add random policy test

src/test/java/DummyAction.java

@@ -0,0 +1,6 @@
+public enum DummyAction {
+    UP,
+    DOWN,
+    RIGHT,
+    LEFT
+}

src/test/java/PolicyTest.java

@@ -0,0 +1,50 @@
+import core.RNG;
+import core.policy.RandomPolicy;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class PolicyTest {
+
+    private Map<DummyAction, Double> createActionValueMap(){
+        Map<DummyAction, Double> actionValues = new HashMap<>();
+        actionValues.put(DummyAction.UP, 1d);
+        actionValues.put(DummyAction.DOWN, 2d);
+        actionValues.put(DummyAction.LEFT, 3d);
+        actionValues.put(DummyAction.RIGHT, 4d);
+
+        return actionValues;
+    }
+
+    /**
+     * Test if the random policy generates true random results
+     * based upon the static RNG class.
+     */
+    @Test
+    public void RandomPolicyTest(){
+        RandomPolicy<DummyAction> randomPolicy =  new RandomPolicy<>();
+        Map<DummyAction, Double> dummyActionValues = createActionValueMap();
+
+        // dummy action space to choose an action from
+        List<DummyAction> actionList = new ArrayList<>(dummyActionValues.keySet());
+        // list of 100 random selected actions in a row
+        List<DummyAction> chosenActions = new ArrayList<>();
+
+        // randomly selecting an action based upon an index generated from RNG class
+        RNG.setSeed(123);
+        for(int i = 0; i < 100; ++i){
+            int randomPos = RNG.getRandom().nextInt(actionList.size());
+            chosenActions.add(actionList.get(randomPos));
+        }
+
+        // check if all randomly chosen action in the implementation rely
+        // on RNG static class
+        RNG.setSeed(123);
+        for(DummyAction action : chosenActions){
+            assert (action == randomPolicy.chooseAction(dummyActionValues));
+        }
+    }
+}