Recovery of LinkedList

[Burma]

I'm doing a method getting in LinkedList class.

  public class Main {
        public static void main(String[] args) {
            LinkedList<Integer> list = new LinkedList<>();
            list.add(34);
            list.add(120);
            list.add(-10);
            list.add(11);
            list.add(50);
            list.add(100);
            list.add(99);
        list.addToBegin(77);
        list.addToBegin(88);
        list.addToBegin(99);

        System.out.println(list.get(3));

    }
}

public class LinkedList<T> {
private int index;

private static class Node&lt;T&gt; {
    T value;
    Node&lt;T&gt; next;

    public Node(T value) {
        this.value = value;
    }
}

private Node&lt;T&gt; first;
private Node&lt;T&gt; last;
private int size;

public void add(T element) {
    // создаю новый узел
    Node&lt;T&gt; newNode = new Node&lt;&gt;(element);
    if (size == 0) {
        first = newNode;
    } else {
        last.next = newNode;
    }
    last = newNode;
    size++;
}

public void addToBegin(T element) {
    Node&lt;T&gt; newNode = new Node&lt;&gt;(element);

    if (size == 0) {
        last = newNode;
    } else {
        newNode.next = first;
    }
    first = newNode;
    size++;
}

public int size() {
    return size;
}


public T get(int index) {
    if (index &gt; -1 &amp;&amp; index &lt; size)
        return elements[index];
    else
        System.out.println("Invalid Index");
        return null;
}

}

How do you fix my mistake?

[rosemadder]

Here's the work code:

public class Main {
    public static void main(String[] args) {
        LinkedList<Integer> list = new LinkedList<>();
        list.add(34);
        list.add(120);
        list.add(-10);
        list.add(11);
        list.add(50);
        list.add(100);
        list.add(99);
    list.addToBegin(77);
    list.addToBegin(88);
    list.addToBegin(99);

    System.out.println(list.get(5));

}

}
public class LinkedList<T> {
private int index;
private int counter;

private static class Node&lt;T&gt; {
    T value;
    Node&lt;T&gt; next;

    public Node(T value) {
        this.value = value;
    }
}

private Node&lt;T&gt; first;
private Node&lt;T&gt; last;
private int size;

public void add(T element) {
    // создаю новый узел
    Node&lt;T&gt; newNode = new Node&lt;&gt;(element);
    if (size == 0) {
        first = newNode;
    } else {
        last.next = newNode;
    }
    last = newNode;
    size++;
}

public void addToBegin(T element) {
    Node&lt;T&gt; newNode = new Node&lt;&gt;(element);

    if (size == 0) {
        last = newNode;
    } else {
        newNode.next = first;
    }
    first = newNode;
    size++;
}

public int size() {
    return size;
}


private boolean isEmpty(){
    int counter = 0;
    return false;
}

public T get(int index) {
    if (index &lt; 0 || index &gt;= size) {
        System.out.println("Invalid Index");
        return null;
    }

    Node&lt;T&gt; list = first;
    for (int i = 0; i &lt; index; i++)
        list = list.next;

    return list.value;
}

public String toString() {
    LinkedList.Node&lt;T&gt; node = this.first;
    StringBuilder sb = new StringBuilder("[");
    for (int i = 0; i &lt; size; i++) {
        sb = sb.append(node.value.toString() + " ");
        node = node.next;
    }
    sb = sb.append("]");
    return sb.toString();
}

}