ahinkson0342 - Andrew Hinkson

LetterInventory.iml

@@ -24,5 +24,31 @@
         <SOURCES />
       </library>
     </orderEntry>
+    <orderEntry type="module-library" scope="TEST">
+      <library name="JUnit4">
+        <CLASSES>
+          <root url="jar://$MAVEN_REPOSITORY$/junit/junit/4.13.1/junit-4.13.1.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/hamcrest/hamcrest-core/1.3/hamcrest-core-1.3.jar!/" />
+        </CLASSES>
+        <JAVADOC />
+        <SOURCES />
+      </library>
+    </orderEntry>
+    <orderEntry type="module-library" scope="TEST">
+      <library name="JUnit5.8.1">
+        <CLASSES>
+          <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter/5.8.1/junit-jupiter-5.8.1.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.8.1/junit-jupiter-api-5.8.1.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-commons/1.8.1/junit-platform-commons-1.8.1.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/apiguardian/apiguardian-api/1.1.2/apiguardian-api-1.1.2.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-params/5.8.1/junit-jupiter-params-5.8.1.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-engine/5.8.1/junit-jupiter-engine-5.8.1.jar!/" />
+          <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.8.1/junit-platform-engine-1.8.1.jar!/" />
+        </CLASSES>
+        <JAVADOC />
+        <SOURCES />
+      </library>
+    </orderEntry>
   </component>
 </module>

src/inventory/LetterInventory.java

@@ -31,47 +31,61 @@ public LetterInventory(){
    * and adds each character in the text to the inventory
    * @param text
    */
+  //Fills the elements of the inventory array by looping through a string parameter
   public LetterInventory(String text) {
-   //TODO
+    this();
+    for (int i = 0; i < text.length(); i++) {
+      add(text.charAt(i));
+    }
   }
 
   /**
    * Identifies the index for the given character within the inventory array , throws an
-   * IIegalArgumentException if the character is not in the a-z or A-Z range.
+   * IllegalArgumentException if the character is not in the a-z or A-Z range.
    * For example: if the given character is 'c' or 'C', then the index returned is 2
    *              if the given character is '?', then an IllegalArgumentException is thrown
    *
    * @param c a-z or A-Z character
    * @return index of the character
    */
+  //Gets the index where a character c would belong within the inventory array, which
+  // is 26 elements in alphabetical order. if the given character is not an alpha character,
+  // it throws an IllegalArgumentException.
   public int getIndex(char c) {
-  //TODO
-    return 0;
+    if((int)Character.toLowerCase(c) >=97 && (int)Character.toLowerCase(c) <= 122) {
+      return (int) Character.toLowerCase(c) - 'a';
+    }
+    else
+    {
+      throw new IllegalArgumentException("Please enter a valid input (a-z)");
+    }
   }
 
   /**
    * Increases the count for the given character in the inventory
    * @param c a-z or A-Z otherwise an IllegalArgumentException is thrown
    */
+  //Adds a given character c to increment the appropriate index in the inventory array
   public void add(char c) {
-//TODO
+    inventory[getIndex(c)]++;
   }
 
   /**
    * Decreases the count for the given character in the inventory
    * @param c a-z or A-Z otherwise an IllegalArgumentException is thrown
    */
+  //decrements the appropriate index for the given character c within the inventory array
   public void subtract(char c) {
-  //TODO
+    inventory[getIndex(c)]--;
   }
 
   /**
    * Returns the count for the given character in the inventory
    * @param c a-z or A-Z otherwise an IllegalArgumentException is thrown
    */
+  //gets the index of a given character c
   public int get(char c) {
-   //TODO
-    return 0;
+    return inventory[getIndex(c)];
   }
 
   /**
@@ -80,36 +94,50 @@ public int get(char c) {
    * @param count the number of occurrences of the character c; if count < 0
    *              IllegalArgumentException is thrown
    */
+  //sets the value of the index for a given character c to a value "count" given as a parameter. If the character is
+  //not alpha or if the count is less than 0, it throws an IllegalArgumentException
   public void set(char c, short count) {
-    //TODO
+    if((int)Character.toLowerCase(c) >=97 && (int)Character.toLowerCase(c) <= 122 && count>=0)
+    {
+      inventory[getIndex(c)] = count;
+    }
+    else
+    {
+      throw new IllegalArgumentException("Please enter a valid input (a-z) and count must be a positive integer.");
+    }
   }
 
   /**
    * Determines if a character's count is in the inventory
    * @param c a-z or A-Z otherwise an IllegalArgumentException is thrown
    * @return true if character is in inventory, false otherwise
    */
+  //Finds the given character c within the inventory array, and returns the index of it.
   public boolean contains(char c) {
-    //TODO
-    return false;
+    return inventory[getIndex(c)] > 0;
   }
 
   /**
    * Return the total count of all letters in the inventory
    * @return total count
    */
+  //returns the size of the string that was passed in
   public int size() {
-   //TODO
-    return 0;
+    short count = 0;
+    for (int i = 0; i < inventory.length; i++)
+    {
+      count += inventory[i];
+    }
+    return count;
   }
 
   /**
    * Determine if the inventory has zero counts for all letters
    * @return true, if empty, false otherwise
    */
+  //checks if the string that was originally passed in is empty
   public boolean isEmpty() {
-    // TODO
-    return false;
+      return size() == 0;
   }
 
   /**

src/inventory/LetterPresence.java

@@ -0,0 +1,52 @@
+package inventory;
+
+/*
+ * [2,0,0,0,1,0,1,1,1,0,0,0,0,2,1,0,0,0,2,3,0,0,1,0,0,0] --> inventory count array
+ * [a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z] --> corresponding letters
+ *
+ * [1,0,0,0,1,0,1,1,1,0,0,0,0,1,1,0,0,0,1,1,0,0,1,0,0,0] --> presence count array
+ * [a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z] --> corresponding letters
+ *
+ * can use an int to represent this -- bitwise ops
+ * zyxwvutsrqponmlkjihgfedcba
+ * 00010011000110000111010001 -- some bits left off of start since we are only using 26
+ */
+
+public class LetterPresence {
+    private int inventory;
+
+    public int getIndex(char letter)
+    {
+        //assume letter is valid and lowercase
+        return letter - 'a';
+    }
+
+    public void add(char letter)
+    {
+        int position = getIndex(letter);
+        /*
+            << or >> operator shifts position of number
+            ex: 1 << 4 makes 10000
+            0000001 -- 0010000
+         */
+        int temp = 1 << position;
+        inventory += temp;
+    }
+
+    public boolean isPresent(char letter)
+    {
+        int position = getIndex(letter);
+        int temp = 1 << position;
+        /* ANDs the two numbers together - checks if any of the values match
+         * 0110000 & 1 << 4
+         * 0010000
+         * 0010000 - AND result
+         *
+         * 0110000 & 1 << 2
+         * 0110100
+         * 0000000 - AND result
+         */
+        int check = inventory & temp;
+        return check > 0;
+    }
+}

tests/inventory/LetterInventoryTest.java

@@ -6,7 +6,7 @@
 import static org.junit.jupiter.api.Assertions.*;
 
 class LetterInventoryTest {
-/*
+
     static LetterInventory washington;
     static LetterInventory empty;
     static LetterInventory atoz;
@@ -125,5 +125,5 @@ void isEmpty() {
         assertFalse(atoz.isEmpty());
         assertFalse(washington.isEmpty());
     }
-*/
+
 }