init

.gitignore

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+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff:
+.idea/**
+.idea/**/tasks.xml
+.idea/dictionaries
+
+# Sensitive or high-churn files:
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.xml
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+
+# Gradle:
+.idea/**/gradle.xml
+.idea/**/libraries
+
+*.iml
+# CMake
+cmake-build-debug/
+
+# Mongo Explorer plugin:
+.idea/**/mongoSettings.xml
+
+## File-based project format:
+*.iws
+
+## Plugin-specific files:
+
+# IntelliJ
+/out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+.project
+.classpath
+.settings
+target

README.md

+# Store Lab
+* **Purpose** - to understand [HashMap](https://www.youtube.com/watch?v=shs0KM3wKv8), [objects](https://docs.oracle.com/javase/tutorial/java/concepts/object.html) and [data encapsulation](https://en.wikipedia.org/wiki/Data_encapsulation).
+
+* **Objective** - to create two type of maps
+
+## Part 1 - Equals & HashCode
+By default, every [Java object](https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html) has an [equals](https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#equals) and a [hashCode](https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#hashCode) method. Java uses the object's address to calculate the [hashCode](https://en.wikipedia.org/wiki/Hash_function). By default, two objects are equal if they have the same address. We don't want this. Two objects are equal if they are the same class and have the same values.
+
+  1. User
+    1. Add an `equals` method to the `User` class. The equal method should return true only if the `id` and `name` of the user are the same. It return false otherwise.
+    2. Add a `hashCode` method by calling `Objects.hash()` and gives it the `id` and `name` (e.g. `Objects.hash(id, name)`)
+  2. Cart
+    1. Add an `equals` and `hashCode` methods with IntelliJ shortcut
+      1. Click `Command + N` and select `equals and hashCode`. Follow the wizard to generate the code.
+
+## Part 2 - ListMap
+
+
+
+
+This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the JavaTM programming language
+
+
+## Part 1 - ListMap
+In the `test` folder, there is a `ProductTest` with most of the tested commented out.
+  1. The first test `testConstruction_WithNoParams` checks to see if the `Product` class has an empty constructor. To test it, I created a new object with no parameter.
+  2. The second test `testGetSetName` checks to see if you can set and get the name of the product. In order to make this pass, I added a `String` field called `name` (line 5). Then I added a getter method `getName` (line 18-20) and a setter method `setName(String name)` (line 23-25).
+  3. The third test `testConstruction_WithName` checks if the `Product` class has a constructor that takes a String. Notice we can have more than one constructor. When I create a new Product with a string `new Product("T-shirt")`, I set that string to the field `name` so when I called `getName`, I get the string that I passed into the constructor.
+  4. Continue to uncomment the test and write the code to make it pass
+  5. For the product description, it should be in this format `title (Color: color, Size: size)`
+    - ex: `Hat (Color: Yellow, Size: LG)`
+
+## Part 2 - Cart
+A cart has an array of Product.
+  1. Open the `CartTest` and uncomment line 9-13. To make the test pass:
+    - Create a new class named `Cart`
+    - Create a new constructor that takes an array of Product
+    - Run the test, it should pass
+  2. Create a getter for Product to make `testGetProducts` test pass
+  3. To make `testGetSetDiscount` test pass:
+    - Create a new decimal field called `discount`
+    - Create a getter and setter for the field
+    - Run the test
+  4. To get `getProductTotal` tests to pass, you need add all the product prices together and return the result.
+  5. To get the total, you need to add the total of all the products minus the discount. For example, if a product costs $100, and the discount is 20% (0.20), then the total = 100 - (100 * 0.20) = 80
+
+## Part 3 - CreditCard
+The goal of this exercise is to know how to create and test a class.
+  1. In the test folder, create a new test class called `CreditCardTest`
+  2. Create a new class called `CreditCard`
+  2. Create a test case to get and set the `cardHolderName` of the type `String`
+      - Create getter and setter methods in the `CreditCard` class
+      - Add a field called cardHolderName
+  2. Do the same for the following fields:
+    - `String number`
+    - `int expiredMonth`
+    - `int expiredYear`
+  3. Create a getter and setter for each field
+  4. Create a test for `getDescription`
+    - `getDescription` should return `[cardHolderName] [last 4 digit of the number] [expiredMonth]/[expiredYear]`
+      - ex: `Tia Mowry 4551 10/2019`
+  5. Add a `CreditCard` field to the `Cart` class
+    - Add a getter and setter for the `creditCard` field
+
+## Part 4 - Product as an ArrayList - BONUS
+The goal of this exercise is to change the `products` array in the `Cart` class to an ArrayList.
+  1. In the `CartTest`, change the `products` array to an `ArrayList`
+
+    ```java
+      ArrayList<Product> products = new ArrayList();
+      products.add(new Product("Shirt", 15.01));
+    ```
+
+  2. Add this test to the `CartTest` class
+  ```java
+    @Test
+    public void testAddToCard(){
+        // Given
+        ArrayList<Product> products = new ArrayList();
+        Cart cart = new Cart(products);
+
+        // When
+        Product shirt = new Product("Shirt", 1.99);
+        cart.addProduct(shirt);
+
+        // Then
+        double expectedTotal = 1.99;
+        double actualTotal = cart.getProductTotal();
+        Assert.assertEquals(expectedTotal, actualTotal, DELTA);
+    }
+  ```
+    - Add a `addProduct` method to the `Cart` class
+    - Run the test. It should pass.

pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.zipcoder</groupId>
+    <artifactId>Store-Hash</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+
+</project>

src/test/java/org/zipcoder/store/CartTest.java

+package org.zipcoder.store;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class CartTest {
+
+    @Test
+    public void testGetSetId(){
+        // Given
+        long expectedId = 931;
+        Cart cart1 = new Cart(expectedId);
+
+        // When
+        long actualId = cart1.getId();
+
+        // Then
+        Assert.assertEquals(expectedId, actualId);
+    }
+
+    @Test
+    public void testEquals_CartWithTheSameIdAreEquals(){
+        // Given
+        long id = 111;
+        Cart cart1 = new Cart(id);
+        Cart copyCart1 = new Cart(id);
+
+        // When
+        boolean equality = cart1.equals(copyCart1);
+
+        // Then
+        Assert.assertTrue(equality);
+    }
+
+    @Test
+    public void testHashCode_CartWithTheSameIdAreHaveTheSameHash(){
+        // Given
+        long id = 111;
+        Cart cart1 = new Cart(id);
+        Cart copyCart1 = new Cart(id);
+
+        // When
+        int cart1Hash = cart1.hashCode();
+        int copyCart1Hash = copyCart1.hashCode();
+
+        // Then
+        Assert.assertEquals(cart1Hash, copyCart1Hash);
+    }
+}

