Add requireNonNull test

Author: tinylambda

src/main/java/keep/javautil/JavaUtilRequireNonNull.java

@@ -0,0 +1,13 @@
+package keep.javautil;
+
+import static java.util.Objects.requireNonNull;
+
+
+public class JavaUtilRequireNonNull {
+    public static void main(String[] args) {
+        String value = null;
+        // Checks that the specified object reference is not {@code null} and
+        // throws a customized {@link NullPointerException} if it is.
+        requireNonNull(value, "value is null");
+    }
+}