Section 4.72 Unit 4B Projects

90 minutes

These projects were created by Leigh Anne Fitz and Lisa Ferran to provide engaging, standards-aligned learning experiences for AP Computer Science A students. The autograding tests were designed by Kate McDonnell.

Now that you’ve learned to work with arrays, it’s time to explore ArrayLists—a flexible data structure that can grow and shrink as your program runs. In these projects, you’ll learn how to create and manipulate ArrayList objects, access and update elements, add and remove items, and develop algorithms that process dynamic collections of data.

Each project is designed to reinforce these concepts through authentic programming tasks. As you complete them, focus on selecting the appropriate ArrayList methods, using loops to process collections efficiently, and carefully managing element positions as data is added or removed. Mastering ArrayLists will help you build programs that are more adaptable and better suited for managing real-world data.

Subsection 4.72.1 Unit 4B Project 1 - Remove Duplicates

Activity 4.72.1.

Create a program that will remove duplicate values from an ArrayList. In the main method, create an ArrayList of Integers. Fill the ArrayList with 20 random Integers in the range 1 to 10 using a for loop. Print your ArrayList with all values on one line with a space between them using a for loop. Write a static method called removeDuplicates that will receive your ArrayList as a parameter and return the ArrayList with all duplicate values removed. The method should also print out the values that it is removing as they are being removed. You are to do this with nested for loops (use i and j as your loop variables). Remember to think about what happens with your index values when you remove an element. Back in main, print out the ArrayList returned by the method.

Example:

Original list:  3 5 1 2 3 9 10 10 7 1 3 4 8 10 7 5 2 6 4 2
Removed:  3
Removed:  3
Removed:  5
Removed:  1
Removed:  2
Removed:  2
Removed:  10
Removed:  10
Removed:  7
Removed:  4
List without Duplicates:  3 5 1 2 9 10 7 4 8 6

import java.util.ArrayList;

public class Main {
  public static void main(String[] args) {

}

// This code will not compile until you create your removeDuplicates method header
  
}
====
    import static org.junit.Assert.*;
    import org.junit.*;
    import java.io.*;
    import java.util.Arrays;
    import java.util.ArrayList;

public class RunestoneTests extends CodeTestHelper
    {
        public RunestoneTests() {
            super("Main");
        }
       
       
        private static String input1 = "";
        private static String input2 = "";
        private static String input3 = "";

@Test
        public void test01(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
            String expected = "ArrayList<Integer>";
            String actual = "";

for (String line : lines){
                if (line.contains(expected)) {
                    actual += line + "\n";
                }
            }

boolean passed = stringMatch(actual, "new " + expected + "()")
    || stringMatch(actual, "new ArrayList<>()");
            expected = expected + " * = new " + expected + "()";
            getResults(replaceTags(expected),replaceTags(actual),"ArrayList of Integers created properly",passed);
            assertTrue(passed);
        }

@Test
            public void test02(){
                String code = getCode();
                code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
                String expected = "Math.random()";
                String actual = "";

for (String line : lines){
                    if (line.contains(expected)) {
                        actual += line + "\n";
                    }
                }

boolean cast = stringMatch(actual, "(int)");
                boolean shift = stringMatch(actual,"+1");
                boolean range = stringMatch(actual,"*10");

boolean passed = cast && shift && range;

String expect = "Cast: true\nRange: true\nShift: true";
                actual += "Cast: " + cast + "\nRange: " + range + "\nShift: " + shift;
                   
               
                getResults(expect,actual,"Math.random() used to create an integer in the range [1, 10]",passed);
                assertTrue(passed);
            }

@Test
            public void test03(){
                String code = getCode();
                code = getMethodCode(code, "main(String[] args)");
                code = getMethodCode(code, "for");

String[] lines = code.split("\n");
                String expected = "for";
                String actual = "";

boolean loop = false;

for (String line : lines){
                    if (line.contains(expected) && line.contains("20")) {
                        actual += line + "\n";
                        loop = true;
                    } else if (loop && line.contains(".add(")) {
                        actual += line + "\n";
                        break;
                    }
                }

boolean passed = stringMatch(actual, "for (int") && actual.contains("++") && actual.contains(".add(");
                boolean pass2 = stringMatch(actual, "= 0") && stringMatch(actual, "< 20");
                boolean pass3 = stringMatch(actual, "= 1") && stringMatch(actual, "<= 20");
                boolean pass4 = pass2 || pass3;
                passed = passed && pass4;
               
                expected = "for(int i = 0; i < 20; i++)";
                getResults(expected,actual,"20 random integers are added to the ArrayList using a for loop",passed);
                assertTrue(passed);
            }

