code: public void resolveBuilderGen() {
          if (getBean().isMutable()) {
              if (!getBean().isBuilderScopeVisible() && !getBean().isBeanStyleLightOrMinimal()) {
                  return;  // no builder
              }
          }
          if (isDerived()) {
              builderGen = BuilderGen.NoBuilderGen.INSTANCE;
          } else {
              BuilderGen builder = config.getBuilderGenerators().get(getFieldTypeRaw());
              if (builder != null) {
                  builderGen = builder;
              } else {
                  builderGen = new BuilderGen.SimpleBuilderGen();
              }
          }
      }
docs: Resolves the copy generator.