diff --git a/tools/aconfig/aconfig/src/codegen/java.rs b/tools/aconfig/aconfig/src/codegen/java.rs
index 84a17e5..2cb98ed 100644
--- a/tools/aconfig/aconfig/src/codegen/java.rs
+++ b/tools/aconfig/aconfig/src/codegen/java.rs
@@ -531,6 +531,9 @@
                     disabledRwInOtherNamespace = reader.getBooleanFlagValue(3);
                 } catch (Exception e) {
                     // pass
+                } catch (NoClassDefFoundError e) {
+                    // for mainline module running on older devices.
+                    // This should be replaces to version check, after the version bump.
                 }
                 isCached = true;
             }
diff --git a/tools/aconfig/aconfig/templates/FeatureFlagsImpl.java.template b/tools/aconfig/aconfig/templates/FeatureFlagsImpl.java.template
index 0352452..98add32 100644
--- a/tools/aconfig/aconfig/templates/FeatureFlagsImpl.java.template
+++ b/tools/aconfig/aconfig/templates/FeatureFlagsImpl.java.template
@@ -29,6 +29,9 @@
             {{ -endfor }}
         } catch (Exception e) \{
             // pass
+        } catch (NoClassDefFoundError e) \{
+            // for mainline module running on older devices.
+            // This should be replaces to version check, after the version bump.
         }
         isCached = true;
     }