@Test
            public void test04(){
                String code = getCode();

String[] lines = code.split("\n");
                String expected = "removeDuplicates";
                String actual = "";

for (String line : lines){
                    if (line.contains(expected) && line.contains("public")) {
                        actual += line + "\n";
                    }
                }

expected =  "public static ArrayList<Integer> removeDuplicates(ArrayList<Integer>";
                boolean passed = stringMatch(actual,expected);
               
                getResults(replaceTags(expected + " *)"),replaceTags(actual),"Header for removeDuplicates method is correct",passed);
                assertTrue(passed);
            }

@Test
            public void test05(){
                String desc = "Nested for loops used to traverse arrays";
               
               
                try {
                    String code = getCode();
                   
                    code = getMethodCode(code, "public static ArrayList<Integer>");
                    //System.out.println(code);
   
                    String[] lines = code.split("\n");
                    String expected = "for";
                    String actual = "";
   
                    for (String line : lines){
                        if (line.contains(expected)) {
                            actual += line.trim() + "\n";
                        }
                    }
   
                    int fors = countOccurences(actual, "for");
                    int size = countOccurences(actual, ".size()");
   
   
   
                    String forwardStr  = "for\\(int([a-zA-Z0-9_]+)=(0|[a-zA-Z0-9_]+\\+1);\\1<[a-zA-Z0-9_]+.size\\(\\)[-1]*;\\1\\+\\+\\)\\{*";
                    String backwardStr = "for\\(int([a-zA-Z0-9_]+)=[a-zA-Z0-9_\\.\\(\\)]*-1;\\1>=*[a-zA-Z0-9]*;\\1--\\)\\{*";
   
                    String[] loops = actual.split("\n");
                    int numLoops = loops.length;
   
                   
                    int forward = 0, backward = 0;
   
   
   
   
                    if (numLoops == 2) {
                        for (String line : loops) {
                            //System.out.println(line);
                            if(line.replaceAll(" ", "").matches(forwardStr)) {
                               //System.out.println(line + " --> forward");
                                forward++;
                            }
   
                            if(line.replaceAll(" ", "").matches(backwardStr)) {
                                //System.out.println(line + " --> backward");
                                backward++;
                            }
   
                        }
   
                    }
                    /**/                
   
                    expected =  "for(int i = 0; i < d.size(); i++)\n" +
                         "for(int j = i + 1; j < d.size(); j++)\n\n";
                    boolean passed = forward + backward == 2;
   
                    getResults(expected,actual,desc,passed);
                    assertTrue(passed);
                } catch (Exception e) {
                    String expected =  "for(int i = 0; i < d.size(); i++)\n" +
                         "for(int j = i + 1; j < d.size(); j++)\n\n";
                    String actual = "Test caused an exception";

boolean passed = getResults(expected,actual,desc);
                    assertTrue(false);
                }
               
            }

@Test
            public void test06(){
                String desc = "if statement used for comparison of two data elements";
                try {
                    String code = getCode();
                    code = getMethodCode(code, "public static ArrayList<Integer>");
   
                    String[] lines = code.split("\n");
                    String expected = "if";
                    String actual = "";
   
                    for (String line : lines){
                        if (line.contains(expected)) {
                            actual += line + "\n";
                        }
                    }
   
boolean passed = countOccurences(actual, ".get(") == 2
    && (actual.contains("==") || actual.contains(".equals("));
                    expected = "if (*.get(*) == *.get(*))";
                    getResults(expected,actual,desc,passed);
                    assertTrue(passed);

} catch (Exception e) {
                    String expected =  "if (*.get(*) == *.get(*))";
                    String actual = "Test caused an exception";

boolean passed = getResults(expected,actual,desc);
                    assertTrue(false);
                }
            }

@Test
            public void test07(){
                String desc = "System.out.print used at least twice to print elements from list in main method";
                try {
                    String code = getCode();
                    code = getMethodCode(code, "main(String[] args");
   
