterator.next();
                    if (element == object) {
                        retval = indexPosition;
                        lastElementWasIdenticalElement = true;
                    }

                    //
                    indexPosition++;
                }
            }
        }

        //
        return retval;
    }
}

Related

1. getLastElement(Collection collection, T defaultValue)
2. getLastElement(final Collection collection)
3. getLastOfCollection(Collection collection)
4. getLastOrNull(Collection collection)
5. implodeCollection(Collection items, String prefix, String suffix, String delimiter, String lastItemSuffix)