【JAVA】四 JAVA集合 Collection ArrayList LinkedList

【JAVA】四 JAVA集合 Collection ArrayList LinkedList

Collection

Collection 已知子集

BeanContext, BeanContextServices, BlockingDeque<E>, BlockingQueue<E>, Deque<E>, 
List<E>,NavigableSet<E>, Queue<E>, Set<E>, SortedSet<E>, TransferQueue<E>

List

ArrayList

是实现了基于动态数组的数据结构 .
ArrayList的内部实现是基于基础的对象数组 . 通过源码可以看到是Object[] 数组
ArrayList实现java.util.RandomAccess 接口 .
对于随机访问get和set，ArrayList觉得优于LinkedList, 因为LinkedList要移动指针。

ArrayList私有属性

public class ArrayList<E> extends AbstractList<E>
        implements List<E>, RandomAccess, Cloneable, java.io.Serializable
{
    private static final long serialVersionUID = 8683452581122892189L;

    /** 
     *默认容量
     */
    private static final int DEFAULT_CAPACITY = 10;

    /**
     * 共享空数组实例用于空实例.
     */
    private static final Object[] EMPTY_ELEMENTDATA = {};

    /**
     * ArrayList的元素的数组缓冲区存储。
     * ArrayList的容量是这个数组的长度缓冲区。任何
     * 空ArrayList elementData = = EMPTY_ELEMENTDATA将扩大到
     * DEFAULT_CAPACITY当第一个元素被添加。
     */
    private transient Object[] elementData;

    /**
     * ArrayList的大小(它所包含的元素数量).
     *
     * @serial
     */
    private int size;
}

ArrayList构造方法

    /**
     * 构造一个与指定初始容量的空列表。
     * @param initialCapacity列表的初始容量如果指定初始容量
     * @throws IllegalArgumentException 负容量异常
     */
    public ArrayList(int initialCapacity) {
        super();
        if (initialCapacity < 0)
            throw new IllegalArgumentException("Illegal Capacity: "+
                                               initialCapacity);
        this.elementData = new Object[initialCapacity];
    }

    /**
     * 构造一个空列表的初始容量10.
     */
    public ArrayList() {
        super();
        this.elementData = EMPTY_ELEMENTDATA;
    }

    /**
     * 构造一个包含指定的元素列表收集,它们的顺序返回的集合迭代器。
     * @param c元素的集合被放置到这个列表中如果指定集合为空
     * @throws NullPointerException
     */
    public ArrayList(Collection c) {
        elementData = c.toArray();
        size = elementData.length;
        // c.toArray might (incorrectly) not return Object[] (see 6260652)
        if (elementData.getClass() != Object[].class)
            elementData = Arrays.copyOf(elementData, size, Object[].class);
    }

构造方法
ArrayList()	指定EMPTY_ELEMENTDATA,也就是一个空的ArrayList
ArrayList(int initialCapacity)	指定ArrayList 的初始化大小
ArrayList(Collection c)	接受一个Collection子集,并将这个子集转为ArrayList类型

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ArrayList添加值

    /**
     * 检查给定的指标范围。如果不是有效的范围,抛出一个运行时异常。
     * 这个方法不检查负参数,总是立即使用数组访问之前,
     * 抛出ArrayIndexOutOfBoundsException如果指数是负的。
     * 
     * PS:当用负数去访问一个数组下标时,数组就后throw new IndexOutOfBoundsException
     */
    private void rangeCheck(int index) {
        if (index >= size)
            throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
    }

    /**
     * 替换元素在这个列表中指定的位置指定的元素。
     * @param指数指数的元素来代替
     * @param元素元素存储在指定的位置 
     * @return元素之前指定的位置 
     * @throws IndexOutOfBoundsException { @inheritDoc }
     */
    public E set(int index, E element) {
        rangeCheck(index);

        E oldValue = elementData(index);
        elementData[index] = element;
        return oldValue;
    }

