diff --git a/app/src/main/java/com/philliphsu/clock/Alarm.java b/app/src/main/java/com/philliphsu/clock/Alarm.java
index 56438d1..39b10f1 100644
--- a/app/src/main/java/com/philliphsu/clock/Alarm.java
+++ b/app/src/main/java/com/philliphsu/clock/Alarm.java
@@ -1,7 +1,5 @@
 package com.philliphsu.clock;
 
-import android.support.annotation.NonNull;
-
 import com.google.auto.value.AutoValue;
 
 import java.util.Calendar;
@@ -153,8 +151,8 @@ public abstract class Alarm {
         }
         */
         public abstract Builder recurringDays(boolean[] recurringDays);
-        public abstract Builder label(@NonNull String label);
-        public abstract Builder ringtone(@NonNull String ringtone);
+        public abstract Builder label(String label);
+        public abstract Builder ringtone(String ringtone);
         public abstract Builder vibrates(boolean vibrates);
         // To enforce preconditions, split the build method into two. autoBuild() is hidden from
         // callers and is generated. You implement the public build(), which calls the generated
@@ -178,8 +176,4 @@ public abstract class Alarm {
         if (day < SUNDAY || day > SATURDAY)
             throw new IllegalArgumentException("Invalid day " + day);
     }
-
-    public static void main(String[] args) {
-
-    }
 }
diff --git a/app/src/test/java/com/philliphsu/clock/AlarmTest.java b/app/src/test/java/com/philliphsu/clock/AlarmTest.java
index 80438c7..187632e 100644
--- a/app/src/test/java/com/philliphsu/clock/AlarmTest.java
+++ b/app/src/test/java/com/philliphsu/clock/AlarmTest.java
@@ -5,14 +5,11 @@ import org.junit.Test;
 import java.util.Calendar;
 import java.util.GregorianCalendar;
 
-import static java.util.Calendar.DAY_OF_MONTH;
-import static java.util.Calendar.DAY_OF_WEEK;
+import static java.lang.System.out;
 import static java.util.Calendar.HOUR_OF_DAY;
 import static java.util.Calendar.MILLISECOND;
 import static java.util.Calendar.MINUTE;
-import static java.util.Calendar.MONTH;
 import static java.util.Calendar.SECOND;
-import static java.util.Calendar.YEAR;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
@@ -23,7 +20,7 @@ import static org.junit.Assert.assertTrue;
 public class AlarmTest {
 
     @Test
-    public void testRecurrence() {
+    public void setRecurringDays_VerifyElementsSetCorrectly() {
         Alarm alarm = Alarm.builder().build();
         
         // Some true, some false
@@ -39,6 +36,13 @@ public class AlarmTest {
             assertFalse(alarm.isRecurring(i));
         }
         assertFalse(alarm.hasRecurrence());
+
+        try {
+            alarm.setRecurring(7, true);
+            alarm.setRecurring(-3, false);
+        } catch (IllegalArgumentException e) {
+            out.println("Caught setting recurrence for invalid days");
+        }
     }
 
     @Test
@@ -46,7 +50,7 @@ public class AlarmTest {
         GregorianCalendar now = new GregorianCalendar();
         for (int h = 0; h < 24; h++) {
             for (int m = 0; m < 60; m++) {
-                System.out.println(String.format("Testing %02d:%02d", h, m));
+                out.println(String.format("Testing %02d:%02d", h, m));
                 int hC = now.get(HOUR_OF_DAY); // Current hour
                 int mC = now.get(MINUTE);      // Current minute
                 Alarm a = Alarm.builder().hour(h).minutes(m).build();
@@ -79,36 +83,27 @@ public class AlarmTest {
 
     @Test
     public void snoozeAlarm_AssertEquals_SnoozingUntilMillis_CorrespondsToWallClock() {
-        // Expected
         Calendar cal = new GregorianCalendar();
         cal.add(MINUTE, 10);
-        // Actual
-        Calendar snoozeCal = new GregorianCalendar();
         Alarm alarm = Alarm.builder().build();
         alarm.snooze(10);
-        snoozeCal.setTimeInMillis(alarm.snoozingUntil());
-
-        assertEquals(cal.get(YEAR), snoozeCal.get(YEAR));
-        assertEquals(cal.get(MONTH), snoozeCal.get(MONTH));
-        assertEquals(cal.get(DAY_OF_MONTH), snoozeCal.get(DAY_OF_MONTH));
-        assertEquals(cal.get(DAY_OF_WEEK), snoozeCal.get(DAY_OF_WEEK));
-        assertEquals(cal.get(HOUR_OF_DAY), snoozeCal.get(HOUR_OF_DAY));
-        assertEquals(cal.get(MINUTE), snoozeCal.get(MINUTE));
-        assertEquals(cal.get(SECOND), snoozeCal.get(SECOND));
-        // Milliseconds not required to be equal, because they will always
-        // have some difference
+        // Unlike ring times, the snoozingUntilMillis has seconds and millis components.
+        // Due to the overhead of computation, the two time values will inherently have some
+        // millis difference. However, if the difference is meaningfully small enough, then
+        // for all practical purposes, we can consider them equal.
+        assertTrue(Math.abs(alarm.snoozingUntil() - cal.getTimeInMillis()) <= 10);
     }
 
     @Test
     public void snoozeAlarm_IsSnoozed_ReturnsTrue_ForAllMillisUpToButExcluding_SnoozingUntilMillis() {
         Alarm alarm = Alarm.builder().build();
         alarm.snooze(1);
-        // If all iterations leading up to 20ms before the target time evaluate to true,
-        // that is good enough and we don't really care about the last 20ms.
-        while (alarm.snoozingUntil() - System.currentTimeMillis() > 20) {
+        // Stop 10ms early so System.currentTimeMillis() doesn't exceed the target time in the middle
+        // of an iteration.
+        while (System.currentTimeMillis() < alarm.snoozingUntil() - 10) {
             assertTrue(alarm.isSnoozed());
         }
-        // Wait long enough so the target time passes.
+        // Wait just in case so the target time passes.
         try {
             Thread.sleep(20);
         } catch (InterruptedException e) {