From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Mykyta Komarn <nkomarn@hotmail.com>
Date: Wed, 30 Sep 2020 18:03:27 -0700
Subject: [PATCH] Add GlueList

This is the fastest List implementation I could find out there.

diff --git a/src/main/java/net/yatopia/server/list/GlueList.java b/src/main/java/net/yatopia/server/list/GlueList.java
new file mode 100644
index 0000000000000000000000000000000000000000..aa3064985f9d9b29660fec40c5532b02a898aa04
--- /dev/null
+++ b/src/main/java/net/yatopia/server/list/GlueList.java
@@ -0,0 +1,1051 @@
+package net.yatopia.server.list;
+
+/**
+ * Copyright 2015 Ertuğrul Çetin
+ * <p/>
+ * 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
+ * <p/>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p/>
+ * 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.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.util.AbstractList;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.ConcurrentModificationException;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.ListIterator;
+import java.util.NoSuchElementException;
+import java.util.Objects;
+
+import static java.lang.Math.abs;
+import static java.lang.Math.max;
+import static java.lang.Math.min;
+
+
+/**
+ * GlueList is a brand new List implementation which is way faster than ArrayList and LinkedList.
+ * This implementation inspired from ArrayList and LinkedList working mechanism.
+ * <br>
+ * Nodes holding data in arrays, in the beginning the world just like ArrayList ,inserts data into array one by one when there is no space for insertion to array
+ * new Node will be created and linked with the last Node.
+ * <br>
+ * The array which belongs to newly created node has half of the size of list , just like ArrayList.
+ * In ArrayList when there is no space for it it creates new array with double of old size and inserts old data into new one.
+ * Unlike ArrayList GlueList does it dynamically way with creating new node so old data does NOT have to be moved to another array.
+ * You can think that GlueList is dynamic version of ArrayList.
+ * <br>
+ * Adding and removing operations much faster than ArrayList and LinkedList.
+ * Searching operations nearly same with ArrayList and way better than LinkedList.
+ * <p/>
+ * Best Case<br>
+ * Add O(1)<br>
+ * Remove O(1)<br>
+ * Search O(1)<br>
+ * Access O(1)
+ * <br><br>
+ * "m" number of created nodes.<br>
+ * "n" size of node array.<br>
+ * If you insert 10_000_000 record into List there will be just 36 nodes.<br><br>
+ * Worst Case<br>
+ * Add O(n*m)<br>
+ * Remove O(n*m)<br>
+ * Search O(m)<br>
+ * Access O(m)
+ * <p/>
+ * version v1.0
+ * <p/>
+ * Date: 03.11.2015
+ * <p/>
+ *
+ * @author Ertuğrul Çetin ~ ertu.ctn@gmail.com
+ * @see Collection
+ * @see List
+ * @see LinkedList
+ * @see ArrayList
+ * @param <T> the type of elements held in this collection
+ */
+public class GlueList<T> extends AbstractList<T> implements List<T>, Cloneable, Serializable {
+
+    transient Node<T> first;
+    transient Node<T> last;
+
+    int size;
+
+    int initialCapacity;
+
+    private static final int DEFAULT_CAPACITY = 10;
+
+    private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
+
+    public GlueList() {
+
+        Node<T> initNode = new Node<>(null, null, 0, DEFAULT_CAPACITY);
+
+        first = initNode;
+        last = initNode;
+    }
+
+    public GlueList(int initialCapacity) {
+
+        this.initialCapacity = (initialCapacity > MAX_ARRAY_SIZE) ? MAX_ARRAY_SIZE : initialCapacity;
+
+        Node<T> initNode = new Node<>(null, null, 0, initialCapacity);
+
+        first = initNode;
+        last = initNode;
+    }
+
+    public GlueList(Collection<? extends T> c) {
+
+        Objects.requireNonNull(c);
+
+        Object[] arr = c.toArray();
+
+        int len = arr.length;
+
+        if (len != 0) {
+
+            Node<T> initNode = new Node<>(null, null, 0, len);
+
+            first = initNode;
+            last = initNode;
+
+            System.arraycopy(arr, 0, last.elementData, 0, len);
+
+            last.elementDataPointer += len;
+        } else {
+
+            Node<T> initNode = new Node<>(null, null, 0, DEFAULT_CAPACITY);
+
+            first = initNode;
+            last = initNode;
+        }
+
+        modCount++;
+        size += len;
+    }
+
+    @Override
+    public boolean add(T element) {
+
+        Node<T> l = last;
+
+        if (l.isAddable()) {
+            l.add(element);
+        } else {
+            Node<T> newNode = new Node<>(l, null, size);
+            newNode.add(element);
+            last = newNode;
+            l.next = last;
+        }
+
+        modCount++;
+        size++;
+
+        return true;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public void add(int index, T element) {
+
+        rangeCheckForAdd(index);
+
+        Node<T> node = getNodeForAdd(index);
+
+        if (node == null) {
+
+            Node<T> l = last;
+
+            Node<T> newNode = new Node<>(l, null, size);
+
+            last = newNode;
+
+            l.next = last;
+
+            node = newNode;
+        }
+
+        //if it is last and has extra space for element...