                    String[] lines = code.split("\n");
                    String expected = "System.out.print(";
                    String actual = "";
   
                    for (String line : lines){
                        if (line.contains(expected) && line.contains(".get")) {
                            actual += line + "\n";
                        }
                    }
   
                    boolean passed = actual.split("\n").length >= 2;
                    expected = "System.out.print(*.get(*));\nSystem.out.print(*.get(*));";
                    getResults(expected,actual, desc, passed);
                    assertTrue(passed);

} catch (Exception e) {
                    String expected = "System.out.print(*.get(*));\nSystem.out.print(*.get(*));";
                    String actual = "Test caused an exception";

boolean passed = getResults(expected,actual,desc);
                    assertTrue(false);
                }
            }

@Test
            public void test08(){
                String desc = "System.out.println used at least once to print elements as they are removed in removeDuplicates method";
                try {
                    String code = getCode();
                    code = getMethodCode(code, "public static ArrayList<Integer>");
   
                    String[] lines = code.split("\n");
                    String expected = "System.out.print";
                    String actual = "";
   
                    for (String line : lines){
                        if (line.contains(expected)) {
                            actual += line + "\n";
                        }
                    }
   
                    boolean passed = actual.contains(".get(") || actual.contains(".remove(");
                    expected = "System.out.println(*.get(*)); // or\nSystem.out.println(*.remove(*));";
                    getResults(expected,actual,desc,passed);
                    assertTrue(passed);

} catch (Exception e) {
                    String expected = "System.out.println(*.get(*)); // or\nSystem.out.println(*.remove(*));";
                    String actual = "Test caused an exception";

boolean passed = getResults(expected,actual,desc);
                    assertTrue(false);
                }
            }

@Test
        public void test09() {
            ArrayList<Integer> list1 = new ArrayList <Integer> (Arrays.asList(10, 1, 4, 4, 2, 1, 5, 5, 6, 7, 7, 5, 10, 5, 1, 4, 1, 10, 6, 6));
            String list = list1.toString();
            ArrayList<Integer> result = Main.removeDuplicates(list1);
            ArrayList<Integer> expect = new ArrayList <Integer> (Arrays.asList(10, 1, 4, 2, 5, 6, 7));

boolean passed = result.equals(expect);
            getResults(expect.toString(), result.toString(), "Testing with values " + list, passed);
            assertTrue(passed);
        }

@Test
            public void test10() {
                ArrayList<Integer> list1 = new ArrayList <Integer> (Arrays.asList(3, 3, 7, 8, 3, 7, 6, 4, 9, 9, 9, 1, 8, 4, 9, 3, 5, 1, 1, 10));
                String list = list1.toString();
                ArrayList<Integer> result = Main.removeDuplicates(list1);
                ArrayList<Integer> expect = new ArrayList <Integer> (Arrays.asList(3, 7, 8, 6, 4, 9, 1, 5, 10));

boolean passed = result.equals(expect);

getResults(expect.toString(), result.toString(), "Testing with values " + list, passed);
                assertTrue(passed);
            }

private String getMethodCode(String code, String name) {
            String searchStr = code;
            int start = searchStr.indexOf(name);
            searchStr = searchStr.substring(start);

int level = 0;

for (int i = 0; i < searchStr.length(); i++) {
                if (searchStr.substring(i,i+1).equals("{")) {
                    level++;
                } else if (searchStr.substring(i,i+1).equals("}")) {
                    level--;

if (level == 0) {
                        //System.out.println(searchStr.substring(0, i+1).trim());
                        return searchStr.substring(0, i+1).trim();
                    }
                }
            }

return searchStr.trim();
        }

private boolean stringMatch(String str1, String str2) {
            str1 = str1.replaceAll(" ", "");
            str2 = str2.replaceAll(" ", "");

return str1.contains(str2);
        }

private String replaceTags(String str) {
            return str.replaceAll(">","&gt;").replaceAll("<","&lt;");
        }
    }

Subsection 4.72.2 Unit 4B Project 2 - ArrayList Operations

Activity 4.72.2.

