DataSet. ... public BankAccount getmaximum() { return x; }... private BankAccount maximum;... } DataSet

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Faustino Amore
6 anni fa
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1 DataSet DataSetadd DataSet BankAccount public class DataSetBankAccount { public void add(bankaccount x) { sum = sum + x.getbalance(); if (count == 0 maximum.getbalance() < x.getbalance()) maximum = x; count++; public BankAccount getmaximum() { return x; private BankAccount maximum;

2 DataSet Coin public class DataSetCoin { public void add(coin x) { sum = sum + x.getvalue(); if (count == 0 maximum.getvalue() < x.getvalue()) maximum = x; count++; public Coin getmaximum() { return x; private Coin maximum; DataSet DataSet getmeasure DataSet add sum = sum + x.getmeasure(); if (count == 0 maximum.getmeasure() < x.getmeasure()) maximum = x; count++;

3 x x getmeasure interface public interface Measurable { double getmeasure(); Measurable getmeasure double Measurable

4 public class DataSet { public void add(measurable x) { sum = sum + x.getmeasure(); if (count == 0 maximum.getmeasure() < x.getmeasure()) maximum = x; count++; public Measurable getmaximum() { return x; private Measurable maximum; DataSet Measurable Measurable public class NomeClasse implements NomeInterfaccia { /* Solita definizione di classe in cui però devono apparire, con l implementazione, tutti i metodi dichiarati nell interfaccia, con gli stessi parametri nello stesso ordine */

5 Measurable BankAccount public class BankAccount implements Measurable { public double getmeasure(){ return balance; public class Coin implements Measurable { public double getmeasure(){ return value; Measurable DataSet implements public

6 Measurable max Measurable Measurable Measurable BankAccount bankdata.add(new BankAccount(10000)); BankAccount Measurable BankAccount Measurable intdouble BankAccount: BankAccount account = new BankAccount(10000); BankAccount Measurable Measurable x = account; x Measurable x.deposit(100); // Errore!!

7 System.out.println(x.getMeasure()); x Measurable x BankAccount (x == account) account.deposit(100); // Ok Coinx Coin dime = new Coin(0.1, Dime); x = dime; // legittimo Measurable Measurable Measurable Coin dime = new Coin(0.1, Dime ); Measurable x = dime; System.out.println(x.getMeasure()); // Cast esplicito: Coin thesamedime = (Coin) x; System.out.println(theSameDime. getdescription());

8 instanceof if (x instanceof Coin) { Coin c = (Coin) x; else. public static final public interface SwingConstants { int NORTH = 1; int NORT_EAST = 2; int EAST = 3; Measurable x = ; getmeasure()x x getmeasure()

9 BankAccount getmeasure BankAccount Coin getmeasurecoin Measurable BankAccount BankAccount() BankAccount(double)

10 DataSetMeasurable Measurable Rectangle DataSet DataSet Measurable

11 public interface Measurer { double measure(object anobject); measure Object Object DataSet Measurer private Measurer measurer; public void add(object x){ sum = sum + measurer.measure(x); if (count == 0 measurer.measure(maximum) < measurer.measure(x)) maximum = x; count++; Measurer Rectangle Rectangle Measurer measure

12 class RectangleMeasurer implements Measurer { public double measure(object anobject) { Rectangle arectangle = (Rectangle) anobject; double area = arectangle.getwidth() * arectangle.getheight(); return area; RectangleMeasure Rectangle DataSet Rectangle Object RectangleMeasurer Rectangle Rectangle DataSet Measurer RectangleMeasure Rectangle PerimeterRectangleMeasurer

13 RectangleMeasurer RectangleMeasurer main DataSet public static void main (String[] args) { class RectangleMeasurer implements Measurer { Measurer m = new RectangleMeasurer(); DataSet data = new DataSet(m); DataSetStrat.java DataSetStratTest.java DataSet MeasurerEreditarietà

14 SavingsAccount BankAccount SavingsAccount class SavingsAccount extends BankAccount { BankAccount SavingsAccount deposit BankAccount SavingsAccount // Crea un conto di risparmio con // tasso di interesse fisso del 10%: SavingsAccount collegefund = new SavingsAccount(10); // utilizzo il metodo deposit ereditato // da BankAccount: collegefund.deposit(100);

15 BankAccount SavingsAccount Object BankAccount Object Object tostringequalsclone

16 SavingsAccount deposit withdraw getbalance BankAccount SavingsAccount public class SavingsAccount extends BankAccount { private double interestrate; public SavingsAccount(double rate) { public void addinterest() {

17 public class SavingsAccount extends BankAccount { public SavingsAccount(double rate) { interestrate = rate; public void addinterest() { double interest = getbalance() * interestrate / 100; deposit(interest); private double interestrate; this.getbalance() this.deposit(interest)

18 CheckingAccount BankAccount CheckingAccount deductfees deposit withdraw

20 transactioncount deductfees deposit withdraw super public class CheckingAccount extends BankAccount { public void deposit(double amount) { transactioncount++; // chiamo il metodo della superclasse super.deposit(amount); super.deposit(amount) deposit(amount) this.deposit(amount) deposit CheckingAccount OutOfMemory

21 SavingsAccount public void deposit(double amount) { transactioncount++; balance = balance + amount; // Errore balance deposit balance getbalance balance super public SavingsAccount(double amount, double rate) { super(amount); // Inizializza il saldo interestrate = rate;

22 public class CheckingAccount extends BankAccount { public CheckingAccount(double initialbalance) { // Costruisce la superclasse super(initialbalance); // Inizializza il contatore di // operazioni transactioncount = 0; SavingsAccount collegefund = new SavingsAccount(10); BankAccount anaccount = collegefund; Object anobject = collegefund;

23 collegefund SavingsAccount anaccount BankAccount anobject Object BankAccount public void transfer (double amount, BankAccount other){ this.withdraw(amount); other.deposit(amount); transfer SavingsAccountCheckingAccount SavingsAccount momssavings = new SavingsAccount(10000); CheckingAccount harrysaccount = new CheckingAccount(100); momssavings.transfer(1000, harrysaccount); other

24 public class BankAccount { public void deductfees() { //?? public abstract class BankAccount { public abstract void deductfees();

25 abstractabstract final public final class MyFinalClass { Stringfinal final final public class AccessoRemoto { public final boolean checkpassword(string password) { public private protected protected public private protected

26 protected protected protected

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