    /**
     * 将指定的元素添加到列表尾部。
     * @param e 元素附加到这个列表
     * @return  成功返回true  { @linkCollection  add方法})
     */
    public boolean add(E e) {
        ensureCapacityInternal(size + 1);  // Increments modCount!!
        elementData[size++] = e;
        return true;
    }


    /**
     * 通过添加和addAll rangeCheck版本使用。
     * 
     * PS:在这里验证了index是否为负数
     */
    private void rangeCheckForAdd(int index) {
        if (index > size || index < 0)
            throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
    }



    /**
     * 在指定位置插入指定的元素列表。
     * 变化的元素目前位置(如果有的话)
     * 任何后续元素向右(添加一个索引)。PS:要注意这句,这也是为什么相效于LinkedList插入对象时效率低的原因.
     * @param指数的指数是插入指定元素 
     * @param要插入元素的元素 
     * @throws IndexOutOfBoundsException { @inheritDoc }
     */
    public void add(int index, E element) {
        rangeCheckForAdd(index);

        ensureCapacityInternal(size + 1);  // Increments modCount!!
        System.arraycopy(elementData, index, elementData, index + 1,
                         size - index);
        elementData[index] = element;
        size++;
    }




    /**
     * 附加的所有元素在指定集合的末尾
     * 这个列表的顺序返回的指定集合的迭代器。
     * 这个操作的行为未定义的操作时,如果指定的集合被修改在进步。
     * (这意味着这个调用的行为定义如果这个列表指定的集合,这列表非空的。)
     * 
     * @param c collection containing elements to be added to this list
     * @return true if this list changed as a result of the call
     * @throws NullPointerException if the specified collection is null
   */
    public boolean addAll(Collection c) {
        Object[] a = c.toArray();
        int numNew = a.length;
        ensureCapacityInternal(size + numNew);  // Increments modCount
        System.arraycopy(a, 0, elementData, size, numNew);
        size += numNew;
        return numNew != 0;
    }

    /**
     * 
     * 从指定的位置将指定集合中的所有元素插入列表。
     * 变化的元素目前这个位置(如果有的话)和任何后续的元素
     * 正确的(增加他们的下标)。新元素就会出现的顺序在列表中返回的
     * 指定集合的迭代器。
     * @param index index at which to insert the first element from the
     *              specified collection
     * @param c collection containing elements to be added to this list
     * @return true if this list changed as a result of the call
     * @throws IndexOutOfBoundsException {@inheritDoc}
     * @throws NullPointerException if the specified collection is null
     */
    public boolean addAll(int index, Collection c) {
        rangeCheckForAdd(index);

        Object[] a = c.toArray();
        int numNew = a.length;
        ensureCapacityInternal(size + numNew);  // Increments modCount

        int numMoved = size - index;
        if (numMoved > 0)
            System.arraycopy(elementData, index, elementData, index + numNew,
                             numMoved);

        System.arraycopy(a, 0, elementData, index, numNew);
        size += numNew;
        return numNew != 0;
    }

关于上面的代码验证index

    private void rangeCheckForAdd(int index) {
        if (index > size || index < 0) // PS:在这里验证了index是否为负数
            throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
    }
    private void rangeCheck(int index) {
        if (index >= size) // PS:当用负数去访问一个数组下标时,数组就后throw new IndexOutOfBoundsException
            throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
    }
    这里有验证index思想没有统一,估计是两个人写的两个方法,在看看ArrayList的作者  
    @author  Josh Bloch
    @author  Neal Gafter
    这里纯属猜测 .

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ArrayList 取值

    /**
     * 返回此列表的元素在指定的位置.
     *
     * @param  index index of the element to return
     * @return the element at the specified position in this list
     * @throws IndexOutOfBoundsException {@inheritDoc}
     */
    public E get(int index) {
        rangeCheck(index);

        return elementData(index);
    }

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LinkedList

基于链表的数据结构。
LinkedList中的get方法是按照顺序从列表的一端开始检查,直到另结尾 .
LinkedList类是双向列表,列表中的每个节点都包含了对前一个和后一个元素的引用.
LinkedList实现Deque ,间接实现Queue .
对于新增和删除操作add和remove，LinedList比较占优势，因为ArrayList要移动数据。