Create a program that utilizes common ArrayList algorithms. In main, create an ArrayList of Integers. Use a for loop to fill the ArrayList with 50 random Integers in the range 0 to 100. Create static methods to return the following values:

Table 4.72.1. ArrayList Operations - Static Methods

Statement	Return Value (blank if no value)	Explanation
`// list1 = [14, 42, 73, 89, 31]`		Assume list1 has been created properly and that the values have been added
`sum(list1)`	249	Returns the sum of all the numbers in list1
`average(list1)`	49.8	Returns the average of all the numbers in list1
`maximum(list1)`	89	Returns the maximum of all the numbers in list1
`minimum(list1)`	14	Returns the minimum of all the numbers in list1
`// list2 = [18, 45, 81, 62, 27, 94]`		Assume list2 has been created property and that the values have been added
`sum(list2)`	327	Returns the sum of all the numbers in list2
`average(list2)`	46.6	Returns the average of all the numbers in list2
`maximum(list2)`	81	Returns the maximum of all the numbers in list2
`minimum(list2)`	18	Returns the minimum of all the numbers in list2

Call each of the methods in the main method and print out the results. All methods should be static. Be sure to label your output with the corresponding information for each number.

import java.util.ArrayList;

public class Main {
    public static void main(String[] args) {

}

// This code will not compile until you create your method headers 
    // (and return something in each method)

}
====
import static org.junit.Assert.*;
import org.junit.*;
import java.io.*;
import java.util.Arrays;
import java.util.ArrayList;

public class RunestoneTests extends CodeTestHelper
{
    public RunestoneTests() {
        //super("Main", input1.replaceAll(" ", "\n")); // For Book
    }

private static String input1 = "";
    private static String input2 = "";
    private static String input3 = "";

@Test
    public void test01(){
        String code = getCode();
        code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
        String expected = "ArrayList<Integer>";
        String actual = "";

for (String line : lines){
            if (line.contains(expected)) {
                actual += line + "\n";
            }
        }

boolean passed = stringMatch(actual, "new " + expected + "()")
    || stringMatch(actual, "new ArrayList<>()");
        expected = expected + " * = new " + expected + "()";
        getResults(replaceTags(expected),replaceTags(actual),"ArrayList of Integers created properly",passed);
        assertTrue(passed);
    }

@Test
        public void test02(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
            String expected = "Math.random()";
            String actual = "";

for (String line : lines){
                if (line.contains(expected)) {
                    actual += line + "\n";
                }
            }

boolean cast = stringMatch(actual, "(int)");
            boolean range = stringMatch(actual,"*101");

boolean passed = cast && range;

String expect = "Cast: true\nRange: true";
            actual += "Cast: " + cast + "\nRange: " + range;
                
            
            getResults(expect,actual,"Math.random() used to create an integer in the range [0, 100]",passed);
            assertTrue(passed);
        }

@Test
        public void test03(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args)");
            code = getMethodCode(code, "for");

String[] lines = code.split("\n");
            String expected = "for";
            String actual = "";

boolean loop = false;

for (String line : lines){
                if (line.contains(expected) && line.contains("50")) {
                    actual += line + "\n";
                    loop = true;
                } else if (loop && line.contains(".add(")) {
                    actual += line + "\n";
                    break;
                }
            }

boolean passed = stringMatch(actual, "for (int") && actual.contains("++") && actual.contains(".add(");
            boolean pass2 = stringMatch(actual, "= 0") && stringMatch(actual, "< 50");
            boolean pass3 = stringMatch(actual, "= 1") && stringMatch(actual, "<= 50");
            boolean pass4 = pass2 || pass3;
            passed = passed && pass4;
            
            expected = "for(int i = 0; i < 50; i++)\n\t*.add(*)";
            getResults(expected,actual,"50 random integers are added to the ArrayList using a for loop",passed);
            assertTrue(passed);
        }

@Test
        public void test04(){
            String code = getCode();

String[] lines = code.split("\n");
            String expect = "sum";
            String actual = "";

for (String line : lines){
                if (line.contains("public static ") && !line.contains("main")) {
                    actual += line + "\n";
                    //System.out.println(line);
                }
            }

int num = actual.split("\n").length;
            int ints = countOccurences(actual, "static int");
            int doubles = countOccurences(actual, "double");
            int params = countOccurences(actual, "(ArrayList<Integer>");
            
            String expected =  "public static: 4\nint Return type: 3\n";
            expected += "Return type double: 1\nParameters: 4";

