Only generate @Extension once

README.md

@@ -29,6 +29,7 @@ Use `@GPrefer` to choose one construction method if multiple are available
 - Optional, strict no-reflection enforcement via `-AgsonCompileNoReflect`
 - Comments via `@GComment`
 - Several utility methods in the generated class for reading from/writing to various sources
+- Support for generating extension methods if manifold is present
 
 ## TODO
 - Support for nested types from libraries

gson-compile-processor/src/main/java/io/gitlab/jfronny/gson/compile/processor/GsonCompileProcessor.java

@@ -123,10 +123,10 @@ public class GsonCompileProcessor extends AbstractProcessor2 {
                     TypeSpec.Builder builder = find(known, current);
                     if (builder == null) {
                         builder = TypeSpec.classBuilder(s).addModifiers(Modifier.PUBLIC);
+                        if (current.size() == 1 && hasManifold) builder.addAnnotation(Cl.MANIFOLD_EXTENSION);
                         known.put(List.copyOf(current), builder);
                     }
                     if (current.size() > 1) builder.addModifiers(Modifier.STATIC);
-                    else if (hasManifold) builder.addAnnotation(Cl.MANIFOLD_EXTENSION);
                 }
             }
             // Add to parent class