LinkedList 私有属性

public class LinkedList<E>
    extends AbstractSequentialList<E>
    implements List<E>, Deque<E>, Cloneable, java.io.Serializable
{

    private static class Node<E> {
        E item;
        Node next;
        Node prev;

        Node(Node prev, E element, Node next) {
            this.item = element;
            this.next = next;
            this.prev = prev;
        }
    }

    transient int size = 0;

    /**
     * Pointer to first node.
     * Invariant: (first == null && last == null) ||
     *            (first.prev == null && first.item != null)
     */
    transient Node first;

    /**
     * Pointer to last node.
     * Invariant: (first == null && last == null) ||
     *            (last.next == null && last.item != null)
     */
    transient Node last;


}    

相较于ArrayList , LinkedList要有趣的多,它的first 与 last 两个节点属性是Node的静态内部类,这也证明了LinkedArrayList 是一个双向链表的数据结构 .
transient 关键字使属性在序列化时被忽略 .

LinkedList构造方法

    /**
     * Constructs an empty list.
     */
    public LinkedList() {
    }

    /**
     * 构造一个包含指定的元素列表Collection,它们的顺序返回的Collection迭代器.
     *
     * @param  c the collection whose elements are to be placed into this list
     * @throws NullPointerException if the specified collection is null
     */
    public LinkedList(Collection c) {
        this();
        addAll(c);
    }

构造方法
LinkedList()	也就是一个空的LinkedList 有 first 与 last 两个属性
LinkedList(Collection c)	接受一个Collection子集,并将这个子集转为LinkedList类型

关于Collection子集上面简单的介绍过了.

LinkedList添加值

    /**
     * Inserts the specified element at the beginning of this list.
     * 添加一个指定的对象到头
     * @param e the element to add
     */
    public void addFirst(E e) {
        linkFirst(e);
    }

    /**
     * Appends the specified element to the end of this list.
     * 添加一个指定的对象到尾
     * 
This method is equivalent to {@link #add}.
     *
     * @param e the element to add
     */
    public void addLast(E e) {
        linkLast(e);
    }


    /**
     * Links e as last element.
     */
    void linkLast(E e) {
        final Node l = last;
        final Node newNode = new Node<>(l, e, null);
        last = newNode;
        if (l == null)
            first = newNode;
        else
            l.next = newNode;
        size++;
        modCount++;
    }

    /**
     * Appends the specified element to the end of this list.
     * 添加一个指定的对象到尾
     * 
This method is equivalent to {@link #addLast}.
     *
     * @param e element to be appended to this list
     * @return {@code true} (as specified by {@link Collection#add})
     */
    public boolean add(E e) {
        linkLast(e);
        return true;
    }

    /**
     * 附加的所有元素在指定集合的末尾
     * 这个列表的顺序指定返回的集合的迭代器。
     * 这个操作的行为是未定义的指定的集合操作时被修改进步。
     * (注意,这将发生如果指定的集合这个列表,非空的)。
     *
     * @param c collection containing elements to be added to this list
     * @return {@code true} if this list changed as a result of the call
     * @throws NullPointerException if the specified collection is null
     */
    public boolean addAll(Collection c) {
        return addAll(size, c);
    }

    /**
     * 从指定的位置将指定集合中的所有元素插入列表。
     * 变化的元素目前这个位置(如果有的话)和任何后续的元素正确的(增加他们的指标)。
     * 新元素就会出现的顺序在列表中返回的指定集合的迭代器。
     *
     * @param index index at which to insert the first element
     *              from the specified collection
     * @param c collection containing elements to be added to this list
     * @return {@code true} if this list changed as a result of the call
     * @throws IndexOutOfBoundsException {@inheritDoc}
     * @throws NullPointerException if the specified collection is null
     */
    public boolean addAll(int index, Collection c) {
        checkPositionIndex(index);

        Object[] a = c.toArray();
        int numNew = a.length;
        if (numNew == 0)
            return false;