String result =  "public static: "+ num + "\nint Return type: " + ints + "\n";
                result += "Return type double: "+ doubles + "\nParameters: " + params;
            
            boolean passed = result.contains(expected);

getResults(expected,result,"Method headers",passed);
            assertTrue(passed);
        }

@Test
    public void test05() {
        String output = getMethodOutput("main");

boolean sum = stringMatch(output, "sum");
        boolean avg = stringMatch(output, "average");
        boolean min = stringMatch(output, "min");
        boolean max = stringMatch(output, "max");

boolean passed = sum && avg && min && max;

String expected = "sum\naverage\nmaximum\nminimum";

getResults(expected,output,"Output includes labels",passed);
        assertTrue(passed);
    }

@Test
        public void test06() {
            String output1 = getMethodOutput("main");
            String output2 = getMethodOutput("main");

boolean passed = !output1.equals(output2);

String expected = "Random results: true\nPrint double: 1\nPrint ints: 3";

String output = output1.replaceAll("[^\\.^0-9^\\n]", "");
            String actual = "Random results: " + passed + "\n";
            int doubles = countOccurences(output, ".");
            int ints = output.split("\n").length - doubles;
            actual += "Print double: " + doubles + "\n";
            actual += "Print ints: " + ints;

passed = expected.equals(actual);
            
            getResults(expected,actual,"Output includes results from random values",passed);
            assertTrue(passed);
        }

@Test
        public void test07(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args");

String[] lines = code.split("\n");
            String actual = "";
            boolean sum = false, avg = false, max = false, min = false;

for (String line : lines){
                if (line.contains("sum(")) {
                    actual += line + "\n"; sum = true;
                } else if (line.contains("average(")) {
                    actual += line + "\n"; avg = true;
                } else if (line.contains("maximum(")) {
                    actual += line + "\n"; max = true;
                } else if (line.contains("minimum(")) {
                    actual += line + "\n"; min = true;
                }
            }

String expected = "sum(*)\naverage(*)\nmaximum(*)\nminimum(*)";
            
            boolean passed = sum && avg && max && min;

getResults(expected,actual,"Calls all four methods in main",passed);
            assertTrue(passed);
        }
    
    @Test
        public void test08(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args");

String[] lines = code.split("\n");
            String expected = "System.out.println(";
            String actual = "";

for (String line : lines){
                if (line.contains(expected)) {
                    actual += line + "\n";
                }
            }

int times = actual.split("\n").length;
            boolean passed = times >= 4;
            
            getResults("4+",""+times,"System.out.println used at least 4 times",passed);
            assertTrue(passed);
        }

@Test
    public void test09() {
        ArrayList<Integer> list1 = new ArrayList <Integer> (Arrays.asList(89, 97, 27, 27, 87, 16, 69, 19, 53, 71, 87, 23, 3, 83, 36, 30, 52, 50, 72, 62, 21, 29, 31, 2, 67, 27, 61, 76, 30, 19, 48, 84, 98, 54, 92, 31, 75, 89, 21, 94, 91, 12, 28, 69, 42, 67, 2, 100, 21, 12));
        String list = list1.toString();

int sum = Main.sum(list1);
        double avg = Main.average(list1);
        int min = Main.minimum(list1);
        int max = Main.maximum(list1);

String expected = "Sum: 2546\nAverage: 50.92\nMaximum: 100\nMinimum: 2";
        String result = "Sum: " + sum + "\nAverage: ";
        result += String.format("%.2f", avg);
            result += "\nMaximum: " + max + "\nMinimum: " + min;

boolean passed = result.equals(expected);
        getResults(expected, result, "Testing with values " + list, passed);
        assertTrue(passed);
    }

@Test
        public void test10() {
            ArrayList<Integer> list1 = new ArrayList <Integer> (Arrays.asList(12, 87, 46, 9, 65, 49, 19, 24, 91, 60, 7, 46, 16, 18, 72, 47, 94, 80, 77, 97, 3, 34, 32, 84, 99, 72, 64, 56, 50, 27, 77, 74, 59, 92, 2, 71, 41, 42, 55, 14, 0, 82, 52, 96, 40, 2, 40, 96, 95, 74));
            String list = list1.toString();

int sum = Main.sum(list1);
            double avg = Main.average(list1);
            int min = Main.minimum(list1);
            int max = Main.maximum(list1);

