ContaBuilder Alternativo

Builder.java

package br.com.caelum.fj91.banco.modelo;

import java.math.BigDecimal;

public interface Builder{
	Builder comLimite(BigDecimal limite);
	Builder comTitular(Cliente titular);
	Conta cria();
}

ContaBuilder2.java

package br.com.caelum.fj91.banco.modelo;

import java.math.BigDecimal;
import java.util.Calendar;

public class ContaBuilder2 implements Numero, Data, Builder{

	private Conta c;
	private int numero;
	private Calendar dataAbertura;

	private ContaBuilder2(){}
	
	@Override
	public Builder comLimite(BigDecimal limite) {
		c.setLimite(limite);
		return this;
	}

	@Override
	public Builder comTitular(Cliente titular) {
		c.setTitular(titular);
		return this;
	}
	
	@Override
	public Data comNumero(int numero){
		this.numero = numero;
		return this;
	}
	
	@Override
	public Builder comData(Calendar dataAbertura){
		this.dataAbertura = dataAbertura;
		this.c = new Conta(numero,this.dataAbertura);
		return this;
	}

	@Override
	public Conta cria() {
		return c;
	}
	
	public static Numero novaConta() {
		return new ContaBuilder2();
	}	
	
}

Data.java

package br.com.caelum.fj91.banco.modelo;

import java.util.Calendar;

public interface Data{
	Builder comData(Calendar data);
}

Numero.java

package br.com.caelum.fj91.banco.modelo;

public interface Numero{
	Data comNumero(int numero);
}