diff --git a/test/420-const-class/src/Main.java b/test/420-const-class/src/Main.java
index 44a7436..90ccf3a 100644
--- a/test/420-const-class/src/Main.java
+++ b/test/420-const-class/src/Main.java
@@ -53,15 +53,15 @@
     $opt$LoadAndClinitCheck();
   }
 
-  public static Class $opt$LoadThisClass() {
+  public static Class<?> $opt$LoadThisClass() {
     return Main.class;
   }
 
-  public static Class $opt$LoadOtherClass() {
+  public static Class<?> $opt$LoadOtherClass() {
     return Other.class;
   }
 
-  public static Class $opt$LoadSystemClass() {
+  public static Class<?> $opt$LoadSystemClass() {
     return System.class;
   }