+        if (node == last && node.elementData.length - node.elementDataPointer > 0) {
+
+            int nodeArrIndex = index - node.startingIndex;
+
+            System.arraycopy(node.elementData, nodeArrIndex, node.elementData, nodeArrIndex + 1, node.elementDataPointer - nodeArrIndex);
+
+            node.elementData[nodeArrIndex] = element;
+
+            if (nodeArrIndex > 0) {
+                System.arraycopy(node.elementData, 0, node.elementData, 0, nodeArrIndex);
+            }
+
+            node.elementDataPointer++;
+        } else {
+
+            int newLen = node.elementData.length + 1;
+            T[] newElementData = (T[]) new Object[newLen];
+
+            int nodeArrIndex = index - node.startingIndex;
+
+            System.arraycopy(node.elementData, nodeArrIndex, newElementData, nodeArrIndex + 1, node.elementDataPointer - nodeArrIndex);
+
+            newElementData[nodeArrIndex] = element;
+
+            if (nodeArrIndex > 0) {
+                System.arraycopy(node.elementData, 0, newElementData, 0, nodeArrIndex);
+            }
+
+            node.elementData = newElementData;
+            node.endingIndex++;
+            node.elementDataPointer++;
+        }
+
+        updateNodesAfterAdd(node);
+
+        modCount++;
+        size++;
+    }
+
+    private void rangeCheckForAdd(int index) {
+
+        if (index > size || index < 0) {
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
+    }
+
+    private void updateNodesAfterAdd(Node<T> nodeFrom) {
+
+        for (Node<T> node = nodeFrom.next; node != null; node = node.next) {
+
+            node.startingIndex++;
+            node.endingIndex++;
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public boolean addAll(Collection<? extends T> c) {
+
+        Objects.requireNonNull(c);
+
+        Object[] collection = c.toArray();
+
+        int len = collection.length;
+
+        if (len == 0) {
+            return false;
+        }
+
+        if (size == 0) {
+
+            if (initialCapacity >= len) {
+                System.arraycopy(collection, 0, last.elementData, 0, len);
+            } else {
+                last.elementData = Arrays.copyOf((T[]) collection, len);
+                last.endingIndex = len - 1;
+            }
+
+            last.elementDataPointer += len;
+
+            modCount++;
+            size += len;
+
+            return true;
+        }
+
+        int elementDataLen = last.elementData.length;
+        int elementSize = last.elementDataPointer;
+
+        int remainedStorage = elementDataLen - elementSize;
+
+        if (remainedStorage == 0) {
+
+            Node<T> l = last;
+
+            int newLen = (size >>> 1);
+            int initialLen = (len > newLen) ? len : newLen;
+
+            Node<T> newNode = new Node<>(l, null, size, initialLen);
+
+            System.arraycopy(collection, 0, newNode.elementData, 0, len);
+
+            newNode.elementDataPointer += len;
+
+            last = newNode;
+            l.next = last;
+
+            modCount++;
+            size += len;
+
+            return true;
+        }
+
+        if (len <= remainedStorage) {
+
+            System.arraycopy(collection, 0, last.elementData, elementSize, len);
+
+            last.elementDataPointer += len;
+
+            modCount++;
+            size += len;
+
+            return true;
+        }
+
+        if (len > remainedStorage) {
+
+            System.arraycopy(collection, 0, last.elementData, elementSize, remainedStorage);
+
+            last.elementDataPointer += remainedStorage;
+            size += remainedStorage;
+
+            int newLen = (size >>> 1);
+            int remainedDataLen = len - remainedStorage;
+
+            int initialLen = (newLen > remainedDataLen) ? newLen : remainedDataLen;
+
+            Node<T> l = last;
+
+            Node<T> newNode = new Node<>(l, null, size, initialLen);
+
+            System.arraycopy(collection, remainedStorage, newNode.elementData, 0, remainedDataLen);
+
+            newNode.elementDataPointer += remainedDataLen;
+
+            last = newNode;
+            l.next = last;
+
+            modCount++;
+            size += remainedDataLen;
+
+            return true;
+        }
+
+        return false;
+    }
+
+    @Override
+    public T set(int index, T element) {
+
+        rangeCheck(index);
+
+        Node<T> node = getNode(index);
+
+        int nodeArrIndex = index - node.startingIndex;
+
+        T oldValue = node.elementData[nodeArrIndex];
+
+        node.elementData[nodeArrIndex] = element;
+
+        return oldValue;
+    }
+
+    @Override
+    public T get(int index) {
+
+        rangeCheck(index);
+