String expected = "Sum: 2641\nAverage: 52.82\nMaximum: 99\nMinimum: 0";
            String result = "Sum: " + sum + "\nAverage: ";
            result += String.format("%.2f", avg);
                result += "\nMaximum: " + max + "\nMinimum: " + min;

boolean passed = result.equals(expected);
            getResults(expected, result, "Testing with values " + list, passed);
            assertTrue(passed);
        }

private String getMethodCode(String code, String name) {
        String searchStr = code;
        int start = searchStr.indexOf(name);
        searchStr = searchStr.substring(start);

int level = 0;

for (int i = 0; i < searchStr.length(); i++) {
            if (searchStr.substring(i,i+1).equals("{")) {
                level++;
            } else if (searchStr.substring(i,i+1).equals("}")) {
                level--;

if (level == 0) {
                    //System.out.println(searchStr.substring(0, i+1).trim());
                    return searchStr.substring(0, i+1).trim();
                }
            }
        }

return searchStr.trim();
    }

private boolean stringMatch(String str1, String str2) {
        str1 = str1.replaceAll(" ", "");
        str2 = str2.replaceAll(" ", "");

return str1.contains(str2);
    }

private String replaceTags(String str) {
        return str.replaceAll(">","&gt;").replaceAll("<","&lt;");
    }
}

Subsection 4.72.3 Unit 4B Project 3 - List of Students

Activity 4.72.3.

Create a program that uses ArrayLists with a Student class. Leave Main alone for now and create a class called Student (do not make it public). Use the following specifications for the Student class:

A student should have a name and a grade level
Create a single one parameter constructor where the name is passed in as a parameter and the grade level is created randomly (9 - 12)
Create getters and setters for each instance variable and create a toString method

Back in Main, create an ArrayList of Students. Do the following:

Use a for loop to fill the ArrayList with 10 Students
You will need to prompt the user to add the name for each student
Create four more ArrayLists, one for each grade level, to hold Student objects
Fill each of these, using a for-each loop, with students from your original ArrayList with the corresponding grade level (all 9th grade students should be added to your ArrayList for 9th graders, all 10th grade students should be added to your ArrayList for 10th graders, and so on)
Print the number of students in each grade level using the size of the four grade level ArrayLists using four separate println statements
Be sure to label which grade level each number represents

import java.util.ArrayList;
import java.util.Scanner;

public class Main {
  public static void main(String[] args) {

}
}

// create your Student class here - do not put the word public in front of the class name
====
import static org.junit.Assert.*;
import org.junit.*;
import java.io.*;
import java.util.Arrays;
import java.util.ArrayList;

public class RunestoneTests extends CodeTestHelper
{
    public RunestoneTests() {
        //super("Main", input1.replaceAll(" ", "\n")); // For Book
    }

private static String input1 = "Bob Jane Sam Sue Jon Alice Peter Michael Joey Kate ";
    private static String input2 = "";
    private static String input3 = "";

@Test
    public void test01(){
        String code = getCode();
        code = getMethodCode(code, "class Student");

String[] lines = code.split("\n");
        String expected = "private";
        String actual = "";

for (String line : lines){
            if (line.contains(expected)) {
                actual += line + "\n";
            }
        }

boolean passed = actual.contains("int") && actual.contains("String");
        expected = "private String *;\nprivate int *;";
        getResults(expected,actual,"Instance variables created for Student class",passed);
        assertTrue(passed);
    }

@Test
        public void test02(){
            String code = getCode();
            code = getMethodCode(code, "class Student");

String[] lines = code.split("\n");
            String expected = "public Student";
            String actual = "";

for (String line : lines){
                if (line.contains(expected) && line.contains("String")) {
                    actual += line + "\n";
                }
            }

boolean passed = actual.split("\n").length == 1;
            expected = "public Student(String *)";
            getResults(expected,actual,"Instance variables created for Student class",passed);
            assertTrue(passed);
        }

@Test
        public void test03(){
            String code = getCode();
            code = getMethodCode(code, "public Student");

String[] lines = code.split("\n");
            String expected = "Math.random()";
            String actual = "";

for (String line : lines){
                if (line.contains(expected)) {
                    actual += line + "\n";
                }
            }

boolean cast = stringMatch(actual, "(int)");
            boolean range = stringMatch(actual,"*4");
            boolean shift = stringMatch(actual, "+9");

boolean passed = cast && range && shift;

