lista java - lista

public class Lista {
    protected Node head;
    protected Node tail;
    protected long size;

    public Lista(){
        head = null;
        tail = null;
        size = 0;
    }

    public void insereInicio(Node n){
        n.setProximo(head);
        head = n;
        size += 1;
        if(size==1){
            tail = n;
        }
    }

    public void insereFim(Node n){
        tail.setProximo(n);
        tail = n;
        size = size + 1;

        if(size==1){
            head = n;
        }
    }

    public boolean removeInicio() {
        if(size!=0) {
            head = head.getProximo();
            size -=1;
            return true;
        }
        else {
            System.out.println("Lista vazia.");
            return false;
        }
    }

    public boolean removeFim() {
        if(size!=0) {
            Node n = head;
            int i;
            for(i=1;i<size-1;i++) {
                n = n.getProximo();
            }
            System.out.println(i+" iterações.\n");
            tail = n;
            tail.setProximo(null);
            size -=1;
            return true;
        }
        else {
            System.out.println("Lista vazia.");
            return false;
        }
    }

    public boolean busca(int valor) {
        if(size==0) return false;
        Node n = head;
        for(int i=1;i<=size;i++) {
            if(valor==n.getValor()) {
                return true;
            }
            else {
                n = n.getProximo();
            }
        }
        return false;
    }

    public Node getHead() {
        return head;
    }

    public void setHead(Node head) {
        this.head = head;
    }

    public Node getTail() {
        return tail;
    }

    public void setTail(Node tail) {
        this.tail = tail;
    }

    public long getSize() {
        return size;
    }

    public void setSize(long size) {
        this.size = size;
    }

    public String toString(){
        Node cursor;
        cursor = head;
        while(cursor != null){
            System.out.println(cursor.getValor());
            cursor = cursor.getProximo();
        }
        return null;
    }
}