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completed lab

Allison Ziegler 6 年之前
父節點
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f16c5ad803
共有 2 個檔案被更改,包括 99 行新增60 行删除
  1. 47
    8
      src/main/java/org/zipcoder/store/MyHashMap.java
  2. 52
    52
      src/test/java/org/zipcoder/store/MyHashMapTest.java

+ 47
- 8
src/main/java/org/zipcoder/store/MyHashMap.java 查看文件

@@ -4,7 +4,7 @@ import java.util.*;
4 4
 
5 5
 public class MyHashMap implements MyMap{
6 6
     // final field that doesn't change for any object
7
-    private static final int BUCKET_SIZE = 15;
7
+    private static final int BUCKET_SIZE = 100;
8 8
 
9 9
     // instance field that can only be set once. It is different for every Object
10 10
     private final List<Entry>[] entries;
@@ -19,40 +19,79 @@ public class MyHashMap implements MyMap{
19 19
 
20 20
     @Override
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     public int size() {
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-        return -1;
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+        int count = 0;
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+        for (List<Entry> list : entries) {
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+            count += list.size();
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+        }
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+        return count;
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     }
24 28
 
25 29
     @Override
26 30
     public boolean isEmptry() {
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-        return false;
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+        if (size() == 0) return true;
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+        else return false;
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     }
29 34
 
30 35
     @Override
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     public Cart get(User key) {
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-        return null;
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+        List<Entry> bucket = entries[bucketIndex(key)];
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+        int index = keyIndex(bucket, key);
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+        if (index >= 0 ) return bucket.get(keyIndex(bucket, key)).getValue();
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+        else return null;
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     }
34 42
 
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     @Override
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     public void put(User key, Cart value) {
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-
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+        entries[bucketIndex(key)].add(new Entry(key, value));
38 46
     }
39 47
 
40 48
     @Override
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     public List<User> getKeys() {
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-        return null;
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+        List<User> keys = new ArrayList<User>();
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+        for (List<Entry> list : entries) {
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+            for (Entry e : list) {
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+                keys.add(e.getKey());
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+            }
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+        }
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+        return keys;
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     }
44 58
 
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     @Override
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     public List<Cart> getValues() {
47
-        return null;
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+        List<Cart> values = new ArrayList<Cart>();
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+        for (List<Entry> list : entries) {
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+            for (Entry e : list) {
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+                values.add(e.getValue());
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+            }
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+        }
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+        return values;
48 68
     }
49 69
 
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     @Override
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     public Cart remove(User key) {
52
-        return null;
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+        List<Entry> bucket = entries[bucketIndex(key)];
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+        Iterator<Entry> iterator = bucket.iterator();
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+        Cart removed = null;
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+        while(iterator.hasNext()) {
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+            Entry entry = iterator.next();
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+            if (entry.getKey().equals(key)) {
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+                removed = entry.getValue();
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+                iterator.remove();
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+            }
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+        }
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+        return removed;
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     }
54 84
 
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     private int bucketIndex(User key){
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         return Math.abs(key.hashCode()) % entries.length;
57 87
     }
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+    private int keyIndex(List<Entry> bucket, User key) {
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+        int index = -1;
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+        for (int i = 0; i < bucket.size(); i++) {
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+            if (bucket.get(i).getKey().equals(key)) {
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+                index = i;
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+            }
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+        }
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+        return index;
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+    }
58 97
 }

+ 52
- 52
src/test/java/org/zipcoder/store/MyHashMapTest.java 查看文件

@@ -175,56 +175,56 @@ public class MyHashMapTest {
175 175
     }
176 176
 
177 177
 //    I commented this out because it takes a long time to run. Uncomment it when implement your put method, uncomment this test
178
-//    @Test
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-//    public void testPutAndGet_WithManyItems(){
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-//        // Given
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-//        int numberOfEntries = 70000;
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-//
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-//        for (int i = 0; i < numberOfEntries; i++) {
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-//            myMap.put(new User(i), new Cart(i));
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-//        }
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-//
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-//
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-//        for (int i = 0; i < numberOfEntries; i++) {
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-//            // When
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-//            Cart actualCart = myMap.get(new User(i));
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-//            Cart expectedCart = new Cart(i);
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-//
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-//            // Then
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-//            Assert.assertEquals(actualCart, expectedCart);
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-//        }
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-//    }
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-
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-//    @Test
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-//    public void testRemove(){
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-//        // Given
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-//        User user1 = new User("Lena");
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-//        Cart cart1 = new Cart(11);
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-//
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-//        User user2 = new User("Jamal");
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-//        Cart cart2 = new Cart(21);
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-//
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-//        User user3 = new User("Kelvin");
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-//        Cart cart3 = new Cart(31);
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-//
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-//        // When
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-//        myMap.put(user1, cart1);
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-//        myMap.put(user2, cart2);
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-//        myMap.put(user3, cart3);
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-//
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-//        // Then
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-//        Cart actualCart = myMap.remove(user2);
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-//
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-//        Assert.assertEquals(cart2, actualCart);
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-//        Assert.assertNull(myMap.get(user2));
220
-//    }
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-//
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-//    @Test
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-//    public void testRemove_CartNotInTheMap(){
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-//        // Given
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-//        User user1 = new User("Lena");
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-//
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-//        // When & Then
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-//        Assert.assertNull(myMap.remove(user1));
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-//    }
178
+    @Test
179
+    public void testPutAndGet_WithManyItems(){
180
+        // Given
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+        int numberOfEntries = 70000;
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+
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+        for (int i = 0; i < numberOfEntries; i++) {
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+            myMap.put(new User(i), new Cart(i));
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+        }
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+
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+
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+        for (int i = 0; i < numberOfEntries; i++) {
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+            // When
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+            Cart actualCart = myMap.get(new User(i));
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+            Cart expectedCart = new Cart(i);
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+
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+            // Then
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+            Assert.assertEquals(actualCart, expectedCart);
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+        }
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+    }
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+
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+    @Test
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+    public void testRemove(){
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+        // Given
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+        User user1 = new User("Lena");
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+        Cart cart1 = new Cart(11);
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+
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+        User user2 = new User("Jamal");
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+        Cart cart2 = new Cart(21);
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+
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+        User user3 = new User("Kelvin");
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+        Cart cart3 = new Cart(31);
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+
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+        // When
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+        myMap.put(user1, cart1);
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+        myMap.put(user2, cart2);
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+        myMap.put(user3, cart3);
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+
215
+        // Then
216
+        Cart actualCart = myMap.remove(user2);
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+
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+        Assert.assertEquals(cart2, actualCart);
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+        Assert.assertNull(myMap.get(user2));
220
+    }
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+
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+    @Test
223
+    public void testRemove_CartNotInTheMap(){
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+        // Given
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+        User user1 = new User("Lena");
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+
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+        // When & Then
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+        Assert.assertNull(myMap.remove(user1));
229
+    }
230 230
 }