        Node pred, succ;
        if (index == size) {
            succ = null;
            pred = last;
        } else {
            succ = node(index);
            pred = succ.prev;
        }

        for (Object o : a) {
            @SuppressWarnings("unchecked") E e = (E) o;
            Node newNode = new Node<>(pred, e, null);
            if (pred == null)
                first = newNode;
            else
                pred.next = newNode;
            pred = newNode;
        }

        if (succ == null) {
            last = pred;
        } else {
            pred.next = succ;
            succ.prev = pred;
        }

        size += numNew;
        modCount++;
        return true;
    }
    /**
     * 替换的元素在这个列表的指定位置指定元素。
     *
     * @param index index of the element to replace
     * @param element element to be stored at the specified position
     * @return the element previously at the specified position
     * @throws IndexOutOfBoundsException {@inheritDoc}
     */
    public E set(int index, E element) {
        checkElementIndex(index);
        Node x = node(index);
        E oldVal = x.item;
        x.item = element;
        return oldVal;
    }

    /**
     * 在指定位置插入指定元素在这个列表中。
     * 转变当前元素(如果有的话)和任何位置
     * 后续元素向右(添加一个索引)。
     * 
     * PS : 相效于ArrayList 要移动index后所有的元素 LinkedList 要高效很多. 
     *
     * @param index index at which the specified element is to be inserted
     * @param element element to be inserted
     * @throws IndexOutOfBoundsException {@inheritDoc}
     */
    public void add(int index, E element) {
        checkPositionIndex(index);

        if (index == size)
            linkLast(element);
        else
            linkBefore(element, node(index));
    }

    /**
     * 之前插入元素e succ非空节点。.
     */
    void linkBefore(E e, Node succ) {
        // assert succ != null;
        final Node pred = succ.prev;
        final Node newNode = new Node<>(pred, e, succ);
        succ.prev = newNode;
        if (pred == null)
            first = newNode;
        else
            pred.next = newNode;
        size++;
        modCount++;
    }


    /**
     * 添加一个元素到头.
     *
     * 
This method is equivalent to {@link #addFirst}.
     *
     * @param e the element to push
     * @since 1.6
     */
    public void push(E e) {
        addFirst(e);
    }

LinkedList 取值

    /**
     * 返回头元素.
     *
     * @return the first element in this list
     * @throws NoSuchElementException if this list is empty
     */
    public E getFirst() {
        final Node f = first;
        if (f == null)
            throw new NoSuchElementException();
        return f.item;
    }

    /**
     * 返回尾元素.
     *
     * @return the last element in this list
     * @throws NoSuchElementException if this list is empty
     */
    public E getLast() {
        final Node l = last;
        if (l == null)
            throw new NoSuchElementException();
        return l.item;
    }

    /**
     * 通过下标得到元素.
     *
     * @param index index of the element to return
     * @return the element at the specified position in this list
     * @throws IndexOutOfBoundsException {@inheritDoc}
     */
    public E get(int index) {
        checkElementIndex(index);
        return node(index).item;
    }
    /**
     * node方法通过下标得到元素
     * 
     * PS : 第一次进入方法用到一个二分,之后就是for,其实可以改为二分查找 .
     */
    Node node(int index) {
        // assert isElementIndex(index);

        if (index < (size >> 1)) {
            Node x = first;
            for (int i = 0; i < index; i++)
                x = x.next;
            return x;
        } else {
            Node x = last;
            for (int i = size - 1; i > index; i--)
                x = x.prev;
            return x;
        }
    }

    /**
     * 返回头元素.
     *
     * @return the head of this list, or {@code null} if this list is empty
     * @since 1.5
     */
    public E peek() {
        final Node f = first;
        return (f == null) ? null : f.item;
    }

    /**
     * 返回头元素.
     *
     * @return the head of this list
     * @throws NoSuchElementException if this list is empty
     * @since 1.5
     */
    public E element() {
        return getFirst();
    }