src/test/java/org/zipcoder/store/ListMapTest.java

+package org.zipcoder.store;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.List;
+
+public class ListMapTest {
+    private MyMap myMap;
+
+    @Before
+    public void setup(){
+        myMap = new ListMap();
+    }
+
+    @Test
+    public void testPutAndGet_WithOneItem(){
+        User user = new User("Tiana");
+        Cart cart = new Cart(1);
+
+        // When
+        myMap.put(user, cart);
+
+        // Then
+        Cart actualCart = myMap.get(user);
+        Assert.assertEquals(cart, actualCart);
+    }
+
+    @Test
+    public void testPutAndGet_WithTwoItems(){
+        User tiana = new User("Tiana");
+        Cart tianasCart = new Cart(1134);
+
+        User john = new User("John");
+        Cart johnsCart = new Cart(42);
+
+        // When
+        myMap.put(john, johnsCart);
+        myMap.put(tiana, tianasCart);
+
+        // Then
+        Cart actualJohnsCart = myMap.get(john);
+        Assert.assertEquals(johnsCart, actualJohnsCart);
+
+        Cart actualTianasCart = myMap.get(tiana);
+        Assert.assertEquals(tianasCart, actualTianasCart);
+    }
+
+    @Test
+    public void testPutAndGet_UpdateCart(){
+        User tiana = new User("Tiana");
+        Cart tianasCart = new Cart(11);
+        myMap.put(tiana, tianasCart);
+
+        // When
+        Cart updatedCart = new Cart(99);
+        myMap.put(tiana, updatedCart);
+
+        // Then
+        Cart actualCart = myMap.get(tiana);
+        Assert.assertEquals(updatedCart, actualCart);
+    }
+
+    @Test
+    public void testGetWithoutPut(){
+        // Given
+        User user = new User("Tiana");
+
+        // When
+        Cart actualCart = myMap.get(user);
+
+        // Then
+        Assert.assertNull(actualCart);
+    }
+
+    @Test
+    public void testPutAndGet_WithDifferentKeyInstance(){
+        // Given
+        String name = "Tiana";
+        User tiana = new User(name);
+        Cart cart = new Cart(76);
+
+        // When
+        myMap.put(tiana, cart);
+        User cloneTiana = new User(name);
+        Cart actualCart = myMap.get(cloneTiana);
+
+        // Then
+        Assert.assertEquals(cart, actualCart);
+    }
+
+    @Test
+    public void testSize_WithNoEntry(){
+        int expectedSize = 0;
+        Assert.assertEquals(expectedSize, myMap.size());
+    }
+
+    @Test
+    public void testSize_WithEntries(){
+        // Given
+        User user1 = new User("Monica");
+        Cart cart1 = new Cart(45);
+
+        User user2 = new User("Quincy");
+        Cart cart2 = new Cart(78);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+
+        // Then
+        int expectedSize = 2;
+        Assert.assertEquals(expectedSize, myMap.size());
+    }
+
+    @Test
+    public void testIsEmpty_WithoutEntry(){
+        Assert.assertTrue(myMap.isEmptry());
+    }
+
+    @Test
+    public void testisEmpty_WithEntries(){
+        // Given
+        User user1 = new User("Monica");
+        Cart cart1 = new Cart(45);
+
+        // When
+        myMap.put(user1, cart1);
+
+        // Then
+        Assert.assertFalse(myMap.isEmptry());
+    }
+
+    @Test
+    public void testGetKeys(){
+        // Given
+        User user1 = new User("Zeke");
+        Cart cart1 = new Cart(7);
+
+        User user2 = new User("Nona");
+        Cart cart2 = new Cart(29);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+
+        // Then
+        List<User> keys = myMap.getKeys();
+        int expectedKeySize = 2;
+        Assert.assertEquals(expectedKeySize, keys.size());
+        Assert.assertTrue(keys.contains(user1));
+        Assert.assertTrue(keys.contains(user2));
+    }
+
+    @Test
+    public void testGetValues(){
+        // Given
+        User user1 = new User("Camille");
+        Cart cart1 = new Cart(433);
+
+        User user2 = new User("Nathan");
+        Cart cart2 = new Cart(71);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+
+        // Then
+        List<Cart> values = myMap.getValues();
+        int expectedKeySize = 2;
+        Assert.assertEquals(expectedKeySize, values.size());
+        Assert.assertTrue(values.contains(cart1));
+        Assert.assertTrue(values.contains(cart2));
+    }
+
+    @Test
+    public void testPutAndGet_WithManyItems(){
+        // Given
+        for (int i = 0; i < 70000; i++) {
+            myMap.put(new User(i), new Cart(i));
+        }
+
+
+        for (int i = 0; i < 70000; i++) {
+            // When
+            Cart actualCart = myMap.get(new User(i));
+            Cart expectedCart = new Cart(i);
+
+            // Then
+            Assert.assertEquals(actualCart, expectedCart);
+        }
+    }
+
+    @Test
+    public void testRemove(){
+        // Given
+        User user1 = new User("Lena");
+        Cart cart1 = new Cart(11);
+
+        User user2 = new User("Jamal");
+        Cart cart2 = new Cart(21);
+
+        User user3 = new User("Kelvin");
+        Cart cart3 = new Cart(31);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+        myMap.put(user3, cart3);
+
+        // Then
+        Cart actualCart = myMap.remove(user2);
+
+        Assert.assertEquals(cart2, actualCart);
+        Assert.assertNull(myMap.get(user2));
+    }
+
+    @Test
+    public void testRemove_CartNotInTheMap(){
+        // Given
+        User user1 = new User("Lena");
+
+        // When & Then
+        Assert.assertNull(myMap.remove(user1));
+    }
+}

