Setup RingtoneService

app/src/main/java/com/philliphsu/clock2/util/Preconditions.java

@@ -0,0 +1,14 @@
+package com.philliphsu.clock2.util;
+
+/**
+ * Created by Phillip Hsu on 5/28/2016.
+ */
+public final class Preconditions {
+    private Preconditions() {}
+
+    public static <T> T checkNotNull(T obj) {
+        if (null == obj)
+            throw new NullPointerException();
+        return obj;
+    }
+}