    /**
     * 取得头元素, 并将头元素删除 , 将第二个元素作为头元素
     * @return the head of this list, or {@code null} if this list is empty
     * @since 1.5
     */
    public E poll() {
        final Node f = first;
        return (f == null) ? null : unlinkFirst(f);
    }
    /**
     *
     * 取得头元素 
     * 
     * PS : 此方法与 1.5 peek方法内容一至 
     * 
     * @return the first element of this list, or {@code null}
     *         if this list is empty
     * @since 1.6
     */
    public E peekFirst() {
        final Node f = first;
        return (f == null) ? null : f.item;
     }

    /**
     * 取得尾元素 .
     *
     * @return the last element of this list, or {@code null}
     *         if this list is empty
     * @since 1.6
     */
    public E peekLast() {
        final Node l = last;
        return (l == null) ? null : l.item;
    }

    /**
     * 取头,删除头,第二个元素做为头元素.
     *
     * @return the first element of this list, or {@code null} if
     *     this list is empty
     * @since 1.6
     */
    public E pollFirst() {
        final Node f = first;
        return (f == null) ? null : unlinkFirst(f);
    }

    /**
     * 取尾,删除尾,倒数第二个元素做为尾元素..
     *
     * @return the last element of this list, or {@code null} if
     *     this list is empty
     * @since 1.6
     */
    public E pollLast() {
        final Node l = last;
        return (l == null) ? null : unlinkLast(l);
    }

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ArrayList LinkedList 性能比较

package com.cn.mark.java.util;

import java.util.*;

/**
 * Created by mark on 5/22/16.
 */
public class ListTest {


    private static int N  = 50000;

    private static List values;

    private static int list_size ;

    static Random r = new Random();


    //add
    static long test_ArrayList_add_first(ArrayList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.add(0, i);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_add_first(LinkedList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.addFirst(i);
        return System.currentTimeMillis() - start;
    }

    static long test_ArrayList_add_last(ArrayList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.add(i);//ArrayList 默认加在尾
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_add_last(LinkedList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.addLast(i);
        return System.currentTimeMillis() - start;
    }

    static long test_ArrayList_add_random(ArrayList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.add(r.nextInt(N), 1);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_add_random(LinkedList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.add(r.nextInt(N), 1);
        return System.currentTimeMillis() - start;
    }


    //del
    static long test_ArrayList_del_first(ArrayList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.remove(0);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_del_first(LinkedList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.remove();// 默认删除头
        return System.currentTimeMillis() - start;
    }

    static long test_ArrayList_del_last(ArrayList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.remove(list.size()-1);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_del_last(LinkedList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.removeLast();
        return System.currentTimeMillis() - start;
    }

    static long test_ArrayList_del_random(ArrayList list){
        long start = System.currentTimeMillis();
        list_size = list.size();
        for (int i = 0; i < list_size; i++){
            list_size = list.size();
            list.remove(r.nextInt(list_size - 1));
        }
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_del_random(LinkedList list){
        long start = System.currentTimeMillis();
        list_size = list.size();
        for (int i = 0; i < list_size; i++){
            list_size = list.size();
            list.remove(r.nextInt(list_size - 1));
        }
        return System.currentTimeMillis() - start;
    }


    //modifier
    static long test_ArrayList_set_random(ArrayList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.set(r.nextInt(N), 1);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_set_random(LinkedList list){
        long start = System.currentTimeMillis();
        for (int i = 0; i <  N; i++)
            list.set(r.nextInt(N), 1);
        return System.currentTimeMillis() - start;
    }


    //query
    static long test_ArrayList_get_first(ArrayList list) {
        long start = System.currentTimeMillis();
        for (int i = 0; i < N; i++)
            list.get(i);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_get_first(LinkedList list) {
        long start = System.currentTimeMillis();
        for (int i = 0; i < N; i++)
            list.poll();
        return System.currentTimeMillis() - start;
    }

    static long test_ArrayList_get_last(ArrayList list) {
        long start = System.currentTimeMillis();
        for (int i = N-1; i >0; i--)
            list.get(i);
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_get_last(LinkedList list) {
        long start = System.currentTimeMillis();
        for (int i = 0; i < N; i++)
            list.pollLast();
        return System.currentTimeMillis() - start;
    }

    static long test_ArrayList_get_random(ArrayList list) {
        long start = System.currentTimeMillis();
        for (int i = 0; i < N; i++)
            list.get(r.nextInt(N));
        return System.currentTimeMillis() - start;
    }
    static long test_LinkedList_get_random(LinkedList list) {
        long start = System.currentTimeMillis();
        for (int i = 0; i < N; i++)
            list.get(r.nextInt(N));
        return System.currentTimeMillis() - start;
    }


    public static void main(String[] args) {

        Long vals[] = new Long[N];

