package graphql.language;

import graphql.Internal;

import java.util.List;

import java.util.Map;

import java.util.function.BinaryOperator;

import java.util.function.Function;

import java.util.stream.Collectors;

import static java.util.function.Function.identity;

/**

* Helper class for working with {@link Node}s

*/

@Internal

public class NodeUtil {

public static Map<String, Directive> directivesByName(List<Directive> directives) {

return getByName(directives, Directive::getName);

}

public static Map<String, Argument> argumentsByName(List<Argument> arguments) {

return getByName(arguments, Argument::getName);

}

private static <T> Map<String, T> getByName(List<T> namedObjects, Function<T, String> nameFn) {

return namedObjects.stream().collect(Collectors.toMap(

nameFn,

identity(),

mergeFirst())

);

}

private static <T> BinaryOperator<T> mergeFirst() {

return (o1, o2) -> o1;

}

}