src/test/java/org/zipcoder/store/MyHashMapTest.java

+package org.zipcoder.store;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.List;
+
+public class MyHashMapTest {
+    private MyMap myMap;
+
+    @Before
+    public void setup(){
+        myMap = new MyHashMap();
+    }
+
+    @Test
+    public void testPutAndGet_WithOneItem(){
+        User user = new User("Tiana");
+        Cart cart = new Cart(1);
+
+        // When
+        myMap.put(user, cart);
+
+        // Then
+        Cart actualCart = myMap.get(user);
+        Assert.assertEquals(cart, actualCart);
+    }
+
+    @Test
+    public void testPutAndGet_WithTwoItems(){
+        User tiana = new User("Tiana");
+        Cart tianasCart = new Cart(1134);
+
+        User john = new User("John");
+        Cart johnsCart = new Cart(42);
+
+        // When
+        myMap.put(john, johnsCart);
+        myMap.put(tiana, tianasCart);
+
+        // Then
+        Cart actualJohnsCart = myMap.get(john);
+        Assert.assertEquals(johnsCart, actualJohnsCart);
+
+        Cart actualTianasCart = myMap.get(tiana);
+        Assert.assertEquals(tianasCart, actualTianasCart);
+    }
+
+    @Test
+    public void testPutAndGet_UpdateCart(){
+        User tiana = new User("Tiana");
+        Cart tianasCart = new Cart(11);
+        myMap.put(tiana, tianasCart);
+
+        // When
+        Cart updatedCart = new Cart(99);
+        myMap.put(tiana, updatedCart);
+
+        // Then
+        Cart actualCart = myMap.get(tiana);
+        Assert.assertEquals(updatedCart, actualCart);
+    }
+
+    @Test
+    public void testGetWithoutPut(){
+        // Given
+        User user = new User("Tiana");
+
+        // When
+        Cart actualCart = myMap.get(user);
+
+        // Then
+        Assert.assertNull(actualCart);
+    }
+
+    @Test
+    public void testPutAndGet_WithDifferentKeyInstance(){
+        // Given
+        String name = "Tiana";
+        User tiana = new User(name);
+        Cart cart = new Cart(76);
+
+        // When
+        myMap.put(tiana, cart);
+        User cloneTiana = new User(name);
+        Cart actualCart = myMap.get(cloneTiana);
+
+        // Then
+        Assert.assertEquals(cart, actualCart);
+    }
+
+    @Test
+    public void testSize_WithNoEntry(){
+        int expectedSize = 0;
+        Assert.assertEquals(expectedSize, myMap.size());
+    }
+
+    @Test
+    public void testSize_WithEntries(){
+        // Given
+        User user1 = new User("Monica");
+        Cart cart1 = new Cart(45);
+
+        User user2 = new User("Quincy");
+        Cart cart2 = new Cart(78);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+
+        // Then
+        int expectedSize = 2;
+        Assert.assertEquals(expectedSize, myMap.size());
+    }
+
+    @Test
+    public void testIsEmpty_WithoutEntry(){
+        Assert.assertTrue(myMap.isEmptry());
+    }
+
+    @Test
+    public void testisEmpty_WithEntries(){
+        // Given
+        User user1 = new User("Monica");
+        Cart cart1 = new Cart(45);
+
+        // When
+        myMap.put(user1, cart1);
+
+        // Then
+        Assert.assertFalse(myMap.isEmptry());
+    }
+
+    @Test
+    public void testGetKeys(){
+        // Given
+        User user1 = new User("Zeke");
+        Cart cart1 = new Cart(7);
+
+        User user2 = new User("Nona");
+        Cart cart2 = new Cart(29);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+
+        // Then
+        List<User> keys = myMap.getKeys();
+        int expectedKeySize = 2;
+        Assert.assertEquals(expectedKeySize, keys.size());
+        Assert.assertTrue(keys.contains(user1));
+        Assert.assertTrue(keys.contains(user2));
+    }
+
+    @Test
+    public void testGetValues(){
+        // Given
+        User user1 = new User("Camille");
+        Cart cart1 = new Cart(433);
+
+        User user2 = new User("Nathan");
+        Cart cart2 = new Cart(71);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+
+        // Then
+        List<Cart> values = myMap.getValues();
+        int expectedKeySize = 2;
+        Assert.assertEquals(expectedKeySize, values.size());
+        Assert.assertTrue(values.contains(cart1));
+        Assert.assertTrue(values.contains(cart2));
+    }
+
+    @Test
+    public void testPutAndGet_WithManyItems(){
+        // Given
+        for (int i = 0; i < 70000; i++) {
+            myMap.put(new User(i), new Cart(i));
+        }
+
+
+        for (int i = 0; i < 70000; i++) {
+            // When
+            Cart actualCart = myMap.get(new User(i));
+            Cart expectedCart = new Cart(i);
+
+            // Then
+            Assert.assertEquals(actualCart, expectedCart);
+        }
+    }
+
+    @Test
+    public void testRemove(){
+        // Given
+        User user1 = new User("Lena");
+        Cart cart1 = new Cart(11);
+
+        User user2 = new User("Jamal");
+        Cart cart2 = new Cart(21);
+
+        User user3 = new User("Kelvin");
+        Cart cart3 = new Cart(31);
+
+        // When
+        myMap.put(user1, cart1);
+        myMap.put(user2, cart2);
+        myMap.put(user3, cart3);
+
+        // Then
+        Cart actualCart = myMap.remove(user2);
+
+        Assert.assertEquals(cart2, actualCart);
+        Assert.assertNull(myMap.get(user2));
+    }
+
+    @Test
+    public void testRemove_CartNotInTheMap(){
+        // Given
+        User user1 = new User("Lena");
+
+        // When & Then
+        Assert.assertNull(myMap.remove(user1));
+    }
+}