+        Node<T> node = getNode(index);
+
+        return node.elementData[index - node.startingIndex];
+    }
+
+    @Override
+    public int indexOf(Object o) {
+
+        int index = 0;
+
+        if (o == null) {
+
+            for (Node<T> node = first; node != null; node = node.next) {
+                for (int i = 0; i < node.elementDataPointer; i++) {
+                    if (node.elementData[i] == null) {
+                        return index;
+                    }
+                    index++;
+                }
+            }
+        } else {
+
+            for (Node<T> node = first; node != null; node = node.next) {
+                for (int i = 0; i < node.elementDataPointer; i++) {
+                    if (o.equals(node.elementData[i])) {
+                        return index;
+                    }
+                    index++;
+                }
+            }
+        }
+
+        return -1;
+    }
+
+    @Override
+    public int lastIndexOf(Object o) {
+
+        int index = size - 1;
+
+        if (o == null) {
+            for (Node<T> node = last; node != null; node = node.pre) {
+                for (int i = node.elementDataPointer - 1; i >= 0; i--) {
+                    if (node.elementData[i] == null) {
+                        return index;
+                    }
+                    index--;
+                }
+            }
+        } else {
+
+            for (Node<T> node = last; node != null; node = node.pre) {
+                for (int i = node.elementDataPointer - 1; i >= 0; i--) {
+                    if (o.equals(node.elementData[i])) {
+                        return index;
+                    }
+                    index--;
+                }
+            }
+        }
+
+        return -1;
+    }
+
+    @Override
+    public boolean contains(Object o) {
+        return indexOf(o) != -1;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public T remove(int index) {
+
+        rangeCheck(index);
+
+        Node<T> node;
+
+        if (size == 2 && first != last) {
+
+            Node<T> newNode = new Node<>(null, null, 0, 2);
+            newNode.add(first.elementData[0]);
+            newNode.add(last.elementData[0]);
+
+            node = first = last = newNode;
+        } else {
+            node = getNode(index);
+        }
+
+        T[] elementData = node.elementData;
+
+        int elementSize = node.elementDataPointer;
+
+        int nodeArrIndex = index - node.startingIndex;
+
+        T oldValue = elementData[nodeArrIndex];
+
+        int numMoved = elementSize - nodeArrIndex - 1;
+
+        if (numMoved > 0) {
+            System.arraycopy(node.elementData, nodeArrIndex + 1, node.elementData, nodeArrIndex, numMoved);
+        }
+
+        if (first == last || node == last) {
+            node.elementData[elementSize - 1] = null;
+        } else {
+            node.elementData = Arrays.copyOf(node.elementData, elementSize - 1);
+            node.endingIndex = (--node.endingIndex < 0) ? 0 : node.endingIndex;
+        }
+
+        node.elementDataPointer--;
+
+        updateNodesAfterRemove(node);
+
+        if (node.elementDataPointer == 0 && first != last) {
+
+            Node<T> next = node.next;
+            Node<T> prev = node.pre;
+
+            if (prev == null) {
+                first = next;
+            } else {
+                prev.next = next;
+                node.pre = null;
+            }
+
+            if (next == null) {
+                last = prev;
+            } else {
+                next.pre = prev;
+                node.next = null;
+            }
+
+            node.elementData = null;
+        }
+
+        size--;
+        modCount++;
+
+        return oldValue;
+    }
+
+    @Override
+    public boolean removeAll(Collection<?> c) {
+
+        Objects.requireNonNull(c);
+
+        Object[] arr = c.toArray();
+        if (arr.length == 0) {
+            return false;
+        }
+
+        boolean isModified = false;
+
+        for (Object o : arr) {
+            isModified |= remove(o);
+        }
+
+        return isModified;
+    }
+
+    @Override
+    public boolean retainAll(Collection<?> c) {
+
+        Objects.requireNonNull(c);
+
+        Object[] arr = c.toArray();
+        if (arr.length == 0) {
+            return false;
+        }
+
+        boolean isModified = false;
+
+        Object[] elements = toArray();
+
+        for (Object element : elements) {
+
+            if (!c.contains(element)) {
+                isModified |= remove(element);
+            }
+        }
+
+        return isModified;
+    }
+
+    @Override
+    public boolean remove(Object o) {
+
+        int index = indexOf(o);
+
