code: private TypeSpec generateBuilder( RestService restService ) {
  
          TypeSpec.Builder typeBuilder = TypeSpec.classBuilder( restService.getBuilderSimpleClassName() )
                  .addModifiers( Modifier.PUBLIC, Modifier.FINAL )
                  .addJavadoc( "Generated REST service builder for {@link $L}.\n", restService.getTypeElement().getQualifiedName() )
                  .addMethod( MethodSpec.constructorBuilder().addModifiers( Modifier.PRIVATE ).build() );
  
          Map<TypeMirror, MethodSpec> mapperGetters = buildMappers( typeBuilder, restService );
  
          for ( RestServiceMethod method : restService.getMethods() ) {
              buildMethod( typeBuilder, mapperGetters, method );
          }
  
          return typeBuilder.build();
      }
docs: Generate the rest service builder
  
  @param restService The rest service