classi wrapper - altervistanew345.altervista.org/dispense/classi_wrapper.pdf · byte short int long...
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Classi Wrapper
Tipo di dato in Java che ingloba (wraps)
un valore primitivo all’interno di un oggetto.
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dati primitivi e oggetti contenitori
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Wrapper (involucro)
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Nella gerarchia di classi
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Tipi primitivi e classi wrapper
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Funzionamento
come gli oggetti String,non hanno metodi che permettono di modificarli e di conseguenza sono anche di tipo final
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Funzionamento
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Semplice esempio
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Funzionalità in doppia versione
esempio toString(..)
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Convertire da tipo numerico a tipo String: altri modi
• metodo valueOf() della classe String
• conversione implicita
Esempio di metodo (da tipo intero)
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Appendice: dati primitivi vs oggetti
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