[GSCKATA-47] Clarify and improve the exercises.

git-svn-id: svn+ssh://gsckata.svn.services.gs.com/svnroot/gsckata/trunk@117 66aded80-052e-4344-91a8-38ab96726eea

src/main/java/com/gs/collections/kata/Company.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -54,7 +54,7 @@ public MutableList<Customer> getCustomers()
 
     public MutableList<Order> getOrders()
     {
-        Assert.fail("Refactor this code to use GS Collections as part of Exercise 4");
+        Assert.fail("Refactor this code to use GS Collections as part of Exercise 3");
         MutableList<Order> orders = FastList.newList();
         for (Customer customer : this.customers)
         {
@@ -89,7 +89,7 @@ public Customer getCustomerNamed(String name)
         /**
          * Use a {@link Predicate} to find a {@link Customer} with the name given.
          */
-        Assert.fail("Implement this method as part of Exercise 3");
+        Assert.fail("Implement this method as part of Exercise 2");
         return null;
     }
 }

src/main/java/com/gs/collections/kata/Customer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,32 +30,19 @@
  */
 public class Customer
 {
-    public static final Function<Customer, String> TO_NAME = new Function<Customer, String>()
-    {
-        @Override
-        public String valueOf(Customer customer)
-        {
-            Assert.fail("Replace with the implementation of the Function.");
-            return null;
-        }
+    public static final Function<Customer, String> TO_NAME = customer -> {
+        Assert.fail("Replace with the implementation of the Function.");
+        return null;
     };
 
     public static final Function<Customer, String> TO_CITY = null;
 
-    public static final Function<Customer, Double> TO_TOTAL_ORDER_VALUE =
-            new Function<Customer, Double>()
-            {
-                @Override
-                public Double valueOf(Customer customer)
-                {
-                    return customer.getTotalOrderValue();
-                }
-            };
+    public static final Function<Customer, Double> TO_TOTAL_ORDER_VALUE = Customer::getTotalOrderValue;
 
     private final String name;
     private final String city;
 
-    private final List<Order> orders = new ArrayList<Order>();
+    private final List<Order> orders = new ArrayList<>();
 
     public Customer(String name, String city)
     {
@@ -85,14 +72,7 @@ public void addOrder(Order anOrder)
 
     public double getTotalOrderValue()
     {
-        MutableList<Double> orderValues = ListIterate.collect(this.orders, new Function<Order, Double>()
-        {
-            @Override
-            public Double valueOf(Order order)
-            {
-                return order.getValue();
-            }
-        });
+        MutableList<Double> orderValues = ListIterate.collect(this.orders, Order::getValue);
         return orderValues.injectInto(0.0, AddFunction.DOUBLE_TO_DOUBLE);
     }
 }

src/main/java/com/gs/collections/kata/LineItem.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,14 +23,7 @@
  */
 public class LineItem
 {
-    public static final Function<LineItem, String> TO_NAME = new Function<LineItem, String>()
-    {
-        @Override
-        public String valueOf(LineItem lineItem)
-        {
-            return lineItem.name;
-        }
-    };
+    public static final Function<LineItem, String> TO_NAME = LineItem::getName;
 
     private String name;
     private final double value;

src/main/java/com/gs/collections/kata/Order.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,50 +21,24 @@
 import java.util.List;
 
 import com.gs.collections.api.block.function.Function;
-import com.gs.collections.api.block.predicate.Predicate;
 import com.gs.collections.impl.block.function.AddFunction;
 import com.gs.collections.impl.collection.mutable.CollectionAdapter;
 import com.gs.collections.impl.utility.Iterate;
 
 /**
  * Has a number, a {@link Customer}, a {@link List} of {@link LineItem}s, and a boolean that states whether or not the order
- * has been delivered.  There is a class variable that contains the next order number.
+ * has been delivered. There is a class variable that contains the next order number.
  */
 public class Order
 {
-    public static final Function<Order, Double> TO_VALUE =
-            new Function<Order, Double>()
-            {
-                @Override
-                public Double valueOf(Order order)
-                {
-                    return order.getValue();
-                }
-            };
-
-    public static final Predicate<Order> IS_DELIVERED = new Predicate<Order>()
-    {
-        @Override
-        public boolean accept(Order order)
-        {
-            return order.isDelivered;
-        }
-    };
-
-    public static final Function<Order, Iterable<LineItem>> TO_LINE_ITEMS =
-            new Function<Order, Iterable<LineItem>>()
-            {
-                @Override
-                public Iterable<LineItem> valueOf(Order order)
-                {
-                    return order.lineItems;
-                }
-            };
+    public static final Function<Order, Double> TO_VALUE = Order::getValue;
+
+    public static final Function<Order, Iterable<LineItem>> TO_LINE_ITEMS = Order::getLineItems;
 
     private static int nextOrderNumber = 1;
 
     private final int orderNumber;
-    private final List<LineItem> lineItems = new ArrayList<LineItem>();
+    private final List<LineItem> lineItems = new ArrayList<>();
     private boolean isDelivered;
 
     public Order()
@@ -106,14 +80,7 @@ public String toString()
 
     public double getValue()
     {
-        Collection<Double> itemValues = Iterate.collect(this.lineItems, new Function<LineItem, Double>()
-        {
-            @Override
-            public Double valueOf(LineItem lineItem)
-            {
-                return lineItem.getValue();
-            }
-        });
+        Collection<Double> itemValues = Iterate.collect(this.lineItems, LineItem::getValue);
 
         return CollectionAdapter.adapt(itemValues).injectInto(0.0, AddFunction.DOUBLE_TO_DOUBLE);
     }

src/main/java/com/gs/collections/kata/Supplier.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,25 +23,9 @@
  */
 public class Supplier
 {
-    public static final Function<Supplier, String> TO_NAME =
-            new Function<Supplier, String>()
-            {
-                @Override
-                public String valueOf(Supplier supplier)
-                {
-                    return supplier.name;
-                }
-            };
+    public static final Function<Supplier, String> TO_NAME = Supplier::getName;
 
