CSIT classes

package csit;

public class Node<T>{
    private T value;
    private Node<T> next;

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

    public Node(T value, Node<T> next){
        this.value = value;
        this.next = next;
    }

    public T getValue(){
        return value;
    }

    public Node<T> getNext(){
        return next;
    }

    public boolean hasNext(){
        return next != null;
    }

    public void setValue(T value){
        this.value = value;
    }

    public void setNext(Node<T> next){
        this.next = next;
    }

    public String toString(){
        return this.value.toString();
    }
}

public class Stack<T>{
    private Node<T> first;

    public Stack(){
        this.first = null;
    }

    public boolean isEmpty(){
        return this.first == null;
    }

    public void push(T x){
        this.first = new Node<T>(x, this.first);
    }

    public T pop(){
        T x = this.first.getValue();
        this.first = this.first.getNext();
        return x;
    }

    public T top(){
        return this.first.getValue();
    }

    public String toString(){
        String str = "[";

        Node<T> pos = this.first;
        while(pos != null){
            str = str + pos.getValue().toString();
            if(pos.getNext() != null) str = str + ", ";
            pos = pos.getNext();
        }
        str = str + "]";

        return str;
    }
}

public class Queue<T>{
    private Node<T> first;
    private Node<T> last;

    public Queue(){
        this.first = null;
        this.last = null;
    }

    public boolean isEmpty(){
        return this.first == null;
    }

    public void insert(T x){
        Node<T> temp = new Node<T>(x);
        if(this.last == null){
            this.first = temp;
        }else{
            this.last.setNext(temp);
        }
        this.last = temp;
    }

    public T remove(){
        T x = this.first.getValue();
        this.first = this.first.getNext();
        if(this.first == null) this.last = null;
        return x;
    }

    public T head(){
        return this.first.getValue();
    }

    public String toString(){
        String str = "[";
        Node<T> pos = this.first;
        while(pos != null){
            str = str + pos.getValue();
            if(pos.hasNext()) str = str + ", ";
            pos = pos.getNext();
        }
        str = str + "]";
        return str;
    }
}

public class BinNode<T>{
    private BinNode<T> left;
    private T value;
    private BinNode<T> right;

    public BinNode(T value){
        this.left = null;
        this.value = value;
        this.right = null;
    }

    public BinNode(BinNode<T> left, T value, BinNode<T> right){
        this.left = left;
        this.value = value;
        this.right = right;
    }

    public T getValue(){
        return this.value;
    }

    public void setValue(T value){
        this.value = value;
    }

    public BinNode<T> getLeft(){
        return this.left;
    }

    public BinNode<T> setLeft(BinNode<T> left){
        return this.left = left;
    }

    public boolean hasLeft(){
        return this.left != null;
    }

    public BinNode<T> getRight(){
        return this.right;
    }

    public BinNode<T> setRight(BinNode<T> right){
        return this.right = right;
    }

    public boolean hasRight(){
        return this.right != null;
    }

    public String toString(){
        return "" + this.value;
    }
}