Completed Assignment

src/ArrayPractice.java

@@ -1,18 +1,28 @@
 public class ArrayPractice {
   public static void main(String[] args) {
     // Create an array of Strings of size 4
-
+    String[] newArray = new String[4];
     // Set the value of the array at each index to be a different String
     // It's OK to do this one-by-one
+    newArray[0] = "Hello";
+    newArray[1] = "My";
+    newArray[2] = "Name's";
+    newArray[3] = "Tav";
 
     // Get the value of the array at index 2
-
+    System.out.println(newArray[2]);
     // Get the length of the array
-
+    System.out.println("The length of the array is: " + newArray.length);
     // Iterate over the array using a traditional for loop and print out each item
-
+    for (int i = 0; i < newArray.length; i++) {
+      System.out.println(newArray[i]);
+    }
     // Iterate over the array using a for-each loop and print out each item
-
+    // Breaking to show for each
+    System.out.println();
+    for (String words:newArray) {
+      System.out.println(words);
+    }
     /*
      * Reminder!
      * 

src/ListPractice.java

@@ -1,28 +1,42 @@
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
 public class ListPractice {
 
 
   public static void main(String[] args) {
     // Create an empty ArrayList of Strings and assign it to a variable of type List
-
+    List<String> stringList = new ArrayList<>();
     // Add 3 elements to the list (OK to do one-by-one)
-
+    stringList.add("Pulp");
+    stringList.add("Round");
+    stringList.add("Strange");
     // Print the element at index 1
+    System.out.println(stringList.get(1));
 
     // Replace the element at index 1 with a new value
     // (Do not insert a new value. The length of the list should not change)
-
+    stringList.set(1, "Juice");
+    System.out.println(stringList.get(1));
     // Insert a new element at index 0 (the length of the list will change)
-
+    stringList.add(0, "Oh");
+    System.out.println(stringList.get(0));
     // Check whether the list contains a certain string
-
+    System.out.println(stringList.contains("Juice"));
     // Iterate over the list using a traditional for-loop.
     // Print each index and value on a separate line
-
+    for (int i = 0; i < stringList.size(); i++) {
+        System.out.println("Index: " + i + ", Value: " +stringList.get(i));
+    }
     // Sort the list using the Collections library
-
+    Collections.sort(stringList);
+    System.out.println(stringList);
     // Iterate over the list using a for-each loop
     // Print each value on a second line
-
+    for (String word : stringList) {
+        System.out.println(word);
+    }
     /*
      * Usage tip!
      * 

src/MapPractice.java

@@ -1,29 +1,44 @@
+import java.util.HashMap;
+import java.util.Map;
 
 
 public class MapPractice {
   public static void main(String[] args) {
     // Create a HashMap with String keys and Integer values and
     // assign it to a variable of type Map
-
+    Map<String, Integer> newMap = new HashMap<>();
     // Put 3 different key/value pairs in the Map
     // (it's OK to do this one-by-one)
+    newMap.put("For", 1);
+    newMap.put("Gas", 2);
+    newMap.put("Port", 3);
 
-    // Get the value associated with a given key in the Map
 
+    // Get the value associated with a given key in the Map
+    System.out.println(newMap.get("Port"));
     // Find the size (number of key/value pairs) of the Map
-
-    // Replace the value associated with a given key (the size of the Map shoukld not change)
-
+    System.out.println(newMap.size());
+    // Replace the value associated with a given key (the size of the Map should not change)
+    newMap.replace("For", 9);
     // Check whether the Map contains a given key
-
+    System.out.println(newMap.containsKey("Port"));
     // Check whether the Map contains a given value
-
+    System.out.println(newMap.containsValue(4));
     // Iterate over the keys of the Map, printing each key
-
+    System.out.println("Keys:");
+    for (String keys : newMap.keySet()) {
+      System.out.println(keys);
+    }
     // Iterate over the values of the map, printing each value
-
+    System.out.println("Values:");
+    for (Integer values : newMap.values()) {
+      System.out.println(values);
+    }
     // Iterate over the entries in the map, printing each key and value
-
+    System.out.println("Both Keys and Values");
+    for (Map.Entry<String, Integer> set : newMap.entrySet()) {
+        System.out.println("Keys: " + set.getKey() + ", Values: " + set.getValue());
+    }
     /*
      * Usage tip!
      * 

src/NumberPractice.java

@@ -1,18 +1,22 @@
 public class NumberPractice {
   public static void main(String args[]) {
     // Create a float with a negative value and assign it to a variable
-
+    float floatingNum = -2l;
     // Create an int with a positive value and assign it to a variable
-
+    int regNum = 22;
     // Use the modulo % operator to find the remainder when the int is divided by 3
-
+    System.out.println(regNum % 3);
     // Use the modulo % operator to determine whether the number is even
     // (A number is even if it has a remainder of zero when divided by 2)
     // Use an if-else to print "Even" if the number is even and "Odd"
     // if the number is odd.
-
+    if (regNum % 2 == 0) {
+      System.out.println("Even");
+    } else {
+      System.out.println("Odd");
+    }
     // Divide the number by another number using integer division
-
+    System.out.println(regNum / 6);
     /*
      * Reminder!
      * 

src/Person.java

@@ -6,14 +6,20 @@
 public class Person {
   // Declare a public String instance variable for the name of the person
   // Declare a private int instance variable for the age of the person
-
+  public String name;
+  private int age;
 
