Comunication between classes

[Gustavo Siqueira]

Hello all!
I with doubt in question between class.
See code:

Class Principal.java

//Principal.java
public class Principal {
	
	//inicia programa Java
	public static void main(String args[])
	{		
		Conta c1 = new Conta();
		Cliente myCliente = new Cliente();
		
		myCliente.setNomeCliente();
		System.out.printf("O nome do cliente: %s\n",c1.getTitular());

	}	
}

Class Conta.java

//Orientação a Objetos
//Conta.java
import java.util.Scanner; //importa a classe Scanner
public class Conta {
	
	int numero; //número da conta
	String cliente; //dono da conta
	int saldo; //saldo da conta
	double limite; //limite da conta
	
	Scanner input = new Scanner(System.in); //importa a classe Scanner	
	
	//configura o nome do cliente na conta
	public void titular(String nomeClienteItau)
	{
		this.cliente = nomeClienteItau;
	}
	
	public String getTitular()
	{
		
		return this.cliente;
		
	}
	
	//método para sacar o dinheiro
	public void Saca(int quantidade)
	{
		int novoSaldo = this.saldo - quantidade; //retira o saldo
		this.saldo = novoSaldo; //adciona a nova quantia (retirada) a novoSaldo
		
	}
	
	//método para depositar dinheiro na conta
	public void Depositar(double quantidade)
	{
		this.saldo += quantidade;
	}
	
	//retorna o novo saldo
	public int novoSaldo()
	{
		return this.saldo;
	}
}

Class Cliente.java

import java.util.Scanner; //importa a classe Scanner
public class Cliente {
	
	Scanner input = new Scanner(System.in);
	Conta adcionarConta = new Conta();
	
	String nome;
	String sobreNome;
	String cpf;
	
	//construtor que inicia mensagem de boas-vindas
	public Cliente()
	{
		System.out.println("Seja bem vindo(a) ao Banco Network!");
		System.out.println("Você está preste a ter uma conta!");
		System.out.println("Digite os seus dados corretamente!");
		
	}
	
	//método para pedir ao usuário o nome do cliente
	public void setNomeCliente()
	{
		System.out.println("Digite o seu nome: ");
		String nomeCliente = input.nextLine();
		adcionarConta.titular(nomeCliente);
	}
		
}

As can view. I pass the name client of method (setNomeCliente) with

adcionarConta.titular(nomeCliente);

for the method:

public void titular(String nomeClienteNetwork)
	{
		this.cliente = nomeClienteItau;
	}

and after, display with:

System.out.printf("O nome do cliente: %s\n",c1.getTitular());

The error that appearing how null. The that do?

[Daniel Marti]

Hello Gustavo
I would like you to pay attention to the parameter name in :

public void titular(String nomeClienteNetwork)
	{
		this.cliente = nomeClienteItau;
	}

As you can notice you call the parameter nomeClienteNetwork, but you use the content of nomeClienteItau to set the "cliente" name.
What this means is, while you pass to this method the content of nomeClienteNewtork, what you will insert in the "cliente" attribute will be the content of nomeClienteItau, which is something i cannot see declared in any point of your code.

public void titular(String nomeClienteNetwork)
	{
		this.cliente = nomeClienteNetwork;
	}

Should solve your problem.

Now for some nitpicking (hope you do not mind):

Your setNomeCliente() in the Cliente class should not have any interface with the user. A set method should only receive the parameter to set, [optional but desired] check if the parameter value is acceptable to be set to the wished attribute, and then set the attribute with the value of the parameter.
The similar problem exists in your titular method in Conta. It should be called setTitular or setCliente[preferable].

Also you do a c1.getTitular() in the System.out.printf but i can't see the declaration of that method anywhere.

[Campbell Ritchie]

Some design problems there. You have a Conta class with cliente as a field. That is dubious. A Conta (account) does not have a cliente. A Cliente has a Conta. I think you ought to remove the cliente field from the Conta class. You should have a conta field in the Cliente class, however. You also have given your methods inappropriate names. a method called setNomeCliente ought to look like this

public void setNomecliente(String nomecliente)
{
   this.nomeCliente = nomeCliente;
}

If you are "set"ting a field, then there ought to be a field with a corresponding name. Your present setNomeCliente method should have a different indentifier, maybe setNomeFromKeyboard.

Your Depositar method has two problems.

1: It should be called depositar. Not D but d.

2: You are adding a double to an int. This cannot be compiled as it stands.

I would change that method to this

public void depositar(int quantitade)
{
   if (quantitade > 0) // Do not allow negative numbers
   {
      saldo += quantitade;
   }
}

Your Saca method has similar problems. You should also consider this sort of problem: The Conta object has a saldo of 1000. You try this method call: miConta.saca(2000); You need to provide if blocks for whether the quantitade is > 0 or > saldo. I suggest, maybe, you return quantitade if it is in the right range; if it is <= 0 or > saldo, then return 0. You can use it like this.

. . .
miConta.depositar(3000);
int withdrawal = miConta.saca(5000);
System.out.println("We withdrew %d pesos%n", withdrawal);
 . . .

I hope this give you some idea how to proceed. Please ask again if you have more problems.