-    public static final Function<Supplier, Integer> TO_NUMBER_OF_ITEMS =
-            new Function<Supplier, Integer>()
-            {
-                @Override
-                public Integer valueOf(Supplier supplier)
-                {
-                    return supplier.itemNames.length;
-                }
-            };
+    public static final Function<Supplier, Integer> TO_NUMBER_OF_ITEMS = supplier -> supplier.getItemNames().length;
 
     private final String name;
     private final String[] itemNames;

src/test/java/com/gs/collections/kata/CompanyDomainForKata.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -47,14 +47,14 @@ private void setUpCustomersAndOrders()
         fredOrder.addLineItem(new LineItem("shed", 50.0));
 
         /**
-         * TODO 8: Refactor Order and its API so this repetition is not necessary.
+         * TODO 7: Refactor Order and its API so this repetition is not necessary.
          */
-        // TODO 8: Add 3 cups at 1.5 each to the order
+        // TODO 7: Add 3 cups at 1.5 each to the order
         fredOrder.addLineItem(new LineItem("cup", 1.5));
         fredOrder.addLineItem(new LineItem("cup", 1.5));
         fredOrder.addLineItem(new LineItem("cup", 1.5));
 
-        // TODO 8: Add 3 saucers at 1.0 each to the order
+        // TODO 7: Add 3 saucers at 1.0 each to the order
         fredOrder.addLineItem(new LineItem("saucer", 1.0));
         fredOrder.addLineItem(new LineItem("saucer", 1.0));
         fredOrder.addLineItem(new LineItem("saucer", 1.0));
@@ -70,13 +70,13 @@ private void setUpCustomersAndOrders()
         maryOrder.addLineItem(new LineItem("cat", 150.0));
         maryOrder.addLineItem(new LineItem("big shed", 500.0));
 
-        // TODO 8: Add 4 cups at 1.50 each to the order
+        // TODO 7: Add 4 cups at 1.50 each to the order
         maryOrder.addLineItem(new LineItem("cup", 1.5));
         maryOrder.addLineItem(new LineItem("cup", 1.5));
         maryOrder.addLineItem(new LineItem("cup", 1.5));
         maryOrder.addLineItem(new LineItem("cup", 1.5));
 
-        // TODO 8: Add 4 saucers at 1.50 each to the order
+        // TODO 7: Add 4 saucers at 1.50 each to the order
         maryOrder.addLineItem(new LineItem("saucer", 1.5));
         maryOrder.addLineItem(new LineItem("saucer", 1.5));
         maryOrder.addLineItem(new LineItem("saucer", 1.5));
@@ -92,7 +92,7 @@ private void setUpCustomersAndOrders()
         Order billOrder1 = new Order();
         billOrder1.addLineItem(new LineItem("shed", 50.0));
 
-        // TODO 8: Add 43 gnomes at 7.50 each to the order
+        // TODO 7: Add 43 gnomes at 7.50 each to the order
         for (int i = 0; i < 43; i++)
         {
             billOrder1.addLineItem(new LineItem("gnome", 7.50));

src/test/java/com/gs/collections/kata/Exercise1Test.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011 Goldman Sachs.
+ * Copyright 2015 Goldman Sachs.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,14 +28,7 @@ public class Exercise1Test extends CompanyDomainForKata
     @Test
     public void getCustomerNames()
     {
-        Function<Customer, String> nameFunction = new Function<Customer, String>()
-        {
-            @Override
-            public String valueOf(Customer customer)
-            {
-                return customer.getName();
-            }
-        };
+        Function<Customer, String> nameFunction = Customer::getName;
 
         /**
          * Get the name of each of the company's customers.
@@ -51,9 +44,7 @@ public String valueOf(Customer customer)
     public void getCustomerCities()
     {
         /**
-         * Get the city for each of the company's customers. Use an anonymous inner class. Use the IDE to help you as
-         * much as possible. Ctrl+space will help you implement an anonymous inner class. Implementing an interface is
-         * ctrl+i in IntelliJ. Eclipse's ctrl+1 is auto-fix and works to implement interfaces.
+         * Get the city for each of the company's customers.
          */
         MutableList<Customer> customers = this.company.getCustomers();
         MutableList<String> customerCities = null;
@@ -66,7 +57,7 @@ public void getCustomerCities()
     public void getLondonCustomers()
     {
         /**
-         * Which customers come from London? Get a collection of those which do. Use an anonymous inner class.
+         * Which customers come from London? Get a collection of those which do.
          */
         MutableList<Customer> customers = this.company.getCustomers();
         MutableList<Customer> customersFromLondon = null;