Naive

TicketMachine.java

@@ -12,7 +12,7 @@
 public class TicketMachine
 {
     // The price of a ticket from this machine.
-    private int price;
+    private int price = 500;
     // The amount of money entered by a customer so far.
     private int balance;
     // The total amount of money collected by this machine.
@@ -25,7 +25,7 @@ public class TicketMachine
      */
     public TicketMachine(int ticketCost)
     {
-        price = ticketCost;
+        int price = ticketCost;
         balance = 0;
         total = 0;
     }
@@ -52,7 +52,13 @@ public class TicketMachine
      */
     public void insertMoney(int amount)
     {
-        balance = balance + amount;
+        if(amount > 0) {
+            balance = balance + amount;
+        }
+        else {
+            System.out.println("Use a positive amount: " +
+                amount);
+        }
     }
 
     /**
@@ -62,17 +68,40 @@ public class TicketMachine
      */
     public void printTicket()
     {
-        // Simulate the printing of a ticket.
-        System.out.println("##################");
-        System.out.println("# The BlueJ Line");
-        System.out.println("# Ticket");
-        System.out.println("# " + price + " cents.");
-        System.out.println("##################");
-        System.out.println();
+        if(balance >= price) {
+            // Simulate the printing of a ticket.
+            System.out.println("##################");
+            System.out.println("# The BlueJ Line");
+            System.out.println("# Ticket");
+            System.out.println("# " + price + " cents.");
+            System.out.println("##################");
+            System.out.println();
+            // Update the total collected with the price.
+            total = total + price;
+            // Reduce the balance by the price.
+            balance = balance - price;
+        }
+        else {
+            System.out.println("You must insert at least: " +
+                (price - balance) + " more cents.");
+        }
+    }
+    
+    public void showPrice() 
+    {
+        System.out.println("The price of a ticket is " + price + " cents.");
+    }
 
-        // Update the total collected with the balance.
-        total = total + balance;
-        // Clear the balance.
+    /**
+     * Return the money in the balance.
+     * The balance is cleared.
+     */
+    public int refundBalance()
+    {
+        int amountToRefund;
+        amountToRefund = balance;
         balance = 0;
+        return amountToRefund;
     }
+
 }

bluej.pkg

@@ -1,16 +1,16 @@
 #BlueJ package file
-editor.fx.0.height=722
-editor.fx.0.width=800
-editor.fx.0.x=709
-editor.fx.0.y=113
-objectbench.height=101
+editor.fx.0.height=721
+editor.fx.0.width=1280
+editor.fx.0.x=0
+editor.fx.0.y=23
+objectbench.height=164
 objectbench.width=461
 package.divider.horizontal=0.6
-package.divider.vertical=0.8007380073800738
-package.editor.height=427
+package.divider.vertical=0.6845018450184502
+package.editor.height=364
 package.editor.width=674
-package.editor.x=1067
-package.editor.y=119
+package.editor.x=249
+package.editor.y=108
 package.frame.height=600
 package.frame.width=800
 package.numDependencies=0

package.bluej

@@ -1,16 +1,16 @@
 #BlueJ package file
-editor.fx.0.height=722
-editor.fx.0.width=800
-editor.fx.0.x=709
-editor.fx.0.y=113
-objectbench.height=101
+editor.fx.0.height=721
+editor.fx.0.width=1280
+editor.fx.0.x=0
+editor.fx.0.y=23
+objectbench.height=164
 objectbench.width=461
 package.divider.horizontal=0.6
-package.divider.vertical=0.8007380073800738
-package.editor.height=427
+package.divider.vertical=0.6845018450184502
+package.editor.height=364
 package.editor.width=674
-package.editor.x=1067
-package.editor.y=119
+package.editor.x=249
+package.editor.y=108
 package.frame.height=600
 package.frame.width=800
 package.numDependencies=0