Assignment finished

src/CalculatorUtils.java

@@ -0,0 +1,27 @@
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+// Refactor: Extract method
+
+public class CalculatorUtils {
+
+	// Beautify this class and handle errors
+	public static String[] convertToNumberStringArray(String numbers) {
+
+		String[] arrayOfNumbers = numbers.split("\\s*,\\s*"); 
+
+		return arrayOfNumbers;
+	}
+
+	public static String[] removeEmptyStrings(String[] numbersArray) {
+
+		List<String> myList = new ArrayList<String>(Arrays.asList(numbersArray));
+		myList.remove("");
+
+		String[] myStrArray = myList.toArray(new String[0]);
+
+		return myStrArray;
+	}
+
+}

src/NumberObject.java

@@ -0,0 +1,59 @@
+
+// Refactor: Introduce Parameter Object
+public class NumberObject {
+	private String numbersStr;
+	private int value;
+	private String[] numbersArray;
+
+	public NumberObject(String numbersStr) {
+		this.numbersStr = numbersStr;
+		this.value = 0;
+		this.numbersArray = null;
+	} 
+
+	public String getNumbersStr() {
+		return this.numbersStr;
+	}
+
+	public String[] getNumbersArray() {
+		return this.numbersArray;
+	}
+
+	public void setNumbersArray(String[] numbersArray) {
+		this.numbersArray = numbersArray;
+	}
+
+	public int getValue() {
+		return this.value;
+	}
+
+	public void setValue(int value) {
+		this.value = value;
+	}
+
+	// Refactor: BAD SMELL, JDEADORANT MOVED
+	public boolean isNumberStrValid() {
+		return getNumbersStr() != null && getNumbersStr() != "";
+	}
+
+	// Refactor: Extract method
+	// Refactor: BAD SMELL, JDEADORANT MOVED
+	public int calculate() throws StringCalculatorException {
+		try {
+			// Remove the "" from the list
+			setNumbersArray(CalculatorUtils.convertToNumberStringArray(getNumbersStr()));
+			setNumbersArray(CalculatorUtils.removeEmptyStrings(getNumbersArray()));
+
+			int val = 0;
+			for (String numberString : getNumbersArray()) {
+				val += Integer.parseInt(numberString);
+			}
+			setValue(val);
+		}
+		catch (IllegalArgumentException e) {
+			throw new StringCalculatorException();
+		}
+		return getValue();
+	}
+
+}

src/StringCalculator.java

@@ -1,9 +1,26 @@
+/*
+Implement a simple String calculator with a method int Add(string numbers)
+1. The method can take 0, 1 or 2 numbers, and will return their sum (for an empty string it will
+return 0) for example �� or �1� or �1,2�
+2. Add method to handle an unknown amount of numbers
+3. Add method to handle new lines between numbers (instead of commas).
+1. the following input is ok: �1\n2,3� (will equal 6)
+2. the following input is NOT ok: �1,\n�
+4. Calling Add with a negative numbers or invalid input (not numbers) will throw an
+StringCalculatorException
+*/
 
 public class StringCalculator {
-	public int add(String numbersStr) {
-		// Returns the sum of the numbers given in numbersStr
+	// Main function
+	public int add(String numbersStr) throws StringCalculatorException {
 
-		// not yet implemented
-		return 0;
+		NumberObject numberObject = new NumberObject(numbersStr);
+
+		int val = 0;
+		if (numberObject.isNumberStrValid()) {			
+			val = numberObject.calculate();
+		}
+		return val;
 	}
+
 }

tests/StringCalculatorTest.java

@@ -3,10 +3,122 @@
 import org.junit.Test;
 
 public class StringCalculatorTest {
+
+	@Test
+	public void test_add_valid() throws StringCalculatorException{
+		// Arrange
+		StringCalculator calculator = new StringCalculator();
+		String testString = "11, 2, , 3, 31";
+
+		// Act
+		int returnedValue = calculator.add(testString);
+
+		// Assert
+		assertEquals(47, returnedValue);
+	}
 
 	@Test
-	public void test() {
-		fail("Not yet implemented");
+	public void test_add_with_zero() throws StringCalculatorException{
+		// Arrange			
+		StringCalculator calculator = new StringCalculator();
+		String testString = "0, 2, , 3";
+
+		// Act
+		int returnedValue = calculator.add(testString);
+
+		// Assert
+		assertEquals(5, returnedValue);
+	}
+
+	@Test
+	public void test_add_zero() throws StringCalculatorException{
+		// Arrange	
+		StringCalculator calculator = new StringCalculator();
+		String testString = "0, ";
+
+		// Act
+		int returnedValue = calculator.add(testString);
+
+		// Assert
+		assertEquals(0, returnedValue);
 	}
 
+	@Test  (expected = StringCalculatorException.class)
+	public void test_add_empty() throws StringCalculatorException{
+		// Arrange	
+		StringCalculator calculator = new StringCalculator();
+		String testString = " ";
+
+		// Act
+		calculator.add(testString);
+	}
+
+	@Test
+	public void test_add_null() throws StringCalculatorException{
+		// Arrange	
+		StringCalculator calculator = new StringCalculator();
+
+		// Act
+		int returnedValue = calculator.add(null);
+
+		// Assert
+		assertEquals(0, returnedValue);
+	}
+
+	@Test
+	public void test_removeEmptyString() {
+		// Arrange
+		String[] testArray = {"21", "1", "", "15"};
+
+		// Act
+		String[] returnedArray = CalculatorUtils.removeEmptyStrings(testArray);
+
+		// Assert
+		String[] expectedArray = {"21", "1", "15"};
+		assertArrayEquals(returnedArray, expectedArray);
+	}
+
+	@Test
+	public void test_convertToArray() {
+		// Arrange
+		String testString = "1,15\n , ,3";
+
+		// Act
+		String[] returnedArray = CalculatorUtils.convertToNumberStringArray(testString);
+
+		// Assert
+		String[] expectedArray = {"1", "15", "", "3"};
+		assertArrayEquals(returnedArray, expectedArray);
+	}
+
+
+	@Test 
+	public void test_add_plainString() throws StringCalculatorException{
+		// Arrange
+		StringCalculator calculator = new StringCalculator();
+		String testString = "1,40\n, 3";
+
+		// Act
+		int returnedValue = calculator.add(testString);
+
+		// Assert
+		int expected = 44;
+		assertEquals(expected, returnedValue);
+
+	}
+
+	@Test 
+	public void test_add_plainStringWithEmpty() throws StringCalculatorException{
+		// Arrange
+		StringCalculator calculator = new StringCalculator();
+		String testString = " , 2\n , , , , ";
+
+		// Act
+		int returnedValue = calculator.add(testString);
+
+		// Assert
+		int expected = 2;
+		assertEquals(expected, returnedValue);
+
+	}
 }