String expect = "Cast: true\nRange: true\nShift: true";
            actual += "Cast: " + cast + "\nRange: " + range + "\nShift: " + shift;
               
           
            getResults(expect,actual,"Math.random() used to create an integer in the range [9, 12]",passed);
            assertTrue(passed);
        }
   
    @Test
        public void test04(){
            String code = getCode();
            code = getMethodCode(code, "class Student");

String[] lines = code.split("\n");
            String expected = "";
            String getters = "";
            String setters = "";
            boolean name = false, grade = false;

for (String line : lines){
                if (line.contains("get") && line.contains("public") && line.contains("()")) {
                    getters += line.trim() + "\n";
                } else if (line.contains("set") && line.contains("public void")) {
                    setters += line.trim() + "\n";
                    if (line.contains("Name") && line.contains("String")) name = true;
                    if (line.contains("GradeLevel") && line.contains("int")) grade = true;
                }
            }

boolean passed = getters.split("\n").length == 2 && setters.split("\n").length == 2 && name && grade;
           
            expected = "public String getName()\npublic int getGradeLevel()\npublic void setName(String *)\npublic void setGradeLevel(int *)";
            String actual = getters + setters;
            getResults(expected,actual,"Accessors and Mutators created for Student class",passed);
            assertTrue(passed);
        }

@Test
        public void test05(){
            String code = getCode();
            code = getMethodCode(code, "class Student");

String[] lines = code.split("\n");
            String expected = "toString()";
            String actual = "";

for (String line : lines){
                if (stringMatch(line,expected)) {
                    actual += line + "\n";
                }
            }
           
            boolean passed = actual.contains("public String");

getResults("public String toString()",actual,"toString method header is correct",passed);
            assertTrue(passed);
        }
   
    @Test
        public void test06(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
            String expected = "ArrayList<Student>";
            String actual = "";

for (String line : lines){
                if (stringMatch(line,expected)) {
                    actual += line + "\n";
                }
            }

int num = actual.split("\n").length;
            boolean passed = num >= 5;
           
            getResults("5","" + num,"ArrayList of Students created properly",passed);
            assertTrue(passed);
        }

@Test
        public void test07(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
            String expected = "for (";
            String actual = "";
            boolean regFor = false, enhFor = false;

for (String line : lines){
                if (stringMatch(line,expected)) {
                    actual += line.trim() + "\n";
                    regFor = regFor || (line.contains("int") && (line.contains(".size()") || line.contains("10")));
                    enhFor = enhFor || (line.contains("Student") && line.contains(":"));
                }
            }

boolean passed = regFor && enhFor;
            expected = "for(int i = 0; i < 10; i++)\nfor(Student * : *)";
            getResults(expected,actual,"At least 1 for loop and 1 enhanced for loop",passed);
            assertTrue(passed);
        }

@Test
        public void test08(){
            String code = getCode();
            code = getMethodCode(code, "main(String[] args)");

String[] lines = code.split("\n");
            String expected = "if (";
            String actual = "";

for (String line : lines){
                if (stringMatch(line,expected)) {
                    actual += line.trim() + "\n";
                } else if (stringMatch(line,".getGradeLevel()")) {
                        actual += line.trim() + "\n";
                    }
            }

boolean num = actual.split("\n").length >= 4;
            boolean equals = countOccurences(actual, "==") == 4;
            boolean gets = countOccurences(actual, ".getGradeLevel()") >= 1;
            boolean grades = actual.contains("9") && actual.contains("10") && actual.contains("11") && actual.contains("12");
            boolean passed = num && equals && gets && grades;
            expected = "if x 4\n== x 4\ngrades: 9-12\n.getGradeLevel()";
            getResults(expected,actual,"if statements used to determine which grade level ArrayList to add students to",passed);
            assertTrue(passed);
        }

@Test
    public void test09() {
        String className = "StudentsTest1";
        String code = getCode();

