working

src/main/java/rocks/zipcode/io/quiz4/collections/ComparableTreeSet.java

@@ -14,9 +14,10 @@ public class ComparableTreeSet<_> {
 
 
     public ComparableTreeSet() {
+
     }
 
-    public Integer compareTo(ComparableTreeSet<_> o) {
-        return null;
+    public int compareTo(ComparableTreeSet<_> o) {
+        return 0;
     }
 }

src/main/java/rocks/zipcode/io/quiz4/collections/SimpleStringGroup.java

@@ -1,7 +1,6 @@
 package rocks.zipcode.io.quiz4.collections;
 
 import java.util.ArrayList;
-import java.util.Collection;
 import java.util.List;
 
 /**

src/main/java/rocks/zipcode/io/quiz4/collections/ZipCodeWilmington.java

@@ -2,23 +2,43 @@ package rocks.zipcode.io.quiz4.collections;
 
 import rocks.zipcode.io.quiz4.objectorientation.Student;
 
-import java.util.Map;
+import java.util.*;
 
 /**
  * @author leon on 11/12/2018.
  */
 public class ZipCodeWilmington {
+    List<Map.Entry<Student, Double>>cohort;
+
+    public ZipCodeWilmington() {
+        cohort = new ArrayList<>();
+    }
+
     public void enroll(Student student) {
+        Map.Entry<Student, Double> entry = new AbstractMap.SimpleEntry<>(student, 0.0);
+        cohort.add(entry);
     }
 
     public Boolean isEnrolled(Student student) {
-        return null;
+        for(Map.Entry entry : cohort){
+            if(entry.getKey().equals(student))
+                return true;
+        }
+        return false;
     }
 
     public void lecture(double numberOfHours) {
+        for(Map.Entry entry : cohort) {
+            Student s = (Student) entry.getKey();
+            s.learn(numberOfHours);
+        }
     }
 
     public Map<Student, Double> getStudyMap() {
-        return null;
+        Map<Student, Double> map = new HashMap<>();
+
+        for(Map.Entry entry : cohort)
+            map.put((Student)entry.getKey(), (Double)entry.getValue());
+        return map;
     }
 }

src/main/java/rocks/zipcode/io/quiz4/objectorientation/PalindromeObject.java

@@ -1,21 +1,26 @@
 package rocks.zipcode.io.quiz4.objectorientation;
 
+import rocks.zipcode.io.quiz4.fundamentals.PalindromeEvaluator;
+
 /**
  * @author leon on 18/12/2018.
  */
 public class PalindromeObject {
+    String word;
+
     public PalindromeObject(String input) {
+        word = input;
     }
 
     public String[] getAllPalindromes(){
-        return null;
+        return PalindromeEvaluator.getAllPalindromes(word);
     }
 
     public Boolean isPalindrome(){
-        return null;
+       return PalindromeEvaluator.isPalindrome(word.toLowerCase());
     }
 
     public String reverseString(){
-        return null;
+        return PalindromeEvaluator.reverseString(word);
     }
 }

src/main/java/rocks/zipcode/io/quiz4/objectorientation/StringAssembler.java

@@ -1,17 +1,26 @@
 package rocks.zipcode.io.quiz4.objectorientation;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * @author leon on 11/12/2018.
  */
 public class StringAssembler {
+    char c;
+    String result;
+
     public StringAssembler(Character delimeter) {
+        c = delimeter;
+        result = "";
     }
 
     public StringAssembler append(String str) {
-        return null;
+        result += str + c;
+        return this;
     }
 
     public String assemble() {
-        return null;
+        return this.result.substring(0,result.length()-1);
     }
 }

src/main/java/rocks/zipcode/io/quiz4/objectorientation/StringEvaluatorObject.java

@@ -1,21 +1,26 @@
 package rocks.zipcode.io.quiz4.objectorientation;
 
+import rocks.zipcode.io.quiz4.fundamentals.StringEvaluator;
+
 /**
  * @author leon on 19/12/2018.
  */
 public class StringEvaluatorObject {
+    String word;
+
     public StringEvaluatorObject(String str) {
+        word = str;
     }
 
     public String[] getAllPrefixes() {
-        return null;
+        return StringEvaluator.getAllPrefixes(word);
     }
 
     public String[] getCommonPrefixes(String secondInput) {
-        return null;
+        return StringEvaluator.getCommonPrefixes(word, secondInput);
     }
 
     public String getLargestCommonPrefix(String secondInput) {
-        return null;
+        return StringEvaluator.getLargestCommonPrefix(word, secondInput);
     }
 }

src/main/java/rocks/zipcode/io/quiz4/objectorientation/Student.java

@@ -4,17 +4,24 @@ package rocks.zipcode.io.quiz4.objectorientation;
  * @author leon on 11/12/2018.
  */
 public class Student {
+    double totalStudyTime;
+    int id;
+
     public Student() {
-        this(null);
+        totalStudyTime = 0.0;
+        id = 0;
     }
 
     public Student(Integer id) {
+        this.id = id;
+        this.totalStudyTime = 0.0;
     }
 
     public void learn(Double amountOfHours) {
+        totalStudyTime += amountOfHours;
     }
 
     public Double getTotalStudyTime() {
-        return null;
+        return this.totalStudyTime;
     }
 }