Search code examples
javajavapoet

How to generate Class parameter with javapoet?


I need generate next java.class parameter for enum class:

    public enum ServiceType {

        //....
        private final Class<?> mClass; //<<how?

        ServiceType(final Class<?> clazz) {
            this.mClass = clazz;
        }

        public Class<?> getCurrentClass() {
            return mClass;
        }
        //...
    }

And i don't found - how make this field.

My code for generation this class:

        File path = new File(Path.ROOT + ENUM_PATH);

        TypeSpec.Builder servicesEnumBuilder = TypeSpec.enumBuilder(ENUM_CLASS_NAME)
                .addModifiers(Modifier.PUBLIC);

        for (Map.Entry<String, String> entry: foundedServices.entrySet()) {
            servicesEnumBuilder.addEnumConstant(
                    entry.getKey().toUpperCase() + ENUM_SUFFIX,
                    TypeSpec.anonymousClassBuilder("$T", ClassName.get(entry.getValue() , entry.getKey())).build());
        }

        servicesEnumBuilder.addField(); //<< how add this field: private final Class<?> mClass;

Solution

  • You can check this answer

    Applied to your case it would be something like this:

        TypeName wildcard = WildcardTypeName.subtypeOf(Object.class);
        TypeName classOfAny = ParameterizedTypeName.get(
                ClassName.get(Class.class), wildcard);
        FieldSpec field = FieldSpec.builder(classOfAny, "mClass")  // You may consider using a constant here
                .addModifiers(Modifier.PRIVATE, Modifier.FINAL)
                .build();
    
        servicesEnumBuilder.addField(field);