add junit test for roll service

build.gradle

@@ -14,4 +14,5 @@ repositories {
 
 dependencies {
     testCompile 'junit:junit:4.12'
+    testCompile 'org.hamcrest:hamcrest-all:1.3'
 }

src/test/java/com/pickominio/service/RollTest.java

@@ -0,0 +1,39 @@
+package com.pickominio.service;
+
+import com.pickominio.model.ActiveDiceSet;
+import com.pickominio.model.Dice;
+import com.pickominio.model.DiceSet;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.stream.Stream;
+
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.greaterThanOrEqualTo;
+import static org.hamcrest.Matchers.lessThanOrEqualTo;
+import static org.junit.Assert.*;
+
+public class RollTest {
+    private DiceSet diceSet;
+    private Roll roll;
+
+    @Before
+    public void setUp() throws Exception {
+        diceSet = ActiveDiceSet.buildNewSet();
+        roll = new Roll();
+    }
+
+    @Test
+    public void diceSet() {
+        roll.diceSet(diceSet);
+        int[] values = Stream.of(diceSet.toString().split(" "))
+                .mapToInt(value -> Integer.parseInt(value))
+                .toArray();
+        for (int diceValue : values) {
+            assertThat(
+                diceValue,
+                allOf(greaterThanOrEqualTo(Dice.MIN_DICE_VALUE), lessThanOrEqualTo(Dice.MAX_DICE_VALUE))
+            );
+        }
+    }
+}