List.java

package list;

import exceptions.NaoAcheiEsteTreco;
import exceptions.TaVazioBicho;

// TAD lista feito com base em lista duplamente ligada! Usando sentinelas!
// eu ia chamar de DLLList (double linked list List) mas é um nome chato!

public class List {
	private Integer size;
	private DNode start;
	private DNode end;
	
	public List() {
		size = 0;
		end = new DNode();
		start = new DNode(end);
		end.setPrevious(start);
	}
	
	public void mePrintaEssaListaMano() {
		System.out.printf("[ ");
		DNode actual = start.getNext();
		while (actual!= end) {
			if (actual == last()) System.out.printf("%s ", actual); else System.out.printf("%s, ", actual);
			actual = actual.getNext();
		}
		System.out.printf("], size: %d, isEmpty: %b%n", size(), isEmpty());
	}
	
	public Integer size() {
		return size;
	}
	
	public boolean isEmpty() {
		return (start.getNext() == end);
	}
	
	public boolean isFirst(DNode x) {
		return (start.getNext() == x);
	}
	
	public boolean isLast(DNode x) {
		return (end.getPrevious() == x);
	}
	
	public DNode first() {
		if (!isEmpty()) return start.getNext();
		else throw new TaVazioBicho("a lista tá vazia");
	}
	
	public DNode last() {
		if (!isEmpty()) return end.getPrevious();
		else throw new TaVazioBicho("a lista tá vazia");
	}
	
	public DNode before(DNode x) {
		if (x.getPrevious()!=start) return x.getPrevious(); 
		else throw new TaVazioBicho("a lista tá vazia");
	}
	
	public DNode after(DNode x) {
		if (x.getNext()!=end) return x.getNext(); 
		else throw new TaVazioBicho("a lista tá vazia");
	}
	
	public void replaceElement(DNode target, Object x) {
		target.setValue(x);
	}
	
	public void swapElements(DNode target, DNode anotherTarget) {
		Object aux = target.getValue();
		target.setValue(anotherTarget.getValue());
		anotherTarget.setValue(aux);
	}
	
	public void insertBefore(DNode target, Object x) {
		DNode novice = new DNode(target.getPrevious(), x, target);
		target.getPrevious().setNext(novice);
		target.setPrevious(novice);
		size++;
	}
	
	public void insertAfter(DNode target, Object x) {
		DNode novice = new DNode(target, x, target.getNext());
		target.getNext().setPrevious(novice);
		target.setNext(novice);
		size++;
	}
	
	public void insertFirst(Object x) {
		DNode novice = new DNode(start, x, start.getNext());
		start.getNext().setPrevious(novice);
		start.setNext(novice);
		size++;
	}
	
	public void insertLast(Object x) {
		DNode novice = new DNode(end.getPrevious(), x, end);
		end.getPrevious().setNext(novice);
		end.setPrevious(novice);
		size++;
	}
	
	public DNode remove(DNode target) {
		target.getPrevious().setNext(target.getNext());
		target.getNext().setPrevious(target.getPrevious());
		size--;
		return target;
		
	}
	
	// métodos auxiliares
	
	public DNode getNodeByValue(Object x) {
		DNode actual = start.getNext();
		
		while (actual != end) {
			// Aprendi coisas legais sobre == e .equals()!!!!!
			if (actual.getValue().equals(x)) return actual;
			actual = actual.getNext();
		}
		throw new NaoAcheiEsteTreco("Rapaz... Não achei esse ele elemento aí não...");
	}
	
}