        Random r = new Random();

        for (int i = 0, currval = 0; i < N; i++) {
            vals[i] = new Long(currval);
            currval += r.nextInt(100) + 1;
        }

        values = Arrays.asList(vals);


        // add
        System.out.println("test_ArrayList_add_first \t" + test_ArrayList_add_first(new ArrayList(values)));
        System.out.println("test_LinkedList_add_first \t" + test_LinkedList_add_first(new LinkedList(values)));
        System.out.println();

        System.out.println("test_ArrayList_add_last \t" + test_ArrayList_add_last(new ArrayList(values)));
        System.out.println("test_LinkedList_add_last \t" + test_LinkedList_add_last(new LinkedList(values)));
        System.out.println();

        System.out.println("test_ArrayList_add_random \t" + test_ArrayList_add_random(new ArrayList(values)));
        System.out.println("test_LinkedList_add_random \t" + test_LinkedList_add_random(new LinkedList(values)));
        System.out.println();


        //del
        System.out.println("test_ArrayList_del_first \t" + test_ArrayList_del_first(new ArrayList(values)));
        System.out.println("test_LinkedList_del_first \t" + test_LinkedList_del_first(new LinkedList(values)));
        System.out.println();

        System.out.println("test_ArrayList_del_last \t" + test_ArrayList_del_last(new ArrayList(values)));
        System.out.println("test_LinkedList_del_last \t" + test_LinkedList_del_last(new LinkedList(values)));
        System.out.println();

        System.out.println("test_ArrayList_del_random \t" + test_ArrayList_del_random(new ArrayList(values)));
        System.out.println("test_LinkedList_del_random \t" + test_LinkedList_del_random(new LinkedList(values)));
        System.out.println();

        //modifier
        System.out.println("test_ArrayList_set_random \t" + test_ArrayList_set_random(new ArrayList(values)));
        System.out.println("test_LinkedList_set_random \t" + test_LinkedList_set_random(new LinkedList(values)));
        System.out.println();


        //query
        System.out.println("test_ArrayList_get_first \t" + test_ArrayList_get_first(new ArrayList(values)));
        System.out.println("test_LinkedList_get_first \t" + test_LinkedList_get_first(new LinkedList(values)));
        System.out.println();

        System.out.println("test_ArrayList_get_last \t" + test_ArrayList_get_last(new ArrayList(values)));
        System.out.println("test_LinkedList_get_last \t" + test_LinkedList_get_last(new LinkedList(values)));
        System.out.println();
        System.out.println("test_ArrayList_get_random \t" + test_ArrayList_get_random(new ArrayList(values)));
        System.out.println("test_LinkedList_get_random \t" + test_LinkedList_get_random(new LinkedList(values)));

    }
}

运行结果

test_ArrayList_add_first    833
test_LinkedList_add_first   8

test_ArrayList_add_last     7
test_LinkedList_add_last    10

test_ArrayList_add_random   455
test_LinkedList_add_random  7905

test_ArrayList_del_first    223
test_LinkedList_del_first   5

test_ArrayList_del_last     3
test_LinkedList_del_last    4

test_ArrayList_del_random   69
test_LinkedList_del_random  713

test_ArrayList_set_random   4
test_LinkedList_set_random  1303

test_ArrayList_get_first    2
test_LinkedList_get_first   2

test_ArrayList_get_last     2
test_LinkedList_get_last    3

test_ArrayList_get_random   3
test_LinkedList_get_random  1299

Process finished with exit code 0