Thread: Strange outcome

I wrote a little exercise, it's supposed to print the months of the year in which a given fruit (passed to main as a runtime argument) can be found. It consists of two classes:

public class FruttaEVerdura {
    private String mese[];
    public FruttaEVerdura (String... mese) {
        this.setMese(mese);
    }
    public void setMese(String... mese) {
        this.mese = mese;
    }
    public String[] getMese() {
        return mese;
    }
}
 
public class TrovaStagionalita {
    public static void main(String args[]) {
        FruttaEVerdura albicocca = new FruttaEVerdura("giugno","luglio");
        FruttaEVerdura ciliegia = new FruttaEVerdura("maggio","giugno","luglio");
        FruttaEVerdura pesca = new FruttaEVerdura("giugno","luglio","agosto","settembre");
        FruttaEVerdura susina = new FruttaEVerdura("giugno","luglio","agosto","settembre");
        FruttaEVerdura uva = new FruttaEVerdura("luglio","agosto","settembre","ottobre","novembre","dicembre");
        FruttaEVerdura melone = new FruttaEVerdura("luglio","agosto","settembre");
        FruttaEVerdura cocomero = new FruttaEVerdura("giugno","luglio","agosto");
        FruttaEVerdura pera = new FruttaEVerdura("gennaio","febbraio","marzo","aprile","agosto","ottobre","novembre","dicembre");
        FruttaEVerdura mela = new FruttaEVerdura("gennaio","febbraio","marzo","aprile","settembre","ottobre","novembre","dicembre");
        FruttaEVerdura kiwi = new FruttaEVerdura("gennaio","febbraio","marzo","aprile","maggio","novembre","dicembre");
        FruttaEVerdura arancia = new FruttaEVerdura("gennaio","febbraio","marzo","aprile","maggio","novembre","dicembre");
        FruttaEVerdura fragola = new FruttaEVerdura("aprile","maggio","giugno");
        FruttaEVerdura caco = new FruttaEVerdura("ottobre","novembre");
        FruttaEVerdura castagna = new FruttaEVerdura("ottobre","novembre");
        switch (args[0]) {
            case "albicocca":
            System.out.println(albicocca.getMese());
            break;
            case "ciliegia":
            System.out.println(ciliegia.getMese());
            break;
            case "pesca":
            System.out.println(pesca.getMese());
            break;
            case "susina":
            System.out.println(susina.getMese());
            break;
            case "uva":
            System.out.println(uva.getMese());
            break;
            case "melone":
            System.out.println(melone.getMese());
            break;
            case "cocomero":
            System.out.println(cocomero.getMese());
            break;
            case "pera":
            System.out.println(pera.getMese());
            break;
            case "mela":
            System.out.println(mela.getMese());
            break;
            case "kiwi":
            System.out.println(kiwi.getMese());
            break;
            case "arancia":
            System.out.println(arancia.getMese());
            break;
            case "fragola":
            System.out.println(fragola.getMese());
            break;
            case "caco":
            System.out.println(caco.getMese());
            break;
            case "castagna":
            System.out.println(castagna.getMese());
            break;
            default:
            System.out.println("La voce inserita non e' stata trovata, riprova!");
        }
    }
}

But this instead is the outcome:
[Ljava.lang.String;@867e89
no matter which argument I pass to main method.

Each switch() branch results in a call to the fruit's method, getMese(). In the clall FruttaEVerdura, the variable mese[] is an array of strings. The method getMese() returns a the variable "mese", a reference to the array mese[] which looks like a memory address.

You might try changing the getMese() method to:

public String getMese() {
    return Arrays.toString( mese );
}

Note that the method returns a String object rather than a String[] array thanks to the Arrays.toString() method.

There are other options, but this will get you moving ahead.

Good luck!

Still isn't working...now I get an exception; for example when I run the program with the command line argument pera:

Exception in thread "main" java.lang.NoSuchMethodError: FruttaEVerdura.getMese()[Ljava/lang/String;
at TrovaStagionalita.main(TrovaStagionalita.java:40)

Shouldn't that be thrown only when the JVM can't find main?

Ahh, but it's not working differently.

Post the updated program. Providing guesses about what may or may not be wrong with code we haven't seen is pointless.

The error message should be helpful, and it's not complaining about not finding the main() method. It's complaining about not finding a method called in the main() method. You might want to stare at that a bit more and try to work out what it's telling you. Maybe you'll even determine the fix. If not, post the code.

Hello.
Just write your own custom method, say printStringArray(String s[]). In this method print each string element from the array individually.
Ex: for(String str:s) System.out.println(str);
Instead of invoking System.out.println() in the switch statement invoke printStringArray().

Syed.

Thank you, I will try that ASAP.

Originally Posted by syedbhai

Hello.
Just write your own custom method, say printStringArray(String s[]). In this method print each string element from the array individually.
Ex: for(String str:s) System.out.println(str);
Instead of invoking System.out.println() in the switch statement invoke printStringArray().

Syed.

That did it!
Thank you