I don't know how to use try/catch

[André Asantos]

please, i would like to know how to configure way to return a message to the user when types a wrong number as 1.5 or when don't exist the number
typed...

//método pega cliente   
    public static Cliente getCliente(Cliente c1) {   
        try{   
        Cliente c = new Cliente();   
        for (Cliente c2 : listaTodosClientes()) {// percorrer lista   
            if (c1.getId() == c2.getId()) {// verifica se existe na lista   
                c = c2;   
            }   
       
        }   
       
        }   
       
        catch(NullPointerException e) {   
            System.out.println("Você não digitou um número ID que não há na lista, isto é, não tem este cliente cadastrado até então !!!");   
        }   
        return c1;   
       
           
    }  

metodo main

//getCliente   
    Cliente cnovo = new Cliente();   
    cnovo.setId(444);   
    System.out.println("O CLIENTE ENCONTRADO FOI: " + getCliente(cnovo).getNome());  

[Seetharaman Venkatasamy]

here, there is no reason to use try/catch . what is the use of catching a NullPointerException ?

[André Asantos]

Hmmm

but how could I treat that situation please?


bye,
André AS

[Rob Spoor]

Use == null and/or != null to make sure none of the variables is null.

[Jesper de Jong]

Some remarks: What exactly is the purpose of your getCliente() method - what should it do and what should it return? Note that as it is written above, the method effectively does nothing at all - it always returns the same Cliente object that you passed into it.

In line 4, why are you creating a new Cliente object? You're not using that object anywhere, and in line 7 you're assigning a different value to variable c, throwing away the Cliente object that you created earlier.