+        if (index != -1) {
+            remove(index);
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    private void updateNodesAfterRemove(Node<T> fromNode) {
+
+        for (Node<T> node = fromNode.next; node != null; node = node.next) {
+
+            node.startingIndex = (--node.startingIndex < 0) ? 0 : node.startingIndex;
+            node.endingIndex = (--node.endingIndex < 0) ? 0 : node.endingIndex;
+        }
+    }
+
+    private Node<T> getNode(int index) {
+
+        int firstStartingIndex = first.startingIndex;
+        int firstEndingIndex = first.endingIndex;
+
+        int firstMinDistance = min(abs(index - firstStartingIndex), abs(index - firstEndingIndex));
+
+        int lastStartingIndex = last.startingIndex;
+        int lastEndingIndex = last.endingIndex;
+
+        int lastMinDistance = min(abs(index - lastStartingIndex), abs(index - lastEndingIndex));
+
+        if (firstMinDistance <= lastMinDistance) {
+
+            Node<T> node = first;
+            do {
+
+                if (node.startingIndex <= index && index <= node.endingIndex) {
+                    return node;
+                }
+
+                node = node.next;
+            } while (true);
+        } else {
+
+            Node<T> node = last;
+            do {
+
+                if (node.startingIndex <= index && index <= node.endingIndex) {
+                    return node;
+                }
+
+                node = node.pre;
+            } while (true);
+        }
+    }
+
+    private Node<T> getNodeForAdd(int index) {
+
+        if (index == size && !(last.startingIndex <= index && index <= last.endingIndex)) {
+            return null;
+        }
+
+        return getNode(index);
+    }
+
+    private void rangeCheck(int index) {
+
+        if (index >= size || index < 0) {
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
+    }
+
+    @Override
+    public void clear() {
+
+        for (Node<T> node = first; node != null; ) {
+
+            Node<T> next = node.next;
+
+            node.next = null;
+            node.pre = null;
+            node.elementData = null;
+
+            node = next;
+        }
+
+        first = last = null;
+
+        int capacity = min(MAX_ARRAY_SIZE, max(size, max(initialCapacity, DEFAULT_CAPACITY)));
+
+        Node<T> initNode = new Node<>(null, null, 0, capacity);
+
+        initialCapacity = capacity;
+
+        first = initNode;
+        last = initNode;
+
+        modCount++;
+        size = 0;
+    }
+
+    public void trimToSize() {
+
+        int pointer = last.elementDataPointer;
+        int arrLen = last.elementData.length;
+
+        if (pointer < arrLen && arrLen > 2) {
+
+            if (pointer < 2) {
+                last.elementData = Arrays.copyOf(last.elementData, 2);
+                last.endingIndex -= arrLen - 2;
+            } else {
+                last.elementData = Arrays.copyOf(last.elementData, pointer);
+                last.endingIndex -= arrLen - pointer;
+            }
+        }
+    }
+
+    @Override
+    public List<T> subList(int fromIndex, int toIndex) {
+        return super.subList(fromIndex, toIndex);
+    }
+
+    @Override
+    public Object[] toArray() {
+
+        Object[] objects = new Object[size];
+
+        int i = 0;
+        for (Node<T> node = first; node != null; node = node.next) {
+
+            int len = node.elementDataPointer;
+
+            if (len > 0) {
+                System.arraycopy(node.elementData, 0, objects, i, len);
+            }
+
+            i += len;
+        }
+
+        return objects;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T[] toArray(T[] a) {
+        return (T[]) Arrays.copyOf(toArray(), size, a.getClass());
+    }
+
+    public boolean isEmpty() {
+        return size == 0;
+    }
+
+    @Override
+    public Iterator<T> iterator() {
+        return new Itr();
+    }
+
+    private class Itr implements Iterator<T> {
+
+        Node<T> node = first;
+
+        int i = 0;//inner-array index
+        int j = 0;//total index -> cursor
+
+        int lastReturn = -1;
+
+        int expectedModCount = modCount;
+        int elementDataPointer = node.elementDataPointer;
+
+        @Override
+        public boolean hasNext() {
+            return j != size;
+        }
+
+        @Override
+        public T next() {
+
+            checkForComodification();
+
+            if (j >= size) {
+                throw new NoSuchElementException();
+            }
+
+            if (j >= last.endingIndex + 1) {
+                throw new ConcurrentModificationException();
+            }
+
+            if (j == 0) {// it's for listIterator.when node becomes null.
