Project finished

src/RomanNumerals.java

@@ -1,8 +1,109 @@
+import java.util.*;
 
 public class RomanNumerals {
+
+	private TreeMap<String, Integer> numbers;
+
+	public RomanNumerals(){
+		numbers = new TreeMap<String, Integer>();
+		numbers.put("I", 1);
+		numbers.put("V", 5);
+		numbers.put("X", 10);
+		numbers.put("L", 50);
+		numbers.put("C", 100);
+		numbers.put("D", 500);
+		numbers.put("M", 1000);
+	}
+
 	public int convertToInteger(String romanNum) {
-		// To be Implemented
+
+		return convertMultiple(romanNum);
+
+	}
+	private int convertMultiple(String romanNum){
+		String[] n = romanNum.split("");
+		if(checkThreeTimes(n) && substractOkay(n)){
+			return count(n);
+		}
 		return 0;
 
 	}
+	//count for checking the total
+	private int count(String[] n){
+		int c = numbers.get(n[n.length - 1]);
+		String prev = n[n.length - 1];
+		for(int i = n.length -2; i >= 0; i--){
+			if(numbers.get(prev) > numbers.get(n[i])){
+				c -= numbers.get(n[i]);
+			}
+			else{
+				c += numbers.get(n[i]);
+			}
+			prev = n[i];
+		}
+		return c;
+	}
+	private boolean substractOkay(String[] n){
+		String prev = n[n.length - 1];
+		int times = 0;
+		for(int i = n.length - 2; i >= 0; i--){
+			if(prev.equals("M") || prev.equals("D")){
+				if(!n[i].equals("C")){
+					return false;
+				}
+				else{
+					times++;
+				}
+			}
+			if(prev.equals("C") || prev.equals("L")){
+				if(!n[i].equals("X")){
+					return false;
+				}
+				else{
+					times++;
+				}
+			}
+			if(prev.equals("X") || prev.equals("V")){
+				if(!n[i].equals("I")){
+					return false;
+				}
+				else{
+					times++;
+				}
+			}
+			if(n[i].equals("V") || n[i].equals("L") || n[i].equals("D")){
+				if(numbers.get(n[i]) < numbers.get(prev)){
+					return false;
+				}
+			}
+			if(!n[i].equals("I") || !n[i].equals("X") || !n[i].equals("C")){
+				times = 0;
+			}
+			if(times > 1){
+				return false;
+			}
+			prev = n[i];
+		}
+		return true;
+	}
+	private boolean checkThreeTimes(String[] n){
+
+		String prev = n[n.length - 1];
+		int times = 0;
+		for(int i = n.length - 2; i >= 0; i--){
+			if(prev.equals(n[i])){
+				times++;
+			}
+			if(times > 2){
+				return false;
+			}
+			if(!prev.equals(n[i])){
+				times = 0;
+			}
+			prev = n[i];
+		}
+		return true;
+
+	}
+
 }

tests/TestRomanNumerals.java

@@ -4,9 +4,69 @@
 
 public class TestRomanNumerals {
 
+	RomanNumerals num = new RomanNumerals();
 	@Test
-	public void test() {
-		fail("Not yet implemented");
+	public void test_ConvertToInteger() {
+
+		int arabic = num.convertToInteger("I");
+		assertEquals("Number is not one", 1, arabic);
 	}
+	@Test
+	public void test_ConvertToIntegerThree(){
+
+		int arabic = num.convertToInteger("III");
+		assertEquals("Number is not three", 3, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerFive(){
+
+		int arabic = num.convertToInteger("V");
+		assertEquals("Number is not five", 5, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerTen(){
+
+		int arabic = num.convertToInteger("X");
+		assertEquals("Number is not ten", 10, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerFifty(){
+
+		int arabic = num.convertToInteger("L");
+		assertEquals("Number is not fifty", 50, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerHundred(){
+
+		int arabic = num.convertToInteger("C");
+		assertEquals("Number is not hundred", 100, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerFour(){
+
+		int arabic = num.convertToInteger("IV");
+		assertEquals("Number is not four", 4, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerSeve(){
+		int arabic = num.convertToInteger("VII");
+		assertEquals("Number is not seven", 7, arabic);
+	}
+	@Test
+	public void test_ConvertToIntegerNine(){
+		int arabic = num.convertToInteger("IX");
+		assertEquals("Number is not nine", 9, arabic);
+	}
+	@Test
+	public void test_NotRepeated(){
+		int arabic = num.convertToInteger("VV");
+		assertEquals("Number cannot be repeated", 0, arabic);
+	}
+	@Test
+	public void test_Substraction(){
+		int arabic = num.convertToInteger("XXC");
+		assertEquals("Number is substracted even though not possible", 0, arabic);
+	}
+
 
 }