String actual = "";
        String expected = "Number of ninth graders: 4\n" +
            "Number of tenth graders: 2\n" +
            "Number of eleventh graders: 2\n" +
            "Number of twelfth graders: 2";

if(code.contains("new ArrayList")) {

code = code.replace("Main", className).replace("public class", "class");
        int iFor = code.indexOf("for(int");

if (iFor == -1) iFor = code.indexOf("for (int");
        int iEnd = code.indexOf("}", iFor) + 1;

int inAL = code.indexOf("<Student>");
        int inEq = code.indexOf("=", inAL);
        String name = code.substring(inAL, inEq).split(" ")[1].trim();
       
        String newCode = "\n\ns.get(0).setGradeLevel(12);\n  s.get(1).setGradeLevel(9);\n  s.get(2).setGradeLevel(11);\n  s.get(3).setGradeLevel(9);\n  s.get(4).setGradeLevel(9);\n  s.get(5).setGradeLevel(10);\n  s.get(6).setGradeLevel(10);\n  s.get(7).setGradeLevel(9);\n  s.get(8).setGradeLevel(11);\n  s.get(9).setGradeLevel(12);";
        newCode = newCode.replaceAll("s.get", name + ".get");

code = code.substring(0, iEnd) + newCode + code.substring(iEnd + 1);

String output = getMethodOutputChangedCodeWithInput(code, className, "main", input1.replaceAll(" ", "\n"));

String[] lines = output.split("\n");

for (String line : lines) {
            if(line.matches(".*\\d"))
                actual += line + "\n";
        }

}
        String values = actual.replaceAll("\\D", "");
       
        boolean passed = values.equals("4222");

getResults(expected, actual, "Correct output for test case 1", passed);
        assertTrue(passed);
    }

@Test
        public void test10() {
            String className = "StudentsTest2";
            String code = getCode();

String actual = "";
            String expected = "Number of ninth graders: 3\n" +
                "Number of tenth graders: 4\n" +
                "Number of eleventh graders: 1\n" +
                "Number of twelfth graders: 2";

if(code.contains("new ArrayList")) {

code = code.replace("Main", className).replace("public class", "class");
            int iFor = code.indexOf("for(int");

if (iFor == -1) iFor = code.indexOf("for (int");
               
            int iEnd = code.indexOf("}", iFor) + 1;

int inAL = code.indexOf("<Student>");
            int inEq = code.indexOf("=", inAL);
            String name = code.substring(inAL, inEq).split(" ")[1].trim();
            //System.out.println(name);

String newCode = "\n\ns.get(0).setGradeLevel(10);\n  s.get(1).setGradeLevel(11);\n  s.get(2).setGradeLevel(9);\n  s.get(3).setGradeLevel(9);\n  s.get(4).setGradeLevel(10);\n  s.get(5).setGradeLevel(10);\n  s.get(6).setGradeLevel(12);\n  s.get(7).setGradeLevel(9);\n  s.get(8).setGradeLevel(12);\n  s.get(9).setGradeLevel(10);";
            newCode = newCode.replaceAll("s.get", name + ".get");

code = code.substring(0, iEnd) + newCode + code.substring(iEnd + 1);
            //System.out.println(code);

String output = getMethodOutputChangedCodeWithInput(code, className, "main", input1.replaceAll(" ", "\n"));

String[] lines = output.split("\n");
           
            for (String line : lines) {
                if(line.matches(".*\\d"))
                    actual += line + "\n";
            }

}

String values = actual.replaceAll("\\D", "");

boolean passed = values.equals("3412");

getResults(expected, actual, "Correct output for test case 2", passed);
            assertTrue(passed);
        }

private String getMethodCode(String code, String name) {
        String searchStr = code;
        int start = searchStr.indexOf(name);
        searchStr = searchStr.substring(start);

int level = 0;

for (int i = 0; i < searchStr.length(); i++) {
            if (searchStr.substring(i,i+1).equals("{")) {
                level++;
            } else if (searchStr.substring(i,i+1).equals("}")) {
                level--;

if (level == 0) {
                    //System.out.println(searchStr.substring(0, i+1).trim());
                    return searchStr.substring(0, i+1).trim();
                }
            }
        }

return searchStr.trim();
    }

private boolean stringMatch(String str1, String str2) {
        str1 = str1.replaceAll(" ", "");
        str2 = str2.replaceAll(" ", "");

return str1.contains(str2);
    }

private String replaceTags(String str) {
        return str.replaceAll(">","&gt;").replaceAll("<","&lt;");
    }
}

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