+                node = first;
+                elementDataPointer = node.elementDataPointer;
+                i = 0;
+            }
+
+            T val = node.elementData[i++];
+
+            if (i >= elementDataPointer) {
+                node = node.next;
+                i = 0;
+                elementDataPointer = (node != null) ? node.elementDataPointer : 0;
+            }
+
+            lastReturn = j++;
+
+            return val;
+        }
+
+        @Override
+        public void remove() {
+
+            if (lastReturn < 0) {
+                throw new IllegalStateException();
+            }
+
+            checkForComodification();
+
+            try {
+                GlueList.this.remove(lastReturn);
+
+                j = lastReturn;
+
+                lastReturn = -1;
+
+                i = (--i < 0) ? 0 : i;
+
+                elementDataPointer = (node != null) ? node.elementDataPointer : 0;
+
+                expectedModCount = modCount;
+            } catch (IndexOutOfBoundsException e) {
+                throw new ConcurrentModificationException();
+            }
+        }
+
+        void checkForComodification() {
+            if (modCount != expectedModCount) {
+                throw new ConcurrentModificationException();
+            }
+        }
+    }
+
+    @Override
+    public ListIterator<T> listIterator(int index) {
+
+        checkPositionIndex(index);
+
+        return new ListItr(index);
+    }
+
+    private void checkPositionIndex(int index) {
+
+        if (!(index >= 0 && index <= size)) {
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
+    }
+
+    @Override
+    public ListIterator<T> listIterator() {
+        return new ListItr(0);
+    }
+
+    private class ListItr extends Itr implements ListIterator<T> {
+
+        public ListItr(int index) {
+            node = (index == size) ? last : getNode(index);
+            j = index;
+            i = index - node.startingIndex;
+            elementDataPointer = node.elementDataPointer;
+        }
+
+        @Override
+        public boolean hasPrevious() {
+            return j != 0;
+        }
+
+        @Override
+        public T previous() {
+
+            checkForComodification();
+
+            int temp = j - 1;
+
+            if (temp < 0) {
+                throw new NoSuchElementException();
+            }
+
+            if (temp >= last.endingIndex + 1) {
+                throw new ConcurrentModificationException();
+            }
+
+            if (j == size) {
+
+                node = last;
+
+                elementDataPointer = node.elementDataPointer;
+
+                i = elementDataPointer;
+            }
+
+            int index = j - node.startingIndex;
+            if (index == 0) {
+
+                node = node.pre;
+
+                elementDataPointer = node.elementDataPointer;
+
+                i = elementDataPointer;
+            }
+
+            T val = node.elementData[--i];
+
+            if (i < 0) {
+                node = node.pre;
+                i = (node != null) ? node.elementDataPointer : 0;
+            }
+
+            j = temp;
+
+            lastReturn = j;
+
+            return val;
+        }
+
+        @Override
+        public int nextIndex() {
+            return j;
+        }
+
+        @Override
+        public int previousIndex() {
+            return j - 1;
+        }
+
+        @Override
+        public void set(T t) {
+
+            if (lastReturn < 0) {
+                throw new IllegalStateException();
+            }
+
+            checkForComodification();
+
+            try {
+                GlueList.this.set(lastReturn, t);
+            } catch (IndexOutOfBoundsException e) {
+                throw new ConcurrentModificationException();
+            }
+        }
+
+        @Override
+        public void add(T t) {
+
+            checkForComodification();
+
+            try {
+                int temp = j;
+
+                GlueList.this.add(temp, t);
+
+                j = temp + 1;
+