src/test/java/org/zipcoder/store/UserTest.java

+package org.zipcoder.store;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class UserTest {
+    private User user;
+
+    @Before
+    public void setup(){
+        user = new User();
+    }
+
+    @Test
+    public void testGetSetName(){
+        // Given
+        String expectedName = "Tiana";
+        user.setName(expectedName);
+
+        // When
+        String actualName = user.getName();
+
+        // Then
+        Assert.assertEquals(expectedName, actualName);
+    }
+
+    @Test
+    public void testGetSetId(){
+        // Given
+        long expectedId = 1133;
+        user.setId(expectedId);
+
+        // When
+        long actualId = user.getId();
+
+        // Then
+        Assert.assertEquals(expectedId, actualId);
+    }
+
+    @Test
+    public void testEqual_withDefaultFields(){
+        User user1 = new User();
+        User user2 = new User();
+
+        Assert.assertTrue(user1.equals(user2));
+    }
+
+    @Test
+    public void testEqual_withSameIdAndNoName(){
+        long id = 73;
+        User user1 = new User(id);
+        User user2 = new User(id);
+
+        Assert.assertTrue(user1.equals(user2));
+    }
+
+    @Test
+    public void testEqual_withSameIdAndDifferentName(){
+        long id = 613;
+        User user1 = new User(id, "Jonas");
+        User user2 = new User(id, "Fiona");
+
+        Assert.assertFalse(user1.equals(user2));
+    }
+
+    @Test
+    public void testEqual_withSameNameDifferentId(){
+        String name = "Asher";
+        User user1 = new User(92, name);
+        User user2 = new User(87, name);
+
+        Assert.assertFalse(user1.equals(user2));
+    }
+
+    @Test
+    public void testEqual_withSameIdAndSameName(){
+        long id = 613;
+        String name = "Asher";
+        User user1 = new User(id, name);
+        User user2 = new User(id, name);
+
+        Assert.assertTrue(user1.equals(user2));
+    }
+
+    @Test
+    public void testHashCode_withDefaultFields(){
+        User user1 = new User();
+        User user2 = new User();
+
+        Assert.assertEquals(user1.hashCode(), user2.hashCode());
+    }
+
+    @Test
+    public void testHashCode_withSameIdAndNoName(){
+        long id = 124;
+        User user1 = new User(id);
+        User user2 = new User(id);
+
+        Assert.assertEquals(user1.hashCode(), user2.hashCode());
+    }
+
+    @Test
+    public void testHashCode_withSameIdAndDifferentName(){
+        long id = 57;
+        User user1 = new User(id, "Jonas");
+        User user2 = new User(id, "Fiona");
+
+        Assert.assertNotEquals(user1.hashCode(), user2.hashCode());
+    }
+
+    @Test
+    public void testHashCode_withSameNameDifferentId(){
+        String name = "Asher";
+        User user1 = new User(11, name);
+        User user2 = new User(22, name);
+
+        Assert.assertNotEquals(user1.hashCode(), user2.hashCode());
+    }
+
+    @Test
+    public void testHashCode_withSameIdAndSameName(){
+        long id = 33;
+        String name = "Asher";
+        User user1 = new User(id, name);
+        User user2 = new User(id, name);
+
+        Assert.assertEquals(user1.hashCode(), user2.hashCode());
+    }
+}