   // Create a constructor that takes the name and age of the person
   // and assigns it to the instance variables
-
+  public Person(String name, int age) {
+    this.name = name;
+    this.age = age;
+  }
 
   // Create a toString method that gives the name and age of the person
-
+  public String toString() {
+    return "This is " + name + ", they are " + age;
+  }
 
   // Implement the below public instance method "birthYear"
   // There should NOT be any print statement in this method.
@@ -28,26 +34,29 @@ public class Person {
    * @return The year the person was born
    */
   // (create the instance method here)
+  public int birthYear(int currentYear) {
+    return currentYear - age;
+  }
 
 
   public static void main(String[] args) {
     // Create an instance of Person
-
+    Person dude = new Person("Dante", 20);
     // Create another instance of Person with a different name and age and
     // assign it to a different variable
-
+    Person dudeTwo = new Person("Vergil", 21);
     // Print the first person
-
+    System.out.println(dude);
     // Print the second person
-
+    System.out.println(dudeTwo);
     // Get the name of the first person and store it in a local variable
-
+    String fName = dude.name;
     // Using the birthYear method, get the birth year of the first person
     // and store it in a local variable. Input the actual current year (e.g. 2025)
     // as the argument.
-
+    int fBirth = dude.birthYear(2025);
     // In a separate statement, print the local variable holding the birth year.
-
+    System.out.println(fBirth);
     /**
      * Terminology!
      * 

src/SetPractice.java

@@ -1,18 +1,30 @@
+import java.util.HashSet;
+import java.util.Set;
+
 public class SetPractice {
   public static void main(String[] args) {
     // Create a HashSet of Strings and assign it to a variable of type Set
+    Set<String> newSet = new HashSet<>();
 
     // Add 3 elements to the set
     // (It's OK to do it one-by-one)
-
+    newSet.add("Hello");
+    newSet.add("World");
+    newSet.add("Smile?");
     // Check whether the Set contains a given String
-
+    if (newSet.contains("Smile?")) {
+      System.out.println("True");
+    } else {
+      System.out.println("False");
+    }
     // Remove an element from the Set
-
+    newSet.remove("Hello");
     // Get the size of the Set
-
+    System.out.println(newSet.size());
     // Iterate over the elements of the Set, printing each one on a separate line
-
+    for (String word : newSet) {
+      System.out.println(word);
+    }
     /*
      * Warning!
      * 

src/StringPractice.java

@@ -1,26 +1,46 @@
+import java.util.ArrayList;
+import java.util.List;
+
 public class StringPractice {
   public static void main(String[] args) {
     // Create a string with at least 5 characters and assign it to a variable
-
+    String word = "Fives";
     // Find the length of the string
-
+    System.out.println(word.length());
     // Concatenate (add) two strings together and reassign the result
-
+    word += " high?";
+    System.out.println(word);
     // Find the value of the character at index 3
-
+    System.out.println(word.charAt(3));
     // Check whether the string contains a given substring (i.e. does the string have "abc" in it?)
-
+    if (word.contains("high")) {
+      System.out.println("True");
+    } else {
+      System.out.println("False");
+    }
     // Iterate over the characters of the string, printing each one on a separate line
-
+    for (Character letter : word.toCharArray()) {
+        System.out.println(letter);
+    }
     // Create an ArrayList of Strings and assign it to a variable
-
+    List<String> newList = new ArrayList<>();
     // Add multiple strings to the List (OK to do one-by-one)
+    newList.add("Apple");
+    newList.add("bottom");
+    newList.add("jeans");
+    newList.add("boots");
+    newList.add("with the?");
 
     // Join all of the strings in the list together into a single string separated by commas
     // Use a built-in method to achieve this instead of using a loop
-
+    String lyric = String.join(", ", newList);
+    System.out.println(lyric);
     // Check whether two strings are equal
-
+    if (lyric.equals(word)) {
+      System.out.println("True");
+    } else {
+      System.out.println("False");
+    }
     /*
      * Reminder!
      * 

toRefresh.md

@@ -2,4 +2,5 @@
 
 As you work through this exercise, write down anything that you needed to look up or struggled to remember here. It can be just a word or two (e.g. "joining strings"). You can use this as a guide of what to make extra sure you're refreshed on before exams and interviews.
 
-- 
+- Refresh on methods used in general
+- Refresh on java constructors and fields