constructor-super, new methods2-3

Week 5: Class hierarchies/10B. Better wallet

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+The program defines a class 'Wallet', which, in addition to the 
+constructor and 
+the balance detection method, 
+has the method addMoney(double money), which can be used to add money to the wallet.
+
+
+Write the class 'BetterWallet', which inherits the class 'Wallet'. 
+In addition to the constructor, the new class has 2 overloaded new versions of the method addMoney:
+addMoney(int euros, int cents), which gets the euros and cents added separately
+addMoney(String amount), which receives the amount of money as a string.
+
+
+An example to illustrate how the class works:
+public static void main(String[] args) {
+    BetterWallet wallet = new BetterWallet(10);
+    
+    System.out.println(wallet.getMoney());
+    
+    wallet.addMoney(5.0);
+    System.out.println(wallet.getMoney());
+    
+    wallet.addMoney(2, 75);
+    System.out.println(wallet.getMoney());
+    
+    wallet.addMoney("3.50");
+    System.out.println(wallet.getMoney());
+}
+
+Program outputs:
+10.0
+15.0
+17.75
+21.25
+
+
+
+
+
+
+
+import java.util.Random;
+
+public class Test{
+    public static void main(String[] args){
+        final Random r = new Random();
+        
+        
+          
+        
+        double[] desit = {0.25, 0.5, 0.75, 0.99, 0.65, 0.30};
+        System.out.println("Testing class BetterWallet...");
+        
+        BetterWallet bw = new BetterWallet(r.nextInt(100) + 1);
+        
+        // testing for inheritance
+        Wallet wallet = (Wallet) bw;
+        
+        System.out.println("Object created!");
+        
+        System.out.println("Money now: " + bw.getMoney());
+        
+        double money = r.nextInt(100) + 1 + desit[r.nextInt(desit.length)];
+        System.out.println("Adding " + money);
+        bw.addMoney(money);
+        
+        System.out.println("Money now: " + bw.getMoney());
+        
+        int euros = r.nextInt(100) + 1;
+        int cents = r.nextInt(99) + 1;
+        System.out.println("Adding " + euros + " euros and " + cents + " cents");
+        bw.addMoney(euros, cents);
+        
+        System.out.println("Money now: " + bw.getMoney());
+        
+        euros = r.nextInt(100) + 1;
+        cents = r.nextInt(99) + 1;
+        
+        String increment = euros + "." + cents;
+        
+        System.out.println("Adding \"" + increment + "\"");
+        bw.addMoney(increment);
+        
+        System.out.println("Money now: " + bw.getMoney());
+    }
+}
+
+class Wallet {
+    protected double money;
+
+    public Wallet(double money) {
+        this.money = money;
+    }
+    
+    public void addMoney(double amount) {
+        money += amount;
+    }
+    
+    public double getMoney() {
+        return money;
+    }
+}
+
+
+
+
+
+
+//ADD
+class BetterWallet extends Wallet {
+
+    //constructor1
+    public BetterWallet(double money) {
+        super(money);
+    }
+
+    // method2
+    public void addMoney(int euros, int cents) {
+        // dividing by 100 can return 0 when it is less than 100
+        // -> because 'cents/100.0' would be an int
+        // this.money += euros + cents/100;
+        // divide by 100.0 for 'cents/100.0' to become a double
+        this.money += euros + cents/100.0;
+    }
+    
+    // method3
+    public void addMoney(String amount) {
+        // string to double
+        // this.money += Integer.parseInt(amount);
+        this.money += Double.parseDouble(amount);
+    }
+
+    
+}
+
+
+
+Testing class BetterWallet...
+Object created!
+Money now: 100.0
+Adding 3.75
+Money now: 103.75
+Adding 62 euros and 57 cents
+Money now: 166.32
+Adding "13.2"
+Money now: 179.51999999999998
+
+
+
+