+                lastReturn = -1;
+
+                i++;
+                elementDataPointer = (node != null) ? node.elementDataPointer : 0;
+
+                expectedModCount = modCount;
+            } catch (IndexOutOfBoundsException e) {
+                throw new ConcurrentModificationException();
+            }
+        }
+    }
+
+    @Override
+    public int size() {
+        return size;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public Object clone() {
+
+        try {
+            GlueList<T> clone = (GlueList<T>) super.clone();
+
+            clone.first = clone.last = null;
+
+            int capacity = min(MAX_ARRAY_SIZE, max(clone.size, max(clone.initialCapacity, DEFAULT_CAPACITY)));
+
+            Node<T> initNode = new Node<>(null, null, 0, capacity);
+
+            clone.initialCapacity = capacity;
+
+            clone.first = clone.last = initNode;
+
+            clone.modCount = 0;
+            clone.size = 0;
+
+            for (Node<T> node = first; node != null; node = node.next) {
+
+                for (int i = 0; i < node.elementDataPointer; i++) {
+                    clone.add(node.elementData[i]);
+                }
+            }
+
+            return clone;
+        } catch (CloneNotSupportedException e) {
+            throw new InternalError();
+        }
+    }
+
+    private void writeObject(ObjectOutputStream s) throws IOException {
+
+        int expectedModCount = modCount;
+
+        s.defaultWriteObject();
+
+        s.writeInt(size);
+
+        for (Node<T> node = first; node != null; node = node.next) {
+            for (int i = 0; i < node.elementDataPointer; i++) {
+                s.writeObject(node.elementData[i]);
+            }
+        }
+
+        if (modCount != expectedModCount) {
+            throw new ConcurrentModificationException();
+        }
+    }
+
+
+    @SuppressWarnings("unchecked")
+    private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
+
+        clear();
+
+        s.defaultReadObject();
+
+        int size = s.readInt();
+
+        for (int i = 0; i < size; i++) {
+            last.add((T) s.readObject());
+        }
+    }
+
+    static class Node<T> {
+
+        Node<T> pre;
+        Node<T> next;
+
+        int listSize;
+
+        int startingIndex;
+        int endingIndex;
+
+        T[] elementData;
+        int elementDataPointer;
+
+        @SuppressWarnings("unchecked")
+        Node(Node<T> pre, Node<T> next, int listSize) {
+            this.pre = pre;
+            this.next = next;
+            this.listSize = listSize;
+            this.elementData = (T[]) new Object[listSize >>> 1];
+            this.startingIndex = listSize;
+            this.endingIndex = listSize + elementData.length - 1;
+        }
+
+        Node(Node<T> pre, Node<T> next, int listSize, int initialCapacity) {
+            this.pre = pre;
+            this.next = next;
+            this.listSize = listSize;
+            this.elementData = createElementData(initialCapacity);
+            this.startingIndex = listSize;
+            this.endingIndex = listSize + elementData.length - 1;
+        }
+
+        @SuppressWarnings("unchecked")
+        T[] createElementData(int capacity) {
+
+            if (capacity == 0 || capacity == 1) {
+                return (T[]) new Object[DEFAULT_CAPACITY];
+            } else if (capacity > 1) {
+                return (T[]) new Object[capacity];
+            } else {
+                throw new IllegalArgumentException("Illegal Capacity: " + capacity);
+            }
+        }
+
+        boolean isAddable() {
+            return elementDataPointer < elementData.length;
+        }
+
+        void add(T element) {
+            elementData[elementDataPointer++] = element;
+        }
+
+        @Override
+        public String toString() {
+            return String.format("[sIndex: %d - eIndex: %d | elementDataPointer: %d | elementDataLength: %d]", startingIndex, endingIndex, elementDataPointer, elementData.length);
+        }
+    }
+}
\ No newline at end of file